Kiwi Ears KE4

NOTES:

Kiwi Ears is not stranger to most. It is a storied brand with a number of previous releases including the well received Orchestra & Quintet. I have owned the Cadenza and Quintet previously with the Quintet being an impressive standout by any measure.

The KE4 is their latest release and does distinguish itself with a tuning that follows the “Meta” standard. In a nutshell Meta tuning is defined as “IEMs measured with midrange and treble adherent to a population average DF HRTF when measured on a Type 4.3 system like the B&K 5128." This a departure from the typical Harman signature resulting in my opinion a more natural presentation.

Now for a little rant on “tuning preferences”. For the most part having a preference to a particular tuning just indicates a liking for a set of sonic colorations. When some lament that the Meta tuning sounds boring or lifeless what can be gleaned from this reaction is they could be talking about the lack of these colorations. After listening to much well recorded acoustic music I can honestly say that the KE4 with it’s Meta tuning gets it right the majority of the time. It is far from boring or limited in frequency range as some have reported. Instead, it is a clearer window into what the music really sounds like than most Harman sets I have recently heard. It all comes down to perspective and the realization that music is indeed a subjective thing.

The KE4’s drive compliment includes “2x 10mm Dynamic Driver (2DD) isobaric sub-woofer system combined with 2 Balanced Armature (2BA) full-range (RAD-32257) and tweeter, Knowles (33518)” Terms “Isobaric” may trigger some folks questioning weather it is a true implementation of the tech or just a marketing exaggeration as seen all to often. In the end, the drivers of the KE4 are obviously implemented in a very competent way resulting in great sound.

The KE4 was fairly easy to drive but does benefit, in particular in the bass, from a more competent source.

Read on to find out more.

SPECS:

Product: Kiwi Ears KE4

Format: Hybrid in-ear type

Woofer: 2x 10mm Dynamic Driver

Mid-High Frequency: RAD-33581

Tweeter: Knowles 33518

Housing Material: Resin

Sound pressure level: 102dB

3-way Crossover

Impedance: 28Ω

BUILD FIT & QUALITY:

The Kiwi Ears KE4 uses a similar resin shell as that of the Quintet but with a shiny faceplate with company branding. The shells are beautifully made, smooth with a flawless transition from shell to backplate. There is a visible port for venting on rear of the shell.

The KE4 is on the larger side of medium sized with some front to back bulk. They did fit comfortably and firmly in my ears with the shape allowing the moderately protruding nozzle good positioning in my ear canal. There is a pack of 2 pairs of nozzle filters also included.

The included accessories while sparse are of high quality as well. The cable provided was a 3.5mm but was swapped out to a 4.4mm SPC for the duration of the testing.











SOUND:

BASS:

The Kiwi Ears KE4 has a bass that goes deep favoring mid-bass over sub-bass. Sub-bass is absolutely present, but the mid-bass is the star here.

I hit the ground running with “Angel” by Massive Attack. The KE4 offers up a bass that goes deep with good texturing. The texture of the driving bassline in this track is lost on some earphones. Not so with the KE4 where it is quite audible.

“Stella” by A Guy Called Gerald was next and I did enjoy how the KE4 relayed the thick richness of the bass line and kick drum with great control. The bass in this track never overshadowed and other elements.

Listening to acoustic double bass on “No Worries” by the Robert Glasper Trio echoed the previous observations. The bass had a thick roundness without sacrificing much of the detail and speed. “Barley” by Lizz Wright showed the same characteristics of a thick rounded bass with good texturing and speed.

MIDRANGE:

Let me get this out of the way. The Kiwi ears KE4 has a midrange that can be described in one word, “Natural”. It is an open sounding and detailed midrange with a good mix of macro and micro details present, favouring macro somewhat.

Lizz Wright’s husky female vocals on “Barley” had great clarity and warmth that was organic. Denis Brown’s vocals on “Here I Come” followed suit sounding again warm and natural.

Moving over to “He’s a Carioca” by Eden Atwood, the KE4’s playback was very pleasing. I’m going be repetitive, but organic and natural is honestly the best way to describe what was heard. No undue emphasis, in particular in the upper midrange was heard.

The KE4 upper midrange is where there may be differing opinions and this is where the Meta tuning debate comes in. The upper mids or pinna gain area is not as pronounced as on more than just a few Harman tuned iems I have heard. It is controlled which some may feel lacks engagement. I disagree with this sentiment. I find the Meta approach less colored and more natural which to me is more exciting from a sonic standpoint.
The winner here is timbre which the KE4 presents well. Separation and dynamics were done well adding to the organic nature of the KE4’s playback. The KE4 with all of it’s driver tech also came off as coherent in its presentation. There was no clear separation of frequency ranges and all flows together smoothly.

TREBLE:

The Kiwi Ears KE4 has a natural sounding treble with good extension and little to no fatiguing qualities. Sparkle and air are ample and not overdone to sound more “Exiting”. There is no lack of energy here, just the right amount of energy to give an accurate portrail of what is in the track.

Listening to “Vanston Place 12am” by Ronny Jordan one could hear all those elements clearly with all the above-mentioned characteristics present.

The intricate cymbal work on “No Worries” by the Robert Glasper Trios was rendered very nicely with great detail.

The treble of the KE4 is done very well. The only negative I could find is that on some tracks, with middling recording quality, the treble of the KE4 did at times have a slight hardness to it. This was never an issue with well recorded music and as such I would deem the KE4 as being moderately tolerant of poor recordings.



IMAGING AND SOUNDSTAGE:

The Kiwi ears KE4 offers up a pleasantly engaging soundstage with good width and height, and to a lesser but still pleasing extent depth. The Layering ability of the KE4 really opens things up here and instrument placement is sharp and steady. The KE4 can at times though struggle on very complex tracks, but more so at higher than normal volume levels.






CONCLUSION:

The Kiwi Ears KE4 is an iem that gets my firm recommendation, but with caveats. This is not a “Me Too” tuned iem. It is for those who value a balanced and nuanced presentation and can differentiate the more “Excitingly coloured” tunings from the level of “Natural Organic Excitement” that it offers. For my ears, Natural and Organic always win.

I for one came away impressed with the KE4. If you are someone who craves this type of sonic presentation, it should be high on your shortlist.

WATCH FULL REVIEW HERE:​

PROS:​

• Follows the JM-1 Target
• Very well-balanced and versatile on different genres
• Safe and inoffensive tuning
• Rich and warm tone
• Superb extension on both ends
• Good coherency with minimal metallic timbre
• Good fit and accessories

CONS:​

• Might be too safe for some
• Not the most technical sounding IEM for the price
• Bass can sound too smooth
• Can sound too warm
• Treble energy can be lacking

WHO THIS SET IS FOR:​

• Measurebators
• People who like a safe and versatile tuning
• People who want good and stable fit
• People who like a coherent and consistent sound

WHO THIS SET ISN’T FOR:​

• People who want a fun and engaging set
• People who want a tactile and nuanced low end
• People who want an open sounding midrange
• People who want a dynamic listening experience

RECOMMENDED GENRES:​

• All genres minus mezzo-soprano female vocals

SHORT REVIEW:​

Meta means optimal, and the KE4 is probably the most optimal sounding IEM. Superb tonal balance, phenomenal end to end extension and a tuning that will sound great with most genres. However, it’s biggest strength is also its biggest weakness as it lacks the excitement that I usually get from more V-Shaped sounding sets. Regardless, the KE4 and the JM-1 to an extent proves that audio has not stagnated quite yet. RECOMMENDED!

FULL REVIEW​

Meta. Mainly used in video games, now being used for headphones? What’s happening? Well, to tell a long story short that I will also tell again later in this review, the recent advancement of headphone measurements lead to the creation of update preference targets and compensation that brought about the most “scientific” way to tune headphones today.

But this only fuels the flames for the war between the “trust your ears” clan and “measurebator” clan to further discuss what it is exactly is the best way to evaluate headphones. So let me give my two cents, along with a comprehensive review of one of the better IEMs to follow the infamous JM-1 target.

DISCLAIMER: The KE4 was sent in exchange for my honest thoughts. I was not paid or compensated to say anything about the product.

ONE TIME FOR THE MEASUREBATORS, ONE TIME FOR THE FR BROS​

Normally, I talk about the history of the brand in this section. However, I want to add a bit of context to that entire intro discussion on “preference bounds” . First, let’s talk about Kiwi Ears.

This is my second rodeo with Kiwi Ears, which is also my second rodeo for their isobaric 2DD tech that they seem to enjoy doing. My first experience with them, the Kiwi Ears Quartet was less than desirable. I enjoyed how it looked, I enjoyed how it fit, I did not enjoy how it sounded. Tonal issues, coherency issues and QC issues plagued that set that lead me to give it a rather lukewarm review. I didn’t think it was unbearably bad, but it could have been better.

Well, Kiwi Ears may have just made something better with the KE4. Same isobaric configuration but a hell lot better coherency. But arguably its selling point is that it follows the infamous JM-1 target (specifically the 10db tilt version). But what the hell is the JM-1, what are preference bounds? What even are all these fancy terms? Well, let me give you a very brief explanation to all of this.

Before I continue, I would like to preface this by saying that I will be talking about some rather nerdy crap and you can completely skip this entire part if you’re not interested. However, I highly recommend you read this as it provides good context of my conclusion on the KE4 later.

Also, I will be linking a couple of articles and videos to thoroughly explain the many topics I will cover in this review as I oversimplified a lot of information for the sake of time and sanity. Check it out at the very bottom if you’re interested.

Gentlemen, A Short View Back To The Past​

The evolution of audio products have been a slow, steady but progressive path from speakers to headphones. However, headphones in particular have only had a couple of decades of thorough research done and even shorter for in-ears. Heck, the first few “good” in-ears only appeared in the later part of the 20th century and many of you have probably been born longer than the development of in-ears.

This means that the technology to properly evaluate audio gears such as headphones (I will put headphones and in-ear in the same category for redundancy’s sake) have been less than ideal. Free-field was the generally accepted measurement standard back in the day, but this proved to be problematic by a couple of people. This lead to the creation of the Diffuse Field Head Related Transfer (also known as the DF HRTF)



To explain an EXTREMELY complex term, the DF HRTF was not made as a preference target like the many targets you might find on squig.link, but is made to calibrate the measuring rig to be as accurate as possible. I HIGHLY encourage you to read up on the articles and documents explaining these concepts if you want to have a better understanding and appreciation for why headphones sound the way that they do now.



Despite the DF HRTF being basically the most accurate way to calibrate a microphone to measure as accurately as it could, the desire for a point of reference that is actually listenable was yearned for. Harman lead this development with their famous research that has now become an adjective to describe headphones. You’ll probably see a lot of reviewers and casual people call something “Harman-ish” to describe headphones and that’s for a good reason.

The measurement standard that we have been using has been based on the Harman research and 711 (which are based on the IEC60318-4 standard). While this has been the tried and tested standard for a good couple of decades now, companies like B&K have been developing more accurate simulations of the head and torso with the likes of the B&K 5128-C.

A lot of funny words and terms here, but all you need to know is that measurements are evolving and so the standards need to change.

With this change, a new way of evaluating headphones also needs to evolve. This is where the good people at Headphones.com come into play as they have been hard at work developing a pretty solid way to evaluate headphones. With the use of the Harman research and their funky B&K 5128, they’ve developed a “preference bound” that is scientifically, objectively and statistically the most “accurate” measurements that is available right now.

In-ear monitors specifically, the evolution has moved towards the JM-1. The meta tuning. This is based on the same DF HRTF used on headphones, but removing the influence of the parts of the ears that aren’t being affected by in-ears (aka that big flappy thing on the side of your heads) and compensated to the average ear.



I’m not gonna explain how the JM-1 target works or why it’s currently the most accurate target to follow the preference bound as I feel like I’m not the right person to talk about it (hint hint, links at the bottom). But the JM-1 is the closest we have to objective evaluation of neutral tuning for in-ears.

So in short, headphone measurements not good. People do research to find best way to measure headphone, people make headphone target as preference bounds, JM-1 exist for in-ears. That’s the scientific and research side of audio and they aim to make audio evaluation more accurate.

Why Do You Even Need Accurate Evaluation?​

If you’re on the clan against frequency response graphs, you might be wondering why you need this if you can just find headphones that sound good to you and know absolutely nothing about how it measures. Well, measurements exist so that we have a general understanding of what is “good”. Good is subjective, but how we can get good can be measured. That’s what the research is for in the first place and even your favorite headphones exist thanks to the evolution of objective evaluation for all audio equipment over the years.

Now that I’ve talked in depth about the whole measurement rabbit hole, let’s talk about the KE4 on its own.

UNBOXING​

To make a rather simple unboxing short, the Kiwi Ears KE4 features the usual Kiwi Ears illustration (some of the best in the market) with basic information in the back.

Here’s a full list of the accessories:

• KE4 IEMs
• 4 Core Cable
• 3 pairs of Kiwi Ears Flex Eartips
• Replacement Filters
• Carrying Case

I’m slightly disappointed with the unboxing experience of the KE4, fundamentally because of how spartan it is. While you do get Kiwi Ears Flex eartips along with a nice case, this is not a $200 unboxing experience. You ONLY get the flex eartips and the case is the same one that comes with their budget IEMs.

BUILD & FIT​

The build and fit situation of the KE4 is near identical to all their previous resin-based in-ears in terms of both the quality and the comfort. Least to say, this is probably the best large fitting in-ear that I’ve ever worn.

But let’s tackle the elephant in the room first: isobaric 2DD + 2BA hybrid with a 3-way passive crossover and 3 independent sound tubes. Once again, Kiwi Ears attempts the isobaric configuration, and this time I’d argue they succeeded.

Before I continue, I want to address that this is Kiwi Ears’ first non-music related naming. I may be incorrect and that KE4 is actually a musical notation for something (or Kiwi Ears have released a product that doesn’t have musical references) but to my knowledge, this is their first.



Externally, the aesthetics resemble the Kiwi Ears Quintet with the dark inner shell and silver faceplate. Contrary to what many people have said about the Quintet’s “boring” look, I’d argue that a silver faceplate like the one in the KE4 looks very clean and handsome. I’m not going to give it the award for the best looking IEM, but it’s simple and looks good in and out of the ear.



But arguably the issue that most people will have with the KE4 is its size. This thing is an absolute chonker and people will smaller ears will not have a great time. However, the shape is akin to their cheaper sets like the Quartet which means this thing fits in my ear like a glove. Not as well as the smaller Quartet, but certainly well enough to keep me from complaining about the fit.



The problem I had with it was the long term comfort will vary depending how you fit it in your ear. If you have the wings digging into your ear in an uncomfortable angle, it will hurt after a couple of hours. However, this can often be remedied by adjusting it before hand.



Another issue I had was the driver flex. No air pressure build up is always nice, but the driver flex may be a bit uncomfortable during first wear. I didn’t really experience any long term problems because of this, but this is something to note if you’re sensitive to the crinkling of the driver.



As for the cable, this is a very aesthetically pleasing and comfortable cable with very premium interface. I want to say this is one of, if not, my favorite 4 core cable on the thinner side, but more companies have been providing really good quality cables that I can comfortably say that the KE4’s stock cable can live amongst the greats. Maybe a modular termination would’ve made this even better, but I don’t think it needs modularity with how easy it is to drive (more on that later).

SOUND​

Sound Signature​

Here we go, the sound signature of the KE4 is what people would call nowadays, “Meta”. But what does that mean? In short, it falls within the preference bound that I mentioned early in the review based on the B&K 5128 DF HRTF and the JM-1 compensation HRTF. What this means is that it has a well balanced, well-extended and consistent sound that is made for all-rounded listening sessions. The KE4’s nuanced characteristic is its low end focus, particularly in the lower mids with a slight hump that you can hear when listening to tracks with a prominent lower to mid vocal presentation. Timbre consistency is surprisingly good, considering their last isobaric hybrid was admittedly a mess in terms of coherency. But let’s get deeper into that in a bit

Source Pairing​

The KE4 is arguably one of the most versatile sets when pairing with whatever source I plug it into. From my cheap dongles to my all-powerful SK02, the KE4 ranges from sounding good to sound great. It’s also very easy to drive as I never had any problems with volume at all, but a more powerful or cleaner source will net you better sound (duh)

Volume Levels​

I was personally expecting the KE4 to be a volume scaling monster, but that lower midrange emphasis feels so out of place the higher the volume is and forces me to go mid listening volume to keep tonal integrity and an enjoyable listening experience. It could also be attributed to the rather late eargain, but I’d argue that also plays a part with the lower midrange preventing me from going higher

Bass​

The KE4’s bass is what you might expect a “meta” bass sounds like. Clean, subbass oriented with good extension, rumble and kick without much bleed into the mids. This theoretically makes it a very ideal level of bass for whatever songs you’re listening to and to a point, I would whole heartedly agree. However, the problem with is is the smoother than tactile midbass presentation that ends up making the bass sound more linear than dynamic. It’s not the worst I’ve heard, far from it. I’d argue that the KE4 is one of the best to balance that subbass and midbass tuning. But whether it’d be the isobaric configuration just not giving enough nuance or the quality of the driver just lacking in refinement, the KE4 is closer to having a “slow” presentation than a snappy one to my ears. It’s not that slow to make it incoherent with the speed of the rest of the frequency, but it certainly affects it.

Mids​

This is the region where I’m most divisive on the KE4. While I am aware and can appreciate the “neutralness” of the midrange, I also find that the combination of a boosted lower midrange and toned down upper midrange with a late eargain makes this a very relaxed and not very engaging listening experience. On a positive not, male vocals, electric guitars and instruments that want a lot of lower midrange energy sounds perfect on this. A specific example would be the song Blue by Amateurish. Most IEMs present the overall sound in a rather thin and pale manner that sounds lifeless. The KE4 is able to give the song much needed body and lower midrange while keeping the overall tonal presentation relatively uncolored. However, the problem rises when you throw this into tracks with thicker female vocals that get drowned out by the lower midrange. Take for instance Laufey and Samara Joy. I did NOT have a satisfying listening experience with either of them on the KE4 whereas other sets, particularly leaner ones, do.

This is where the conversation of the “meta” tuning comes into play, to which I’d defend this kind of tuning for being one of the few kinds of tuning that can provide good note weight without total coloration. The aforementioned song Blue is the best example for this and older pop tracks like Earth, Wind & Fire, Fleetwood Mac and even the Japanese fusion band Casiopea sounds great on the KE4. The problem rises when you throw in vibrant upper midrange focused tracks that also have lower midrange emphasis and you start to hear why the KE4 wasn’t my cup of tea at the start. My usual test tracks included Laufey and Samara Joy and they did not sound great. But throwing this into older tracks and now we’re talking.

Treble​

Similar to the bass presentation, the treble is arguably the best thing about the KE4 in terms of neutrality. To my ears, the KE4 follows such a beautiful glide from the lower treble to the upper treble with a fatigue free but nuanced treble presentation. I honestly don’t mind that it’s not as bright or vibrant as my usual preferences as a bit of relaxation is in order if I want to keep my hearing, but the KE4 stands out by having such a refined and consistent sounding treble that I don’t usually find in hybrids, let alone an isobaric hybrid IEM from Kiwi Ears. The extension and air is fantastic, the details are present but not overbearing and the overall energy level is just right. Obviously I’d want more, especially considering that the treble sounds the way it does mainly because of how thick the low end is, but I don’t mind the treble if the lower mids sounded a little bit thinner and the bass more midbass focused than subbass focused.

Technicalities​

Technically speaking, the KE4 sits right around what you might expect from the $200 mark. Good separation, superb dynamic and transients, solid resolving ability and good headstage. But arguably the best thing about the KE4 is coherency. Considering that this is Kiwi Ears second (correct me if I’m wrong) isobaric DD + BA hybrid, the KE4 is a home run in terms of tonal coherency. I did not feel like the bass lagged behind the mids or the treble, albeit there is still a little bit of a metallic tone in some songs. Dynamics and transients are decent, although definitely not the best that I’ve heard. Overall, good technical chops for the price but nothing too fantastic.

COMPARISONS​

vs Kiwi Ears Quartet​

I first want to compare the KE4 to its isobaric predecessor at half the price, the Quartet. I was not very impressed with the coherency and driver quality of the Quartet and thought that if it didn’t have that annoying metallic timbre up top, it would honestly be a pretty solid v-shaped set that sets itself apart by being as smooth as it is. The KE4 is a complete contrast with refinement being the name of the game and arguably dynamic and transient response. Raw tuning, I find the Quartet more fun and engaging. But that;s by design. The KE4 is neutral warm with a slight airiness while the Quartet is pure V-Shaped with big bass, scooped mids and big treble (spike). In short, the KE4 is not necessarily an upgrade to the vibrant and chaotic Quartet, but instead a more neutral-warm option that also features that isobaric DD hybrid configuration that Kiwi Ears flexed in the Quartet

vs Dunu Davinci​

Arguably the closest relative to the KE4 in configuration and tuning Philosophy, the Da Vinci is the KE4’s warmer, bassier and more fun cousin with a more engaging, punchier and deeper presentation that I personally preferred over the KE4. However, the KE4 is admittedly the more “balanced” option out of the two due to the rather big bass boost of the Da Vinci over the KE4. Coherency is similar on the two but the Da Vinci is certainly the more fun option to listen to between the two. The KE4 is you in the office and the Da Vinci is you on the beach. Same, well-rounded tuning with one of them letting loose and being a little bit more fun.

vs Simgot Supermix 4​

From isobaric to quadratic, the Supermix 4 imbues the previous tuning standard of the Harman 2019 compared to the JM-1 infused KE4. Flairs out of the way, the Supermix 4 is distinctly thinner and more vocal forward than the KE4 which is warmer and more relaxed. You could almost say they’re the exact opposite in terms of tonal balance, but the Supermix 4 is toned down from the usual Simgot tuning. Technically, the Supermix 4 has a cleaner sound out of the bat but the KE4 has a more consistent tone throughout the sound thanks to its flatter presentation. I’d say that both sets aren’t really my cup of tea (Supermix 4 having poor bass dynamics and KE4 having too much lower mids) but both sets occupy the opposite sides of the same nerdy coin.

vs Yanyin Canon II​

My favorite midrange fun hybrid still reigns supreme on what I find to be the ideal tuning for in-ears. While the KE4 offers a more relaxed and “neutral” tone, the Canon II offers a more engaging, more open and more detailed listening experience that would make perfect sense considering this is almost twice this price of the KE4. Giving the KE4 the benefit of the doubt, it is a generally smoother listening experienced compared to the Canon II. The Canon II suffers from a bit of a distinctly metallic and rougher treble presentation that both aids and affects its tonal presentation to not be the most neutral. But then again, that’s not why the Canon II exists in the first place and provides a more fun listening experience compared to the KE4’s more relaxed tone.

CONCLUSION​

Now, it all boils down to the burning questions. Does an IEM tuned to JM-1 sound good and what does this new HRTF spell for the future of in-ear monitors?

Let’s first talk about the KE4. Theoretically, the KE4 is the “safest” IEM to get under $200. The combination of a consistent tonal balance with good extensions on both ends, rich midrange, good details and technical ability. There’s technically nothing major to fault about the KE4 in a technical point of view. However, my preferences lie outside what the KE4 delivers. First, I like my midbass thick and meaty with the mids slightly scooped. The KE4 is the exact opposite with a very clean low end presentation and a borderline thick midrange presentation. Pair that with the upper midrange that lacks energy to my ears and sounds occasionally drowned in the lower midrange and you get a set that I’d only be picking up when I want to listen to retro pop and rock tracks that NEED that body. Not necessarily my “all-rounder” listening choice.

But that’s the thing about the KE4. Despite my personal comments on it, I still believe that this is an IEM that most people would probably thoroughly enjoy. Not only from my personal experience with talking to people and their preferences, but also the data gathered to create the JM-1 that the KE4 uses as a point of reference. Obviously, I don’t know if they actually did use the JM-1. But with how closely it follows the said tuning, you can’t deny that they are at least aware of what direction IEM tuning will go from this day onwards.

I believe that the JM-1 and to an extent, the KE4 is the right step to the evolution of IEM tuning. It may not be to my preference, but it’s certainly better than what we had before. This is less offensive and more balanced than the standard we’ve set for ourselves prior.

However, I also think it’s important that we understand that the JM1 is not a preference target to follow 1:1, but a preference boundary that we can modify depending on our own preferences. I may not like the JM1, but I know I like the Simgot EA500’s tuning and I can look at the frequency response graph to understand where the EA500 lands within the preference bounds. And the same can be said for every single IEM to come in the future that will use the JM1 as a point of reference to create their ideal IEM.

Thank you for reading my review on the Kiwi Ears KE4. If you would like to order one, consider using the non-affiliated link below: https://www.linsoul.com/products/kiwi-ears-ke4

RESOURCES:
Diffuse Field: https://headphones.com/blogs/features/diffuse-field
Understanding Headphones.com IEM measurements: https://forum.headphones.com/t/understanding-the-headphones-com-iem-measurements/23607
On the Standardization of the Frequency Response
of High-Quality Studio Headphones: https://hauptmikrofon.de/theile/1986-3_Standardization-of-studio-headphones_JAES-1986.pdf
The New IEM Meta Explained:

Introduction​

Kiwi Ears is among the most interesting brands that entered the Chi-Fi industry a few years ago, gaining a lot of attention both in the budget range and in the entry-mid-fi landscape.
In terms of Kiwi Ears products, the KE4 is the first product I have the pleasure to try from them, and I am happy that this happened with this particular set due to the hype around the JM-1 target (also called the “Meta Target”).

If you want to know more about the JM-1 “Meta Target”, this video from Minimum Phase is the one you should watch, as he is basically the guy behind the JM-1 target:

Disclaimer: the Kiwi Ears KE4 were sent to me by Kiwi Ears so that I could write an honest review. This review represents my personal opinion on the set, it isn't promotional or paid content and I don’t get any revenue from the sales of this product.
At the time of the review, the Kiwi Ears KE4 were on sale for about $199 at Amazon and Aliexpress. You can also buy them from Kiwi Ears website.

Click to expand...

Technical Specifications​

• Driver Configuration → 2 DD + 2 BA with a 3-way crossover network
• Impedance → 28 Ω ± 15%
• Spec-sheet Frequency Response → 20Hz-20kHz
• Nozzle Diameter → 6mm
• Sensitivity → 102 ± 1 dB
• Cable → 1.25m detachable copper cable with 0.78mm 2-PIN connectors
• Plug Type → 3.5mm

Packaging​

The packaging of the Kiwi Ears KE4 is rather simple and contains:

• The Kiwi Ears KE4
• The detachable 3.5mm cable with 2-PIN 0.78mm connectors
• One set of Kiwi Ears Flex tips
• Carry case
• User manual

Design, Build Quality, Comfort and Isolation​

The design of the KE4 is elegant and pleasing, and the neutral gray faceplate is not going to be fancy outside. The 3D resin printing is free from imperfections and the IEMs are very lightweight to wear and to carry.

The earpieces are very comfortable, the nozzle is long enough to grant a decent insertion depth and even though not the thinnest around it’s definitely not as uncomfortable as on other IEMs that have very thick nozzles. I think the brand should have included one more set of different ear tips at least.
The passive isolation is pretty good too.

Cable​

I was expecting a slightly nicer cable to be honest. Not to say that this is bad but it’s prone to tangling and the competition is fierce as there are also very cheap IEMs that come with cables of similar quality.

Sound​

GEAR USED FOR THE TEST

• DAC: Topping E30
• AMP: Topping L30, Fiio A3
• Mobile phones: Samsung Galaxy S7 Edge, Xiaomi Mi A3, Samsung Galaxy S23 Ultra
• Moondrop May’s DSP cable with PEQ=0
• Dongle: Apple Type-C dongle, Fosi DS2, Hidizs XO
• Portable DAPs: Benjie S8/AGPTEK M30B
• Bluetooth Adapters: KBEAR S1, KZ AZ10
• Other sources: Presonus AudioBox iONE, Elgato Wave XLR

Do they need an amplifier?
No, an amplifier is not strictly needed, but I have noticed that a good amplification helps the low-end robustness and the overall dynamics.

Sound signature
The Kiwi Ears KE4 are tuned following the JM-1 target, also called “Meta Target” by many people on the web. It’s basically a very versatile and relaxed IEM and sports a touch of sub-bass boost which makes it a smooth warm-neutral set.

Lows
The lows are presented without excesses or coloration, with nice depth and sub-bass extension yet with limited bass punch. The mid-bass, in fact, is not the star of the show, even though it’s present and sometimes gently bleeds into the midrange to give a very soft warm touch.
It’s not the contrast-y and rumbling low end you’d expect from a fun-oriented set, and in fact this is a set that I would never recommend to folks that are used to more energy in the sub-bass and bass region.
If anything, this means that the overall bass response is tendentially fast with medium-to-short decay, leading to a less textured and thick bass. Sometimes I was searching for some more energy and contrast as I didn’t start moving my feet while I was listening to music with the KE4, but this is something very subjective and I think the low-end is correctly represented if your intention is to buy a relatively flat or neutral set.

Mids
The midrange is not recessed, with the lower mids having a touch of added warmth and a bit more thickness than your usual Harman tuned IEM. Male vocals sound more correct on the KE4 and they are not left behind female vocals or behind the low end, and female vocals sound balanced without becoming hot or sibilant, even though sometimes they lack some air.
The instruments are correctly separated but this kind of tuning leaves slightly less space than a classic V-Shaped or U-shaped tuning, providing for a less deep soundstage in which the instruments, that are reproduced in a very natural manner, can be placed.

Highs
The highs are neither for those who like dark or warmer signatures with very noticeable treble roll-off nor for those who want a very exciting and sparkling upper end. It’s not the typical contrast-y treble one can find on a V-Shaped set, but it’s not missing air and details. The treble extension is pretty good in fact, and the KE4 never sound closed-in. The overall resolution and detail retrieval is spot-on for the price and considering the tuning and there’s no sibilance also, which is good news.
If I had to be very nitpicking, a very small touch of BA timbre can pop-up in certain cases, yet only when the volume is pretty high and when particular sounds are being reproduced.

The soundstage width is pretty nice considering the tuning, whereas the depth and height are slightly less surprising. The imaging is good, whereas layering is well done even though it’s not an effortless task for the KE4 when very complex and/or busy tracks are being reproduced (the good low-end control really helps with this matter, no doubts).

Some comparisons:​

Kiwi Ears KE4 vs Celest Relentless
They are very different since the Relentless are V-shaped whereas the KE4 are warm-neutral with sub-bass focus. The Relentless are colored, vivid, open-sounding and very sparkling, with prominent low-end punch and a very engaging sound yet with some sacrifices during long listening sessions, such as some treble sharpness and a recessed midrange. The KE4 are very relaxed instead, buttery smooth with a more forward and richer midrange, more balanced and more natural vocals yet with less vividness and contrast and with slightly inferior technicalities and resolution. Soundstage and imaging is good on both though, which is good news.
Even though my preference for the Relentless is evident (I like some coloration), I think it would be a lot easier for me to suggest the KE4 to almost everyone, whereas the Relentless are harder to recommend due to them being very bright and less versatile.
In terms of design, build quality and comfort, I think the Relentless have a slight edge, whereas the isolation is very similar. The Relentless come with a much better cable and a wider set of tips.

Kiwi Ears KE4 vs Simgot Supermix 4
There’s no winner in terms of tuning as it all comes down to personal preferences, but it’s pretty clear that the Supermix 4 is more fun to listen to, punchier, more resolving and more detailed.
The KE4 provide for a much more balanced sound reproduction instead, with less intense female vocals, slightly thicker male vocals than the average Harman-tuned IEM and a less bright yet well extended treble response.
If I had to describe them, then the KE4 would be the smooth and relaxing IEM I’d pick to sit on the sofa and listen to some music in front of the fireplace, whereas the Supermix 4 would be the one I’d carry with me when traveling.
In terms of build quality, they are both well built and use different materials. The Supermix 4 are slightly heavier, whereas the KE4 are more lightweight. Both are very comfortable whereas the isolation is a touch better on the KE4.
The Supermix 4 come with a better cable but the KE4 come with better quality eartips (both companies could include some more tips in the box, though).

Kiwi Ears KE4 vs AFUL Explorer
The AFUL Explorer is a very unique set in its price range and the KE4 seem like the best option for those who didn’t dislike the Explorer yet felt like they were a bit too closed-in and slightly unnatural.
Both have a sub-bass focus but the KE4 are better at everything: better vocals, more natural instruments reproduction, better detail retrieval, a much more expansive soundstage, better imaging.
What’s better on the Explorer? The size of the shells, which is much smaller than on the KE4, the included stock cable and the stock tips variety.
The price is very different though, so that’s another thing to take into account.

Kiwi Ears KE4 vs Truthear Hexa
What about the HEXA?
Well, the KE4 kind-of do well where the Hexa didn’t: a bit more thickness in the low-end and in the lower-midrange, and a more relaxed mid-treble. The KE4 provides for a more refined and natural sound approach, but it’s safe to say that the HEXA still compete very well in terms of technical performance and the two aren’t very distant under this aspect (this is a true endorsement for the Hexa).
I don’t know if I’d spend more than twice the price of the HEXA to get my hands on the KE4, if I were searching for a technical upgrade, but this is also coming from a person (me) who really like the HEXA the way they are, so if you are also searching for a more refined and natural tuning then the KE4 might be worth the jump.
In terms of comfort, both are nice, whereas the isolation of the KE4 is better. Build quality is good on both but the resin shells of the KE4 are of slightly better quality.
When it comes to the included cables, both are just ok, whereas in terms of included tips the HEXA win hands down (more variety and sizes).

Final Thoughts​

The KE4 are versatile and are characterized by a very safe tuning that is easy to recommend to almost everyone. The overall balance across the frequencies is pretty good, and this comes along with a nice soundstage and imaging to make sure that every track is reproduced in a proper way. That said, the KE4 will probably be too safe/boring for some people and not ideal for those who really want to get excited during their listening sessions.

Let’s say that if you want the most vivid and the most impressively technical set in this price range, then I’d suggest you look for something else, but if you are on the market for an easy-to-drive warm-neutral set to sit and enjoy your music, no matter what’s your favorite genre, this is what I’d suggest for this amount money, as I really struggle to find true cons with the KE4 in my ears: I have been using them since last month and they have become my go-to at home (not my commuting daily IEMs though, as I prefer sets that are more engaging for that purpose).

Well done Kiwi Ears, hopefully I’ll be able to test some of your future sets as these really grew on me and I can’t wait to try something new.

Disclaimer: Kiwi Ears provided me with a review unit. All thoughts and opinions are my own.

Introduction​

Kiwi Ears in 2024 has been on a very strong push in their product lineup, releasing various IEMs with different driver configuration and tuning approaches. Their latest entry, the KE4 ($199), is a hybrid 2DD+2BA IEM with the “new meta” tuning (often called JM-1, or just “Diffuse Field with bass tilt”) that has been quite popular for a few months at the time of writing.

Since it is likely that there will be plenty of other IEMs aiming at the "new meta" target, how did the KE4 perform as one of the first few? Let’s find out!

Packaging, Build & Specifications​

Driver configuration:

• 2x Custom 10mm dynamic drivers in isobaric configuration as subwoofer
• Custom RAB-32257 for midrange
• Knowles RAD 33518 BA for treble
• 3-way crossover

Impedance: 28Ω
Sensitivity: 102dB (±1dB)
Connector: 0.78mm 2Pin

As far as packaging goes, KE4 went for a simplistic route: the IEM itself, Kiwi Ears Flex eartips, a hard carrying case, cable with 3.5mm termination, and usage manual. There is no option for 4.4mm or modular termination sadly.

The carrying case is the standard zippered hard case that was included in other Kiwi Ears models, so it is pretty okay to me. The 3.5mm cable is decent, but on the thinner side. The eartips included is the Kiwi Ears Flex, which I happen to previously tried and liked a lot (by the way, they are $15 when sold separately). I would say the accessories are not the best, but also not terrible.

Sound Impressions​

Sources: L&P W2 Ultra, Hiby R4 Evangelion, FiiO JA11, KA15, M23, SMSL H300+D300 stack
Setup: Kiwi Ears Flex L tips, stock cable, YongSe WhiteBear 4.4mm cable (for testing with balanced)
Music Sources: Youtube Music, Tidal, Lossless FLACs

The IEM has undergone a 24-hour burn-in at a medium volume prior to the review. Listening impression is a very subjective experience depending on individual ear shape, choice of eartips, music library, and personal preferences, so your experience may vary. I personally listen mostly to pop, jazz, some rock, and very limited metal.


Using third-party YongSe WhiteBear 4.4mm cable for testing with balanced connection

Other earlier reviews have made references to the so-called “new meta” tuning that KE4 has closely adhered to, intentionally or not. Just a quick explainer, the “new meta” is the target that was constructed by adding bass boost (tilt) to the Diffuse Field target on B&K 5128 within preference bounds (okay, that’s still kinda wordy). If I have to describe it myself, I would describe KE4 as sounding as neutral with bass boost.


Measurement is taken with a clone IEC711 coupler with foam tips

KE4 starts off with a smooth and quite bloomy subbass that transitions to bass shelf to the mids, giving off that laid-back yet clean presentation. I was expecting a tighter bass response, considering that it is powered by isobaric dual DDs, but KE4 does allow the bass to have a longer decay to give it more body and thickness to the tone. However, due to the laid-back presentation, the bass texture suffers a little bit, although this is not really a big issue especially if it is paired with certain sources. In grander tracks such as “Dreams of Arrakis” from Hans Zimmer, the boomy bass makes such an immersive sensation.

In the midrange, KE4 performs very well: clean and clear. Vocals are leaning towards the thicker presentation, having some kind of “throatiness” to male vocals especially. That said, instruments in this region are not very forward, somewhat a bit behind the vocals. The midrange resolution is pretty good with more emphasis on the macrodetails than microdetails. In “Kaiju no Hanauta” by Vaundy, the vocals certainly took centre stage, capturing the emotion and nuances very well.

Treble of KE4 would be considered pretty “safe” overall. There is no sibilance nor sharpness, while keeping good enough air and resolution overall. The treble extension is also pretty good. That said, it might lack a certain “bite” that might be needed to capture that excitement in some tracks. While listening to “Scars of Time” orchestral piece by Yasunori Mitsuda, I found that the safe-ness of the treble tuning does affect my listening experience, but overall it is still very enjoyable.

As for technicalities, I find them a bit middling, especially compared to the competition in the same price range. The soundstage is not the widest, but the imaging is quite accurate. Layering and resolution are acceptable for the price, but it seems that KE4 is trading them off for more pleasant timbre and tonality. Coherence is quite good as well, and dynamics are very competent, handling transients in busy tracks adeptly.

Power Requirements and Pairing Suggestions​

KE4 is relatively easy to drive, even from cheap dongles like FiiO JA11. However, sources with tighter, more controlled bass would be preferable so as to not make the bass too bloomy. I found that my W2 Ultra and H300 did a very good job at that, as well as the KA15.

Select Comparisons​

Simgot SuperMix4 ($150):
The SM4 is definitely a more technical set, tuned more aggressively U-shaped/Harman. In comparison, KE4 is warmer and more laid-back overall, with a more relaxed uppermids and treble. There are indeed some tracks that are better with SM4, and some more enjoyable with KE4, but since the presentations of both IEMs are very different between the two, it comes down to taste and musical preferences. If you are someone looking for a micro-details focused and technical set, SM4 might be a better choice. For someone who is looking for a laid-back, musical, warm IEM, KE4 would be a better choice. Lastly, KE4 is also noticeably easier to drive than SM4.



SeeAudio Yume Ultra ($220):
The Yume Ultra is also a somewhat vocal-focused IEM with a similar level of technicalities as the KE4. The biggest difference between them is the bass quantity and quality. Yume Ultra is very subbass-focused, leaving a very lean midbass. The vocal is also even more forward than the KE4, but without the thickness that KE4 presents. Personally, this is very genre-specific. For Yume Ultra, it seems that pop (especially J-pop and K-pop) would be more suitable, whereas KE4 is more suited for jazz and ballads (and also many more, a lot more versatile than Yume Ultra). That said, I find the KE4 has a more pleasant tonality overall and less fatiguing in long term listening.

Conclusion​

Kiwi Ears KE4 is a very competitive IEM with pleasant, laid-back tuning and decent technicalities. Regardless of the “new meta” label attached to it, I think it is an IEM that is very easy to enjoy, versatile in various usage scenarios, and can stand on its own merits. I can easily recommend the KE4.

Configuration: 2x DD / 2x BA
RRP: $199



Introduction

Kiwi Ears has built quite a loyal customer base over the past year or two, offering IEMs ranging from sub-$100 options to around $500 for their all-BA model, the Orchestra. I briefly owned the Quintet about a year ago, and while I was impressed with it for the price point, it landed during a time when I had several other sets on the go. It ended up being neglected, as often happens in this hobby, so I moved it along as part of the hobby rollercoaster many of us are familiar with. One morning a few weeks ago I received a nice message from Evelyn at Kiwi Ears, inviting me to try out the KE4. As always, I’m curious to hear new sets, and even more so when I saw that the KE4 features two dynamic drivers—a real soft spot of mine. Needless to say, I was happy to give them a shot. Oh and of course I was curious to hear what this ‘meta’ tuning was all about, now I know… tldr; pleasant!

A big thank you to Kiwi Ears for the opportunity! As always, no silver crossed my palms to influence the following thoughts, all opinions and photos are my own…



About Me…

I worked in the consumer electronics industry for a large part of my career and have been passionate about music and technology for as long as I can remember. Even as a small child, I would ask my mum to put records on the turntable (Abba, Supertramp, and Planxty if anyone is curious).

My music preferences are very varied—anything from classical to techno, indie rock to jazz, and everything in between. In my early teens, I was a big fan of bands like The Cure and The Smiths (still am all these years later). I was bitten by the dance music bug in the early 90s, becoming passionate about genres like techno, house, trance, and IDM. I amassed a huge collection of records and CDs, DJing at various parties and occasional pirate radio station slots. Although it remained a hobby, I still own thousands of records, and my trusty Technics 1210 turntables are still going strong 30 years later—a testament to Japanese engineering!

I am not a professional reviewer, just an enthusiast who loves music and the devices we use to listen to it. Over the last few years, I have become obsessed with IEMs and related gear. I've bought and sold many, and kept a select few—ranging from the $20 Moondrop Chu to kilobuck sets like the Aroma Jewel, Oriolus' infamous 'Traillii,' UM Mentor, and various beloved single DDs. Through this exploration, I like to share my thoughts with the Head-Fi community, hoping they might be useful to others. However, remember that this is a highly subjective hobby, and your mileage may vary.

While I've been fortunate to own and try a variety of the TOTL sets on the market, I honestly enjoy lower-priced sets as much - especially as the gap continues to close, many much cheaper sets now offering significant value and further driving diminishing returns.

I’ll admit I do suffer from happy ears—rarely do I find an IEM that I genuinely dislike. At this stage, there are very few truly "bad" IEMs; it all comes down to individual preferences. Since I listen to such a wide variety of genres, I almost always find synergy with some part of my library. Where I tend to deduct marks is in areas like value for money, poor accessories, or an uncomfortable fit—things that can detract from the overall experience.

Specifications

Drivers: 2 Balanced Armatures, 2 Dynamic Drivers, 1 Knowles RAD-33518, 1 Customized RAB-32257

• Driver Details - 1 Uitra-High Frequency Driver, 1 Mid-High Frequency Driver, 2 Low Frequency Drivers
• Crossover - 3-Way Crossover Network
• Sensitivity - 102dB (±1dB)
• Impedance - 28 ohm

Unboxing & Accessories



Pretty straightforward unboxing here—a compact box with the KE4 nestled on top, and underneath, you’ll find the case and a warranty booklet.





Inside the case, you get the cable and a set of ear tips. The cable itself is decent, but I do have a small gripe: there’s no modular system or option for a 4.4mm plug, only 3.5mm. At this price point, I’d expect at least the option to choose, if not a modular cable system, which is becoming the norm at this level. That said, the stock cable is light, soft, and microphonics are minimal.

As for the tips, I can’t comment on the fit—none worked for my larger-than-usual ear canals! They seem good, though, and I’ve heard positive feedback. If Kiwi Ears could release an XL version for us large-ear-canal folks, I’d be very pleased... For now, I’m using my trusty Acoustune AET07s, which I’ve relied on for about three years now, and also more recently the newer AEX07 which are fantastic too.

Fit & Design

The KE4 shells are medium-sized, very lightweight, and fit beautifully in my ears. They’re super comfortable, even for extended listening sessions. I personally like the understated design—a simple silver faceplate with the Kiwi Ears logo, nothing too flashy.

Fit is subjective, of course, but I’d be surprised if anyone had issues here. No sharp edges or overly long nozzles to jab into your brain! I’ve used them regularly over the past few weeks, whether walking the dog or taking lunch breaks in Dublin city centre. The isolation is solid, enough to block out city noise, and the comfort allows for extended listning sessions.



Listening Impressions

From the moment I first plugged in the KE4, my immediate thought was, “pleasant.” The tuning is smooth, balanced, and warm-leaning—nothing jarring or offensive. It’s an all-rounder type of sound that I think most people will appreciate, though those looking for an exciting or hyper-detailed presentation may find it a little too relaxed. And if you’re into extended treble sparkle, the KE4’s top end might feel a little too laid-back.



Bass

The tuning definitely favours the sub-bass, which digs deep with a satisfying, visceral rumble. However, the mid-bass is slightly softer than I’d prefer—it delivers impact but lacks that refined, hard-hitting slam that some listeners will crave. The smoothness from the bass flows naturally into the mids, making them feel lush and engaging. The timbre sounds accurate to my ears, offering nice realism with lower registers of synths, piano, strings etc.

Midrange

There’s good clarity in the midrange, with a well-layered and spacious presentation. Male vocals might come off as slightly thin at times, but that’s a minor nitpick—they sit well within the mix, neither too forward nor recessed, maintaining a balanced placement alongside the instruments. The upper mids extend reasonably well and without any harsh peaks, allowing female vocals and instruments that dip into this range to create an emotive and captivating experience. I haven't experienced any real sense of congestion even with the busiest of tracks.

Treble

As noted earlier, the KE4 won’t satisfy treble-heads, as the highs are relatively subdued. However, it’s not as if the treble is absent, it just takes a backseat, which equally ensures no sibilance or harshness creeps in. Percussion for example is rendered well and the treble still contributes to the KE4’s overall clarity and sense of imaging.

Technical Performance

One of the first things that struck me was the KE4’s imaging. While I wouldn’t describe it as pinpoint accuracy—the level of resolution needed for that is higher—it does a great job of positioning instruments and vocals with a softer and cohesive presentation. The soundstage has decent width, though it’s not the widest. As for micro-detail, it’s not a strong point, but you can still catch all the essential elements in the music. Just don’t expect a microscope on the tiniest details… this is a set that is tuned towards a more musical experience.



Test Tracks

I’ve had the KE4 paired with a variety of sources over the past few weeks, including the Aune M1p, Sony ZX300, ZX707, 1A, and 1ZM2. However, I've found myself reaching for the ZX300 the most, as it creates a fantastic portable combo for walks, commutes, and daily outings… especially my morning dog-walk routine – many IEMs have been put to the test on these morning walks!

Pictured below with the ZX300 and using a Tripowin balanced cable... a regular combo lately!



Phosphorescent – Around the Horn

https://phosphorescent.bandcamp.com/track/around-the-horn

Kicking off this section with an indie gem from the brilliant Phosphorescent. As mentioned in the mids section, vocals on the KE4 come across as slightly thin and sit level with the instruments. However, the instruments themselves have ample space to breathe, and this track has plenty of layers to explore. While it’s easy to pick out each instrument if you focus, the KE4 draws me more so into the overall composition. The KE4 does a splendid job here—foot tapping, grin-inducing—and when the instrumental mid-section leads into the reintroduction of vocals, it sends shivers down my spine. The timbre is spot-on, and everything feels wonderfully cohesive. It’s hard to find fault here!

Nexus 23 – Mental



And now for something completely different, as Monty Python would say (a nod for those who know). This is a belting techno track, a clear departure from the previous test. I was eager to throw a fast-paced techno number at the KE4, and it didn’t disappoint. The mid-bass stands out, though I do find myself wishing for a bit more definition in the slam. That said, it doesn’t take away from the overall experience—the pounding, relentless quality is still there, driving the track forward and laying down the foundation, as is typical with this genre as the track unfolds and evolves. It’s engaging and certainly keep me immersed in the rhythm throughout. Sidenote, way too long since I’ve listened to this album and fully intend to give it a spin on a morning walk this week… although given the pace, it might become a jog…

Julien Baker – Relative Fiction

https://julienbaker.bandcamp.com/track/relative-fiction

The timbre accuracy strikes me immediately with this track, instantly captivating me with the blend of instruments and Julien's beautiful voice. There's a lovely weight to her vocals, with absolutely no hint of sibilance, and as noted I do find that the KE4 shines more with female vocals than with male. The instruments are incredibly clear and well-positioned within the soundstage. This stage evokes a sense of intimacy—think of a small gig venue where you're just a couple of seats from the stage. Overall, the presentation here is both engaging and heartfelt, impressively so at a sub-$200 price point.

Stars of the Lid – The Lonely People (Are Getting Lonelier)



As a long-time fan of Stars of the Lid, I often turn to their music when I need calm or a gentle nudge toward sleep. Interestingly, this is my first time testing any of their tracks for a review, so I was eager to see how the KE4 handles their unique sound. With this style of music, my main focus is on how captivating the experience is, as most of the activity resides in the mid-range, and complexity is rarely a factor. The sub-bass plays a key role too, as the lower synth registers emerge to create a visceral and engaging atmosphere. While the KE4 delivers a pleasing and emotive experience, I find myself wishing for a more expansive stage size—something I often seek in this genre... Still an admirable job, and I certainly wouldn’t be inclined to pull them out of my ears… oh and another album I must revisit, and indeed Stars of the Lid in general.



Conclusion

While it may not cater to listeners chasing the thrill of ultra-detailed, exciting or analytical tuning, the KE4 excels as a smooth, warm, and engaging all-rounder. Its tuning works across a wide variety of genres, offering a non-fatiguing experience that's enjoyable over extended sessions… coupled with excellent comfort, the KE4 is a solid choice for anyone looking for a safe, reliable IEM that consistently delivers, especially at this price point. I would prefer to see at least an option for a 4.4mm cable, and ideally something modular, and indeed a bit of a step-up in terms of accessories, certainly a wider selection of tips at this price level. Overall though, an impressive set if the boxes ticked meet your preferences!

This is the second Kiwi Ears product I've tried; I previously tested the Cadenza early last year and admired its warm tuning, which is perfect for relaxing without the fatigue that comes from brighter, and more analytical set. I was offered a review opportunity for the KE4, so thanks to them for trusting me to evaluate. however, i ensure my review will be honest, and again this hobby is very much subjective, so approach my reviews with a critical eye.

The KE4 has a non-typical Harman curve and is being called the new "Meta Tuning". I’m excited to see if it lives up to the hype, The anti-Harman aspect is always fascinating to try! But before discussing the sound, let’s talk about the non-sound aspects, Starting Packaging and accessories.




The IEMs come in simple packaging that’s medium-sized, inside:
- The IEMs
- The cable
- A case
- 2 pair of nozzle filter
- Kiwi Ears Flex eartips



While there aren’t any additional items, for me the offered accessories meet basic needs. The cable is quite standard—not thickly braided but rather soft and slim, making it comfortable to wear, but a bit prone to tangles. The new Ears Flex eartips are interesting and unique; and it's great to have something other than generic one.

Design, Build, and Fit





These IEMs feature a minimalist design with a clear faceplate that adds to the simplistic look, with brand tag "Kiwi Ears" inside. The build quality feels solid, made with 3D medical resin, which is also lightweight and provides good noise isolation. Comfort is excellent with its quite short nozzle, but this can be a bit limited choice of eartips that will fits, also the ear hooks on the cable are flexible and not bothersome during use, just add more comfy to it.

The Sound

Now it’s time to discuss the sound. Straight of from the box, these IEMs have a very safe and relaxed sound, especially since I had been using bright IEMs with a strong emphasis on treble 24/7. I needed to acclimate to these IEMs and let my brain "burn in" for about 100 hours. Now, I can describe the tuning as neutral to warm, which is ideal for those who enjoy a laid-back sound. Treble-sensitive listeners will likely appreciate its forgiving nature.

Bass

I find that the bass leans more towards sub-bass focus, with nice lingering decay. For those who don’t enjoy this type of bass and are sensitive to sub-bass, the long decay can be fatiguing at times. The mid-bass isn’t very punchy or impactful rather has nice thump, making it suitable for genres like R&B, Pop, and or alternative rock still very enjoyable. However, with this decay, I’ve found it doesn’t perform well with hard rock or fast bass tracks; its just can't keep up to it's thouderous drum beats and the double pedal. Objectively, the bass has good quality with pretty nice depth, but subjectively, it’s not my favourite kind of bass.

Midrange

The midrange is my favorite aspect, also this probably one of the safest upper in its class. While listening to K-pop and J-pop, I usually find the upper midrange slightly piercing, but here it’s well-controlled and doesn't has high sharp from the 'S' sound or sibilance, There’s are slightly hint only on certain tracks, which doesn’t distract. The lower midrange has good note weight and doesn’t sound thin, making it equally good for both male and female vocals. The vocals are good especially listen for listen folk tracks, but for females with high pitch this can come across as lack energy; but overall, the midrange has an organic sound.

Treble

The KE4 has treble that won’t hurt your ears, especially if you’re sensitive to treble. It retains a articulate, such as in acoustic guitar, which sounds nice, but with the upper mid to treble doesn't have high empass enough, soo for electric guitar sounds, it can feel somewhat restrained. If you’re a fan of progressive rock that enjoys a bright, crisp sound, on string guitar you might find it lacking. Also The cymbals aren’t snappy, but somehow thier are slightly has shimmer sound. This might indicate a timbre issue common in BA hybrid sets, but honestly, it doesn’t bothersome and mostly goes away after many uses. Overall, with this kind of treble seems suitable for most people, especially for relaxed listening.

Technicalities

The soundstage is quite wide with notable good depth, and I find the imaging to be accurate. However, the resolution feels a bit average, especially when paired with warm sources. for my recommendation pairing these IEMs with neutral to bright sources is a bit required.. The micro-detail for the price is good; it captures tiny nuances but don’t expect analytical-level detail. and Separation and layering on this iems depend on the tracks or genre you listen; R&B, pop, or power ballads still commendable, but complicated tracks like hard rock, funk rock, especially metal can be challenging due to the bass not being tuned for genres that require speedy and impactul low-end...



Conclusion

I believe these IEMs will suit many people, especially for those looking for a chill tuning or who are tired of the energetic Harman curve that emphasizes the upper range. If you love rock or metal, definitely look elsewhere, but for someone who wants to appreciate chill and mellow tracks, this could be a top choice.

Where to Buy? Its available from various online retailers, including

https://kiwiears.com/products/kiwi-ears-ke4

https://www.linsoul.com/products/kiwi-ears-ke4

Preface:

You can purchase KE4 at the following link (not an affiliate link):
https://www.linsoul.com/products/kiwi-ears-ke4?_pos=11&_fid=f63c0f215&_ss=c

Also, I’m not a seasoned reviewer, so whatever I say is purely my observations and your results may vary.

I’m not the one to usually focus on specifications and numbers. I focus more on how happy I am with the equipment’s sound and that’s it.

Disclaimer: This is a review unit from Linsoul however I retain full editorial control and the opinions expressed here are solely my own. I have not been paid or compensated by Linsoul, Kiwi Ears or any other entity for this review. My assessment is based solely on my personal experience with the product.

I do get to keep the unit after review but that had no influence over the opinions expressed below.

Sources used:

• Dita Navigator
• iBasso DC07 Pro
• iBasso D16 Taipan
• FiiO M17
• RME ADI-2 Pro FS R
• Gungnir + XI Audio Broadway S

Introduction:
Kiwi Ears, hailing from China, has been making waves in the community with their impressive lineup of IEMs. They've consistently delivered strong performers like the Quintet, Orchestra, Orchestra Lite and Cadenza, each with its unique sonic flavor. Now, they've introduced the KE4, aiming to capture a more natural and engaging sound signature.



Box Contents:

• IEMs
• 0.78mm 2-pin Cable (3.5mm terminated)
• 03 pairs of silicone tips (S/M/L)
• 02 pairs of Nozzle covers
• IEM carry case

Design and Build:
The faceplate has a brushed aluminum look with 'Kiwi Ears' logo in the center. It's definitely eye-catching without being overly flashy. The shells themselves are made of resin, and they feel solid and well-put together.

The shells themselves have a smooth, ergonomic shape that fits comfortably in my ears. The nozzle has a slight lip that helps keep the ear tips secure, and the overall fit is snug and isolates well.

While the included cable is functional, it's fairly basic and a bit prone to tangling. I'd likely upgrade to a nicer cable at some point to improve handling.















Sound Analysis:

Tonality:

The KE4 aims for a natural and balanced presentation with a slight warmth that makes it engaging without being overly colored. This tuning makes it versatile across genres, though it truly shines with acoustic music and vocals, like the intimacy and emotion in Stevie Nicks' voice in "Landslide" by Fleetwood Mac. The KE4 beautifully captures the subtle nuances in her voice, the delicate fingerpicking on the acoustic guitar, and the harmonies. This balanced approach is equally evident in "So What" by Miles Davis, where the trumpets have a natural brassy timbre, the double bass has a weighty presence, and the drums have satisfying impact without overshadowing other instruments.

Sub Bass:

The sub-bass region extends decently deep, providing a solid foundation for music with a strong low-end presence. While it doesn't have the most impactful rumble, it's well-controlled and avoids any bloat or muddiness. In "Angel" by Massive Attack, the deep bassline that underpins the track is reproduced with adequate depth and texture, adding atmosphere and weight without becoming overwhelming. However, in "Radioactive" by Imagine Dragons, the synthesized sub-bass lacks the visceral impact I've experienced with some other IEMs. It's present and adds to the overall atmosphere, but it doesn't quite reach the deepest depths.

Mid Bass:

This is where the KE4 truly excels. The mid-bass is punchy, textured, and well-defined, making it a joy to listen to genres that rely on a strong rhythmic foundation. The iconic bassline in "Billie Jean" by Michael Jackson is reproduced with excellent definition and impact. Each note is distinct and punchy, contributing to the song's infectious groove. Similarly, in "Seven Nation Army" by The White Stripes, the driving bassline is full of energy and texture. The KE4 captures the raw power of the bass guitar while maintaining excellent control and definition.

Lower Midrange:

The lower midrange is slightly forward, which adds warmth and body to male vocals and instruments like cellos and baritone saxophones. This is evident in "The Sound of Silence" by Simon & Garfunkel, where the richness and depth of their voices are well-represented, creating an intimate and engaging listening experience. However, this emphasis can sometimes lead to a slight lack of clarity and separation in this region, as heard in "Paradise By the Dashboard Light" by Meat Loaf, where the denser instrumentation in the lower midrange can sound a bit congested, particularly during the more dynamic passages.

Upper Midrange:

Female vocals and instruments like violins and guitars are presented with clarity and detail in the upper midrange. Adele's powerful vocals in "Someone Like You" are reproduced with emotion and accuracy. The KE4 captures the nuances in her voice, conveying the raw emotion of the song. While generally well-represented, they could benefit from a touch more air and presence. In "Violin Concerto No. 1 in G Minor" by Max Bruch, the violin has a clear and detailed presentation, but it lacks a bit of the "sparkle" and airiness that I've heard with other IEMs.

Lower Treble:

The lower treble region is smooth and well-controlled, avoiding any harshness or sibilance. Cymbals and hi-hats have a natural shimmer without sounding overly sharp or fatiguing. This is evident in "Take the 'A' Train" by Duke Ellington, where the cymbal crashes are crisp and well-defined, adding a sense of rhythm and energy to the music. In "Wish You Were Here" by Pink Floyd, the acoustic guitar has a natural timbre, and the subtle details in the recording are easily discernible.

Upper Treble:

The upper treble extends well, contributing to a sense of air and spaciousness in the overall presentation. In "Clair de Lune" by Debussy, the piano notes have a delicate shimmer that adds to the ethereal atmosphere of the piece. The upper treble extension contributes to a sense of air and space. However, there's a slight peak in this region that can occasionally emphasize certain high-pitched sounds, like the high notes in Freddie Mercury's vocal runs in "Bohemian Rhapsody" by Queen, which can occasionally sound a bit sharp and emphasized during the climax of the song however it was nowhere near being unbearable to listen to.

Staging:

The KE4 offers a respectable soundstage with good width and depth, creating a sense of space and immersion. In "Hotel California" by the Eagles, the instruments are positioned well across the soundstage, creating a sense of depth and separation. The guitar solos, in particular, have a good sense of space and positioning. In "Comfortably Numb" by Pink Floyd, the expansive soundscape of the song is well-represented, with the various instruments and effects spread out nicely. While the height is adequate, it's not the most expansive I've encountered.

Layering and Separation:

The KE4 does a commendable job of layering and separating instruments, allowing individual elements to be easily distinguished even in complex musical passages. In "Bohemian Rhapsody" by Queen, the multiple vocal harmonies, guitar lines, and piano melodies are well-layered and separated, preventing the track from sounding congested. Similarly, in "A Day in the Life" by The Beatles, the various orchestral instruments and sound effects are clearly defined, which allowed me to appreciate the intricate arrangement.

Timbre:

KE4 generally presents instruments with a natural and realistic timbre, making them sound authentic and engaging. In "Tears in Heaven" by Eric Clapton, the acoustic guitar has a convincing texture and tone, capturing the emotion of the song. Similarly, in "Hallelujah" by Leonard Cohen, his vocals are rendered with a rich and natural timbre that adds to the song's emotional impact.

Detail Retrieval:

The KE4 excels at retrieving details in the music, allowing the listener to hear subtle nuances that might be missed with less resolving IEMs. In "Strawberry Fields Forever" by The Beatles, the various studio effects and psychedelic elements in the recording are clearly audible, showcasing the KE4's ability to reveal subtle details. In "The Great Gig in the Sky" by Pink Floyd, the nuances in Clare Torry's vocal performance are captured with impressive clarity, allowing the listener to fully appreciate her emotional range.

Conclusion:

The Kiwi Ears KE4 is a well-rounded IEM that excels in many areas. It offers a natural and engaging sound signature with a punchy mid-bass, good detail retrieval, and a respectable soundstage. While it may not be perfect in every aspect, its overall performance is impressive especially at a price point of $200.

Linsoul Store links:

Linsoul website: https://www.linsoul.com/
Linsoul Aliexpress Store: https://ddaudio.aliexpress.com/store/2894006
Linsoul USA Amazon Store link: https://www.amazon.com/s?me=A267P2DT104U3C&marketplaceID=ATVPDKIKX0DER

thaslaya's star rating system:
☆☆☆☆☆ - Fantastic!
☆☆☆☆ - Recommended
☆☆☆ - There are buyers but not for me
☆☆ - Can't see the appeal
☆ - Product is a failure

Disclaimer:
This product was provided to me by Linsoul in exchange for my impartial and honest review. I recieve no compensation and all thoughts and opinions are my own. A special thanks to Carina at Linsoul for coordinating this unit for review.

Non-affiliate link for those interested:
https://www.linsoul.com/products/kiwi-ears-ke4?variant=45846825763033

Gear used:
●LG v30+
●Samsung Galaxy s22 Ultra
●iBasso DX180
●Samsung dongle
●Hiby FC4
●Kiwi Ears Allegro
●Letshuoer DT03
●Dunu DTC480
●BLON V1

Source:
●Listening was done through Amazon Music HD or Ultra HD.


Introduction:
Kiwi Ears' releases have been somewhat hit-or-miss with me personally and, it seems, the community at large. Some IEMs like the Cadenza are still highly regarded in the budget tier. Others like the Quartet and Melody received overall less-than-stellar reviews. I still use the Allegro DAC/amp in most of my reviews, and the Orchestra Lite quickly climbed the ranks to become my favorite all-BA set to date, so I know Kiwi Ears makes some really great stuff. Their most recent IEM is the KE4, a hybrid featuring two dynamic and two balanced armature drivers. It is available on Linsoul for $199. There's also a bundle that includes the new Kiwi Ears Allegro Mini amplifier for only $10 more. Let's break down this newest hybrid from Kiwi Ears and see how it stacks up.


Build, fit, ergonomics:
The packaging and unboxing are a bit utilitarian and similar to other Kiwi Ears products. It's somewhat disappointing at this price point, but the necessities are all there: the IEMs, a 3.5mm-terminated cable (there is not an option for 4.4mm), three sets of the new Kiwi Ears Flex tips, and a small branded zipper case. The shells are solid black resin and feature a silver/pearl style inlay on the faceplate with the Kiwi Ears logo as well. The shell has a semi-custom shape and is just north of average in size. It features a flat 2-pin connection, making cable swapping a breeze, and there's also a vent hole located on the backside of the shell. The nozzle measures 5.9 mm at its widest point, where there is a lip to help hold tips in place. The length of the nozzle is about average, as well as the insertion depth. The fit is comfortable for me, and I had no issues with fatigue or pressure spots. I tried the new Flex tips and did find them comfortable, but I prefer the Penon Liqueur for a better seal since they have a slightly sticky texture. The cable is well-woven, lightweight, and doesn't tangle, but it feels a bit cheap in hand. It's fine, but I would really like a modular cable at this price, or at least a balanced option. The zipper case is small and pocketable, but it doesn't feel very sturdy and might not provide a ton of protection. Overall, I would expect this level of accessories with a set around the $50-100 range, so it is disappointing to find in a $200 package.


Sound impressions:
The KE4 features a well-balanced, well-extended U-shaped tuning with more focus on the sub-bass and the upper limits of the midrange/lower treble. It presents a very smooth listening experience with little to no objectionable peaks or valleys, but it also might be lacking in excitement for some, myself included. The note weight is neither thin nor thick, but I would prefer a little more thickness, specifically in the vocals. The tuning lends itself to a more musical over-analytical style, but there's no shortage of details on display. In fact, I hear a lot more of the rhythm and secondary instruments with the KE4 that aren't always apparent on other sets. The soundstage creates a nice orbital presentation, but I do feel that it would benefit from more width and depth as it sounds just outside the head. Overall, it's good for me, but it's not the biggest soundstage and creates a bit more of an intimate sound. The timbre is mostly spot-on and very natural, but if the vocals were more forward, I think it would sound more organic. The imaging is very accurate and a strong suit of the technicalities. The dynamics are a bit lacking and could come off as somewhat boring or safe. The separation is adequate and cohesive, with good transients and an uncongested sound that has enough room between notes without sounding disjointed. This is not an especially difficult IEM to drive, but I did find that it benefits from a bit of amplification. After trying my various dongles, I found that the KE4 pairs best with a source that is a bit brighter or neutral, as warm sources can color the sound too much. Even though a combo is available that includes the Kiwi Ears Allegro Mini, I found the KE4 pairs better with the full-sized Allegro. The Mini is capable enough, but the Allegro adds a bit of extra energy and snap to keep things interesting. Also, I received the iBasso DX180 through a separate tour at the tail end of this review, and I found that pairing to be spectacular, especially through the 4.4mm connection on high gain with the short delay fast roll-off filter. It's very early in my time with the DX180, but it sounds like a mostly neutral, perhaps slightly energetic and revealing DAP, which makes for a good match with overly warm or relaxed IEMs.


●Lows - The bass is a bit more sub-bass focused, but the mid-bass is still well represented. There is a decent amount of rumble and good extension and reverberation. The speed and tactility are impressive, and double kick drums are very easily discerned. The impact and slam are good but not super authoritative; however, for my preference, it's just about right. The bass texture is maybe a tiny bit wet but not muddy. The bass is well separated from the lower midrange, and there is no bleed to my ears. Overall, the bass is full-bodied with good extension, punch, and rumble to make it quite enjoyable. It's enough to be fun without dominating the other frequencies.

●Mids - The midrange, I think, is where the KE4 starts to lose me. On the one hand, the lower midrange has more presence and authority than I'm used to hearing, which helps to showcase some often-neglected instruments. On the other hand, the slower rise of the pinna gain means vocals aren't as forward and enjoyable as I prefer and come across as missing some life and soul. There's nothing inherently offensive or "wrong," but the middle to upper midrange being more recessed means vocals and instruments lose some of the magic qualities that other tunings bring to the table. Therefore, I think the upper midrange is a little too safe and lacks engagement. To my ear, vocals also lack a distinct weight and can feel like an afterthought, especially male vocals. Those seeking a well-separated and clear midrange, at the cost of a bit of vocal presence, can find it here in the KE4. Though personally, I wish the midrange had a little more energy and fullness, like that found in the bass region.

●Highs - The treble is quite polite but not boring. It's free of sibilance and fatigue but still quite well extended. The KE4 handles treble well for my tastes, but there is an inherent thinness and dry quality. I would argue that the highs are less safe than the mids because there is a bit of excitement here that is lacking in the midrange. Cymbals, snares, claps, and hi-hats sound just about right for my preferences. It's very natural, crisp, and clear but not overly energetic or fatiguing, although there can be a bit of harshness on "s" and "sh" sounds with some tracks. While the extension is good, I do feel like the air is a bit lacking. Those seeking more sparkle and brightness will be left wanting.



Comparison:

● Dunu DaVinci ($300) - Looking at the graph, it appears that the DaVinci may have been close to the new Meta tuning target before its rise in popularity, although the key takeaway would be the DaVinci's earlier pinna gain rise. Both IEMs have solid resin shells, fit my ears well, and caused no fatigue issues with extended use. The overall unboxing experience and accessories easily go in the DaVinci's favor. The bass responses do graph very closely, but the DaVinci's impact and slam hit harder, and it has a little more rumble. The KE4's approach from the lower to upper mids is flatter, which gives added weight and presence to the lower mids. It also has a little more treble energy and air with more crispness to notes. With the DaVinci, I don't hear any of that slight thinness in the treble that I pick up with the KE4. I can't discern a large difference in the technical performance between the two. The soundstage of the KE4 might be a bit wider. The DaVinci is a little more resolving and cohesive, with a more natural timbre and vocal presentation. This one essentially comes down to personal preference. The DaVinci is slightly warmer, analog, and more lively with a fuller sound, whereas the KE4 is a bit smoother and more relaxed with better treble extension and crispness. For a smooth, more relaxed sound, the KE4 would be a great choice. For a slightly more V-shaped, fun tuning with more vocal presence, the DaVinci is an easy recommendation, and the included accessories are far superior to the KE4's. So you have to ask yourself what tuning you might prefer and whether the better accessories are worth the extra $100. I think these two are more alike than they are different, but the DaVinci just hits almost everything perfectly for me, so there really is no debate.
My pick: DaVinci


In conclusion:
If you, the reader, will indulge me, I'd like to attempt to paint a picture of sorts. If we think of different tunings as different light sources, then maybe I can better communicate my thoughts on the KE4. Imagine one of the most common light sources that we come across in our daily lives: the fluorescent bulb. Now, not every person is bothered by fluorescent lights, just as not every IEM that I consider bright will be interpreted that way by others. But for the sake of my metaphor, this is a source that I consider to be bright, even irritating and fatiguing at times. However, it can also be very revealing, showing details that could be missed with less bright or technical sources. This would be akin one of the more traditionally tuned planars like the Letshuoer S12 or Celest Pandamon 2.0. Moving on to the next light source on the opposite spectrum—a campfire. It's relaxing, inviting, and somewhat dark but still with occasional flickers of brightness. This would be a warm, smooth, inoffensive tuning like the DaVinci, but perhaps it also comes at the cost of some excitement and detail that other light sources offer. Third, let's consider a common light source found in most homes: soft white bulbs. A tuning in this vein may be interpreted as relaxing to some or bright for others, but it would also probably be considered the most neutral by a majority of people. This would perhaps equate to something like the Hexa. Finally, that brings us to the last light source in this ill-begotten metaphor: a streetlight or street lamp. This tuning might be representative of the comfort and safety that can be found in the light against the coming of night, meaning that it might be the best option at the moment, but you wouldn't necessarily want to linger there. It's a bit dark but still offers enough light against the setting sun to see your surroundings. This, for me, is where the KE4 lies. I wouldn’t necessarily call it warm and inviting, but neither is it bright and offensive. It’s neither overly exciting nor is it boring; it’s not the most revealing nor is it lacking in detail. It’s a safe and inoffensive option, and it can sometimes come across as overly cautious or a bit lifeless depending on the source and genre of music. I would probably not recommend the KE4 for those who primarily listen to high-energy genres like hard rock, metal, and some pop, as these may lack excitement. Where the KE4 truly excels is with instrumental and orchestral arrangements because of its superb bass, extra emphasis on the lower midrange, and the well-extended, fatigue-free treble. I also enjoy the tuning with female vocalists as they are better represented than their male counterparts. Singer-songwriters such as Olivia Rodrigo, Taylor Swift, and Billie Eilish sound fantastic for the most part. If you're a bit treble-sensitive like me, the KE4 could be a great option, though you might find yourself looking for a bit more vocal emphasis. If this Meta tuning becomes the next big thing in the market, it could be a refreshing change from the constant Harman-targeted sets of the last few years. However, I personally hope that we do not see a flood of Meta-tuned IEMs in the near future, as it just feels too safe.

“New Meta” tuning for the “masses”​

The Kiwi Ears KE4 is one of the most significant IEM releases of the year. Priced under $200, this hybrid 2xDD + 2xBA IEM offers a window into a “new meta” tuning that is quickly becoming the de-facto new Target ’tuning’ to potentially replace Harman IE2019 or at least become the foundation for Harman IE2024.



Scientific Research published recently has shown this new tuning is one that everyone should at least experience and the KE4 as one of the few IEMs with this tuning and given it is currently the cheapest is a great way to experience this tuning.

Because this IEM might be the first opportunity for many to hear this “New Meta” tuning I thought I would write this review a little different from my previous reviews cross-posted on head-fi and do a little bit of a deep dive in that research I mentioned above and reverse how I do reviews showing graphs, targets and measurements before actually getting stuck into the subjective aspects like the comfort (which is excellent) and the sound quality (also excellent though as I will explain some people will definitely find it ‘boring’).

I would like to thank Kiwi Ears for providing the KE4 for the purposes of this review. If you are interested in purchasing it here is a non-affiliated link to their store: here. Alternatively, you can find it on Linsoul.
So, if you get bored talk of target curves, graphs and the latest AES research feel free to skip this next section. Because of the research just published I rewrote my review and decided it should explain why the “Tuning” target for the KE4 is very significant.

I believe this “New Meta” / JM1 / Soundguys target will become dominate over the next year and I have no doubt we will see a huge number of IEMs which will sound similar to the KE4 over the next few months.

But, I also believe a new target should not be taken as the “one true tuning” rather it should just become a good basis for understanding your own preferences / target and how it differs from industry norms, for example, with this JM1 tuning, I personally prefer slightly less bass to sound balanced to my ears and with some genres of music the more V-shaped Harman tuning is more ‘fun’.

The Significance of the “New Meta” Target​

The “New Meta” tuning represents a major shift away from the previously dominant Harman IE2019 target, which has shaped the sound of countless IEMs over the past few years. While the Harman target aimed for a “neutral” response but with both an emphasis on the bass and a significant “ear gain” / upper midrange boost, it has recently been criticized specifically for this upper midrange boost, which could be fatiguing for many listeners.

Thanks to improvements from the more accurate measurements that we get with the BK-5128 and some new research — most notably from Sean Olive himself, who just presented some updated findings this week ( which caused me to delay publishing this review ) — we now have a more accurate understanding of what “average” listeners prefer. But to fully understand what is different with the “new meta” target I need provide a little bit of background on “audio” measurements.

But you might ask how does this related to the KE4 - let me start with a graph from Crinacle (newly open to everyone) graph database here:



This graph might look a little different from others you have seen previously, but it’s showing compensated ’tilted’ measurements of a few IEMs (the Crinacle Dusk “DSP”, the Hisenior Mega5EST ), Crinacle “Project Meta” and the KE4, all compared to the JM-1 Target (with a -1 DB Tilt and a 6dB bass boost).

Why represent the measurement this way? It’s because this new research is showing a convergence between “Titled” diffuse Field measurements of Headphones and IEM with the original Speaker research that is the foundation for Audio science as far as user preferences for audio is concerned.
But before I delve a little into Speaker measurements, it is definitely worth watching Joel’s (i.e. JM-1) video on how he came up with the Target:

Speaker measurements​

Speaker Measurements thanks to the original research by Floyd Toole (and his excellent book “Sound Reproduction: The Acoustics and Psycho acoustics of Loudspeakers and Rooms” - soon to be updated with a 4th edition ) we have an extremely accurate way of understanding how a particular measured speaker will sound.

That is before its put into “your room”, but even then it gives indications of how your room will affect the sound of a given measured speaker. The research over the past few decades shows we have a general model of what makes an excellent sounding loudspeaker and one that have been proven with 1000’s of blind listening tests and published research that Floyd Toole and his colleagues (including Sean Olive) conducted initially in Canada and subsequently when they joined Harman Research.

This research basically confirms that on the majority of listeners prefer a ’neutral’ (i.e. Flat in an Anechoic chamber) sounding speaker with the majority of well recorded music. Due to the nature of a typical “Room” boosting lower frequencies over higher frequencies this “Neutral / Flat” line will always have a downward slope / tilt from the bass frequencies to the treble frequencies. I would encourage you check out both ‘Erin Audio Corner’ Speaker reviews (and Amir over at Audio Science Review) who both have expensive Klippel near field scanner and present and explain why some speakers will sound better than others.

For example, here is an example of a Genelec studio monitor measured by Amir over at ASR

The Tilt​

That “Tilt” style used in the speakers measurements are now being used by both Crinacle and the Headphones.com team to also apply to headphone and IEM graphs (via “compensation”), but if you follow lots of both Erin and Amir’s speaker reviews you will see that the exact angle of this tilt less important than that there are no big deviations from the flat download slope of this “tilt”, so there really isn’t an agreed angle. I personally would love to see a “tilt” adjustment (like Bass and Treble adjustments) in future audio products.

So again referencing those initial measurements from Crinacle’s BK-5128 - this time I have just left the tilt but removed the extra bass boost (you will see the reason why in minute) and I just left the KE4 and Crinacle “Project Meta” (which isn’t released as I write this review) as both are astonishing similar:


Note: if this was a “hyper critical” speaker review 3 aspects of the measurements above might be of concern. The bass boost, the upper treble boost and possible that little dip between 1K-3K. That latter area is often manipulated to provide a slightly wider soundstage and if you compare with the Genelec Speaker graph you will see it shares that same feature for similar reasons (as do most ‘soundstage’ headphones like HD800 or most Hifiman Headphones.

But the Kiwi Ears KE4, the Project Meta, the Hisenior Mega5EST and other “Meta” tuned IEMs all have this same Bass and upper treble Boost, so to cover this let me introduce another “Target” reference that I mentioned earlier, the “Soundguys” Target. Independently of the JM-1 target development, Soundguys developed their own target which happens to be almost exactly the same as JM-1 (or it is at least JM-1 with a Bass Boost hence the reason I removed the bass boost from the previous graph).

Soundguys Target​

Let’s have a quick look at JM1 (with a bass Boost) and Soundguys Targets uncompensated:


Note: Thanks to Markanini over at ASR for this comparison graph.

So you can see the Soundguys has that same bass boost that these new IEM Meta tuned all share and even have a slightly boosted upper treble which again appears within the KE4 measurements. Again here is another comparison this time with the now typical preference bounds and adding the Dunu DaVinci to the graph for further comparison:



Note: pure “neutral” JM-1 would effectively be line accross the middle of these preference bounds

The latest Scientific research​

Up to about a week ago there was very little official research published about these new targets but then Sean Olive released an AES paper showing the latest blind testing he has carried out with a small team of trained listeners within Harman comparing a few different targets. He presented this research paper at a AES conference this week.

This research is freely available here

Note: While this research is very interesting (and important) for the future of IEM targets and I thought it was useful for this section of the KE4 review, I would say the number of people and even the number of test tracks used was quite limited, so I would expect expanded research over the coming months.

So, here are the 5 targets compared in the research:


So, crucially he used this Soundguys target in this testing (hence why I added this section - effectively JM1 with a bass and upper treble boost), and it was found to be in a statistical tie with the latest Harman Target (technically slightly beating the Harman IE2019):

Considering this research was done with “trained listeners” within Harman who would be well-used to the Harman IE2019 sound I think it’s a very significant change in “researched” preferences.

But probably the most interesting aspect was that these very different target curves were preferred by the same group of people, because this means as many people in this hobby already know, it worthwhile having a few great sounding IEM’s with different tunings, there is not just “one true target curve”.

What does it mean for the KE4?​

So what does this mean for the KE4? It mostly means up to now the hype surrounding the IEM’s like the HiSenior Mega5EST and the Crinacle Dusk DSP is totally justified, but given the Kiwi Ear KE4 is 1/2 the price of those IEMs and is arguable more comfortable, it is the reason I believe this is one of the most significant IEM releases this year.

So, if you are still reading, I think it’s finally time to get into the subjective aspect of the KE4.

So first lets see what you get in the box.

Unboxing and Build Quality​

The unboxing experience of the Kiwi Ears KE4 is fairly straightforward but solid.

The box is minimalist and doesn’t really match up to other $200 IEM unboxing experiences, removing the outside sleeve reveals the box:

Underneath you’ll find the case, and inside you the cable, a small selection of eartips and some replacement caps:

Overall, I would say it’s a basic accessor offering for an IEM in this price range.

The IEM​

But the IEM itself is gorgeous with a lovely shell and an excellent opinionated shape:



The nozzle is medium-sized on the size and nicely angled (at least for my ears) so this greatly helps with the comfort and fit:




Here are some photo comparisons with a few of my other IEMs, left to right.

FiiO FH19, Truthear Zero Red, Orchestra Lite, KE4, Meze Alba, FiiO FD15.

The Eartips​

The eartips provided have a slightly unusual design:


I would have preferred more eartips options to suit different shaped ears, but they are very comfortable and I had no problems with them falling out.

While I did initial use these eartips for a few days, I ultimately switch to my favourite Dunu eartips, though I did my measurements with the supplied eartips.

The Cable​

The Cable is merely ok for this price range, I found it a little thin, and it got way too easily tangled:


I would suggest swapping the cable for a higher quality one, for example Kiwi Ears Orchestra Lite cable is much better.

But it’s connectors are built well enough:



And has a nice shape to wrap around your ears:

Sound Impressions​

So, when I first wrote this review I focused mainly on these sound impressions, but there are many other reviews with sound impressions but especially because this new published research I rewrote most of this review. But hopefully below you will see get an idea of how the KE4 sounds for me and the pros and cons of having a “New Meta” tuned IEM.

If I was to summarise how it sounds it would be “silky smooth neutrality with a bass boost and a ‘safe’ recessed treble”.

Bass​

The bass on the KE4 is well-controlled, providing a satisfying thump without overwhelming the rest of the spectrum. For the most part, the bass feels balanced, but there is a slight elevation in the mid-bass that may be a bit noticeable for some listeners. In tracks like Billie Eilish’s “Bad Guy”, the bass felt just a touch overpowering hence my preference so a slight bass reduction. However, on 99% of the tracks I tried including classic bass-heavy test tracks like Portishead’s “Roads” and Massive Attack’s “Angel”, the KE4 delivers tight, punchy lows that are impressive for the price range.

So, for my personal taste, I might drop the bass by 1dB for a more neutral tilt.

Mids​

The midrange is where the KE4 truly shines. The lower mids seamlessly blend with the bass, creating a smooth and engaging sound without ever feeling recessed or overshadowed. Vocals, especially female vocals, come across naturally, without the dry or overly polished texture found in some other IEMs tuned for neutrality. Tracks like Tracy Chapman’s “Fast Car” and Elvis Costello’s “Baby Plays Around” showcase the midrange beautifully, with vocals sounding both intimate and expansive.

Treble​

The treble on the KE4 is generally well-behaved, though it does err on the safe side.
While it avoids the harshness or brightness that can plague some IEMs, it also lacks a bit of sparkle or air. Especially for listeners coming from a “Harman” or V-Shaped tuning will find this treble too “safe”.
But on traditional challenging tracks like Michael Jackson’s “Billie Jean” and The Beatles’ “She Said She Said (2022 Mix)”, the treble performed admirably, never becoming fatiguing or shrill.

However, for those seeking that extra bit of excitement in the high end, the KE4 will feel a little too restrained.

Soundstage and Imaging​

The soundstage of the KE4 is not the widest you’ll find, but it’s good for this price. What it lacks in width, it makes up for in imaging. Instruments are placed with precision, and layering is excellent. On tracks like Iron & Wine’s “Sweet Talk”, the imaging really stands out, with each instrument and vocal line distinct yet cohesive.

I believe the benefits of this tuning over a Harman tuning are really that mid-range clarity which help emphasis the precise imaging, this is why you need at least one “new meta” tuned IEM in your collection.

Specifications and Measurements​

Frequency Response​

All these measurements (unlike the ones I presented earlier) are done with my KB501X soft ear pinna with a 711 clone coupler.



So you can see a similar shape to my KE4 measurements (though Crinacle measurements that I presented earlier are obviously more accurate using his BK-5128).

Note: The JM-1 target on my measurement Database is neutral without that bass boost - I will be updating the Database soon with preference bounds around JM-1 and other niceities.

Distortion​

The KE4 has very good low distortion when playing over 90dB always under the audible limits (of roughly 40dB):

Measurements Comparisons​

I thought it might be interesting to compare the KE4 with some other similar priced IEMs that I have reviewed in the past few months (and the Meze Alba - review coming in a few days):



Since this graph comparison uses Harman (as the other IEMs would normally be compared to Harman) I thought I would highlight the key differences with the KE4 from these other (all excellent) IEMs:

1. Highlights the 2 areas where JM-1 / Soundguys target is different in the midrange between a typical Harman (like the Meze Alba in ‘Red’)
2. The KE4 (and other similar tuned JM1) have a ‘Harman like’ subbass - though my specific model may be similar to one version of the KE4 that the headphones.com team received and mentioned in their review that had slightly extra bass:
   
   
3. The KE4 has that specific upper treble boost (similar to the Soundguys target)

So, you might be wondering which of these IEMs which would I prefer the most? It would be either the KE4 with a slight bass reduction or the FiiO FD15 (which has closer to JM1 Neutral bass but does have a more Harman midrange so maybe EQ it down to JM1 range). But, and the research confirms this, I would also want to have in my bag, an excellently tuned Harman IE2019 IEM like the rather excellent Meze Alba.

Rating​

I am giving the Kiwi Ears KE4 a very pragmatic 5-star rating. While I have a few quibbles about accessories and especially the cable. The IEM itself is extremely comfortable and the tuning is mostly excellent, but it won’t be the most exciting ‘sounding’ IEM to be released this year. But it does allow everyone to appreciate this “new meta” ‘Neutral with a bass boost’ tuning and for that reason, it is an easy 5-star rating.

I personally would tweak the bass slightly for my personal taste (at least with the model I have been listening too), these are minor issues that do not detract from the KE4’s overall excellence.

Conclusion​

So, Kiwi Ears has done something special here, providing a relatively cheap option for listeners who want to experience what this cutting edge tuning is all about without paying the high costs associated with 4 or 5 flagship models that have up to this point been the only way to officially hear this tuning.

If you’re looking to expand your collection with something tuned for modern preferences, the KE4 should be at the top of your list

Kiwi Ears KE4 - Metaphorically, Meta Is The New Black​

Disclaimer​

• The reviewed IEM is a sponsored unit by Kiwi Ears. Nevertheless, all opinions are original ideas, there is zero influence from any 3rd party or external opinions.
• No EQ or filter presets were used during the entire review period.
• Sound evaluation are kept neutral and does not include 3rd party accessories (ie; eartips, cable, reversible/irreversible mods)

Click to expand...

Introduction​

When I first listened to the Kiwi Ears KE4, I’ll admit—I was a bit underwhelmed. It didn’t hit me with the impact I was expecting, and for a moment, I thought it might not be for me. But something interesting happened over the next few days. As I spent more time with it, the KE4 started to grow on me. It’s one of those IEMs that doesn’t show its hand right away. Instead, it slowly reveals its strengths, and before I knew it, I found myself reaching for it more often than my usual favorites.

What stands out about the KE4 is its clever tuning. It doesn’t need to grab your attention with aggressive or showy sound. Instead, it offers a beautifully balanced, neutral presentation with just the right amount of sub-bass boost. It’s like a finely brewed cup of coffee—not too strong, not too weak, but perfectly satisfying. That subtle sub-bass adds warmth and depth without overpowering the mids or highs, creating a cohesive sound that’s easy to listen to for extended periods.

The KE4 excels in comfort, not just in how it fits physically but in its sonic presentation. There’s a sense of ease in how it delivers sound. It’s safe, yes, but in the best way possible—like a favorite pair of well-worn shoes that you just keep coming back to because they’re dependable and always feel right. In fact, I’ve found myself reaching for the KE4 more often than I anticipated, even replacing some of my usual daily drivers.

This IEM doesn’t need to shout to get its point across. It’s confident in its balance, offering a sound that’s smooth, detailed, and inviting. The more I use it, the more I appreciate its restraint and how it manages to strike that elusive balance between neutrality and warmth. It’s the kind of tuning that sneaks up on you, making the KE4 a set that quietly but consistently earns its place in my rotation.

Whats in the box? a short unboxing video of Kiwi Ear KE4 and the Allegro mini.






The KE4 is a great example of a "Goldilocks" IEM, walking the fine line between neutrality and warmth without falling into the trap of sounding dry or overly clinical. It’s refined, delivering a smooth and relaxed listening experience that won’t overwhelm your senses. There’s a sense of ease here; it’s not trying to wow you with fireworks or thundering bass. Instead, it offers a balanced soundscape that keeps you engaged without fatigue and i do believe this what "Meta" tuning is about..

Now, if you’re after an energetic,bright and super fast decay and attack this might not be your go-to set But that’s not its game. It’s designed for long, immersive sessions, where the subtleties of your favorite tracks shine through. In a crowded mid-tier IEM market, the KE4 confidently carves out its space by simply being comfortable in its own.

Tonal Characteristics:

Tonally, the KE4 lands squarely in the neutral camp with a tasteful sub-bass lift. It’s an IEM that plays it cool. The overall tuning is smooth and laid-back, devoid of any harsh peaks or dips that could make prolonged listening fatiguing. There is no jagged edges or sibilance snapping you out of the moment, it prioritizes musicality and relaxation over sheer thrill.

Bass:

The bass on the KE4 is a textbook example of moderation—no jaw-rattling rumbles here, just a gentle sub-bass presence that gives the sound a pleasing foundation. It’s not a basshead’s dream by any means, but it still has enough punch to keep things interesting. The bass is relatively quick and controlled, though there is a hint of bleeding on the mid-bass that seeps into the lower mids, adding warmth and a thicker overall presentation. Texturing, however, is somewhat blunted, and while it doesn’t impact the listening experience dramatically, it does lack detail that bass aficionados might crave but also make up for it super buttery smoothness.

Midrange:

They're lush, neutral, and subtly warmed by the bass, creating a rich, inviting tone that brings both vocals and instruments to life. The slight warmth adds a pleasing fullness without sounding overly thick, giving the mids a euphonic, natural quality that feels effortless on the ears. The upper mids are handled with finesse, striking a well-calibrated balance—there’s energy, but it’s not in-your-face, and there's detail without pushing the mids too far forward. Female vocals, in particular, sound smooth and organic, making the KE4 a standout choice for those who cherish a laid-back yet detailed midrange. It's the kind of presentation that allows the music to flow naturally, capturing the heart of the performance without sacrificing comfort, even over long listening sessions. Midrange lovers, especially those seeking a smoother, less aggressive tuning, will likely find a lot to enjoy here, reminds me of the natural smoothnees of Tangzu Xuan NV.

Treble:

The treble on the KE4 is tailored for listeners who value a smooth, fatigue-free experience. It's a laid-back presentation, carefully tuned to avoid harshness and sibilance that can make long listening sessions tiring. Instead of sharp spikes or piercing highs, the KE4 opts for a more subdued, gentle treble, striking a balance between clarity and comfort. While it does roll off softly, it manages to retain enough detail to keep things engaging without pushing for extreme brightness or sparkle.

Rather than aiming for a highly analytical or ultra-revealing treble, the KE4 presents a softer, more rounded sound. This might mean micro-details are slightly less prominent compared to more aggressive or treble-forward IEMs, but they’re still present—you can hear those intricate details, just in a more relaxed manner. High hats, cymbals, and other high-frequency instruments don’t have the sharp, crisp attack that you’d find in more clinical or detail-focused sets, but they remain natural and well-placed within the mix.

This tuning gives the KE4 a more relaxed character, making it ideal for listeners who prefer a smoother sound signature over the sharper precision of brighter IEMs. For treble-heads or those looking for a more revealing upper-end, the KE4 may come off as a bit too polite. But for those who prioritize comfort and a non-fatiguing listening experience, its treble delivers a wonderfully balanced response.

tecnicalities:

When paired with the right amplifier, the KE4's soundstage opens up beautifully, offering a sense of space that feels wider than expected. The instruments have room to stretch out, and the whole experience feels more immersive. Imaging is also impressive; while it might not rival the most analytical sets, it still lets you pick out individual instruments with a satisfying level of clarity. It's like the KE4 whispers, rather than shouts, the placement of each element, giving you a sense of precision without being overly clinical.

However, the KE4 doesn’t pretend to be the most resolving IEM in its class. The finer micro-details may sometimes feel a bit veiled, but that’s part of its charm. It’s forgiving, smoothing over imperfections and presenting the music in a way that’s easy on the ears. If you’re the type who enjoys dissecting your favorite tracks down to the tiniest elements, the KE4 might seem a bit too gentle. But if you’re looking for something to simply enjoy music without overthinking every note, the KE4 absolutely delivers.

Final Thoughts:

The Kiwi Ears KE4 brings a refreshing sense of warmth and ease to the table, offering a listening experience that feels inviting rather than demanding. It’s the kind of IEM that you can comfortably reach for time and time again, knowing it will deliver smooth, musical sound without fatigue. At $199, it provides a well-rounded mix of focused sub-bass, lush mids, and soft treble—perfect for those who enjoy a more laid-back, yet engaging presentation.

It may not be the go-to for those chasing intense dynamics or ultra-sharp detail, but that’s not what the KE4 is about. It’s for the listener who wants to settle in for the long haul, enjoying a balanced sound that strikes the right note between comfort and clarity. The KE4 doesn’t try to be flashy; instead, it offers a genuinely enjoyable experience that lets the music take center stage.

In short, the KE4 is ideal for anyone who values smooth, musical warmth with just enough detail to keep things interesting. It’s a comforting, reliable option that’s easy to love—and for that, it’s definitely worth considering.

Kiwi Ears KE4 Product Link : https://www.linsoul.com/products/kiwi-ears-ke4

Kiwi Ears KE4
I was contacted by Kaitlyn Wu from Linsoul and invited to test and review the new Kiwi Ears KE4 IEMs.

Product links:
Linsoul website: https://www.linsoul.com/
Linsoul Aliexpress Store: https://ddaudio.aliexpress.com/store/2894006
Linsoul USA Amazon Store link: https://www.amazon.com/s?me=A267P2DT104U3C&marketplaceID=ATVPDKIKX0DER

Kiwi Ears is a company specialising in crafting superior audio products, particularly in-ear monitors and earphones. Their dedication lies in presenting natural and balanced sound, prioritising efficient performance and cost-effectiveness.

The KE4, their latest product, is a hybrid IEM (2DD + 2BA) which has been tuned to a modified version of the Harman profile, known as the "new meta". It employs two 10mm DDs in an isobaric configuration and two BAs covering the midrange and treble. It retails for $199.

The Packaging
The KE4 comes in a chunky rectangular box with a card sleeve featuring the IEMs prominently displayed along with the product name and the legend: "Live the music". Removing the sleeve reveals a plain black box with a metallic Kiwi Ears logo, inside which you will find the IEMs set in a removable card cut-out. Under this the zipped carry case is stored, containing the 2-pin cable and the silicone eartips.
For an IEM retailing for around $200 the packaging is perhaps rather basic. It includes:

● Kiwi Ears KE4 IEMs
● 2-pin silver-plated copper cable
● Three pairs "Flex" white silicone ear tips
● Zipped carrying case
● Documentation

Design and Build
The KE4 is well-constructed in an opaque medical grade black resin with a metallic/pearl effect faceplate bearing the Kiwi Ears logo. The 2-pin sockets are recessed and accept a standard 2-pin connector. There is a small circular vent with a mesh on the back of the earpiece and there is channel identification on the underside. The earpieces are fairly light in weight.

The KE4 uses two 10mm dynamic drivers for the bass frequencies, arranged in an isobaric configuration. The midrange is handled by a custom RAB 32257 vented balanced armature and the treble is covered by a Knowles RAD 33518 BA. There is a three-way passive crossover system and a network of three sound tubes channeling the sound.

The 2-pin 4-core cable is supple, handles well and appears to be of high quality. It is constructed of silver-plated OFC copper. The 3 5mm plug is finished in a chrome effect and there is a matching Y- split and ring-shaped chin slider.

Fit and Isolation
The KE4 proved to be very comfortable in use. The supplied silicone tips have a mesh-like feature in the opening and were soft and pliable with good grip. With the medium size installed, the earpieces fitted securely and snugly in my ears with good isolation. The stock cable also felt secure and comfortable.

Sound Impressions
The IEMs were tested with a variety of sources including three different DAPs, a smartphone, digital radio and a Penon OS133 USB-C dongle. Although adequate volume was obtained from all the sources, I did also include an amplifier and the Little Bear B4-X was employed for this purpose. A burn-in period of 100 hours was used to settle down the components and the earphones were auditioned with music from a wide variety of genres. The majority of the review was carried out with a Hidizs AP80 Pro X DAP with the Penon OS133 USB-C dongle which furnished the IEMs with adequate power.

Tonality
The immediate impression was of an unforced delivery with a natural timbre, a well-balanced profile and no particular frequency band emphasised above the others. This "new meta" approach was certainly an improvement on the regular Harman-type curve with none of the mid-bass emphasis, recessed mids and rolled-off treble which I find characteristic of that profile. There was a deep and solid bass, an exceptionally clear and open midrange and an airy and well extended treble. This resulted in a very musical presentation with a seamless transition between the different drivers and a consistency of tonality across the frequency range. The soundstage was expansive with excellent imaging and layering.

Bass
The KE4's bass was deep, resonant and speedy. Sub bass displayed good rumble and definition and the timbre was natural. Mid bass possessed an entertaining kick with snappy rhythmic attack and it did not bleed into the midrange. The texture was nicely judged and the overall feel was very natural.

The score to Stravinsky's ballet "The Firebird" is a colourful work for large orchestra with prominent use of percussion. The Finale begins in a serene fashion with a gentle theme on strings and woodwind. Soon it becomes more rhytmic and forceful, announced by timpani strikes and staccato brass figurations. A powerful strike of the bass drum follows, leafing to a climactic finish. In the version by the Minnesota Orchestra under Eiji Oue, the bass drum displayed extraordinary power and slam with a long resonant decay. The rebound of the skin and the airy ambience and sustain were beautifully handled by the KE4, proving the success of the isobaric twin driver set-up.

"Evensong" is the title track from the ambient electronic album by Meg Bowles. Smooth airy synth patches glide and mutate above a bass drone overlaid with a semi-melodic series of chord progressions. As the piece develops, a deep sub bass element is added to the layers and it came over very convincingly on the KE4. There was an impressive sense of potency and depth which enhanced the somewhat spooky atmosphere of the piece and formed a perfect foundation. The texture produced here was exactly what the piece demanded.

"Cluster One" is the opening track on "The Division Bell" by Pink Floyd. This instrumental piece begins with the sound of a crackling wood fire accompanied by atmospheric electronic effects. A chordal drone joins in followed by a minimalist minor key theme from Dave Gilmour's guitar. Rick Wright's piano enters into a kind of antiphonal conversation with the guitar and the two instruments intertwine. This is then supported by deep rhythmic elements from Nick Mason's drums bringing the whole piece together. The depth and kick from the percussion reproduced by the KE4 was extremely impressive with good speed and impact.

Midrange
The KE4 excelled in the midrange. It was open and transparent with a natural timbre and copious detail. Vocals were reproduced wonderfully well with fine detail such as lip sounds and reverb adding to the realism. There was a consistency of tonality throughout the range with a well judged pinna gain resulting in a relaxing yet engaging delivery.

Pluto Shervington's "Your Honour" is an amusing tale of a wrongly-accused person who was "inside the closet" when the crime was committed. Beautifully recorded and produced and set to an infectious reggae beat with a fast-paced backing, the KE4 made the most of it with the lead vocal clearly defined and supported by snappy rhythms, incisive percussion and punchy bass guitar. The openness of the reproduction conveyed the humour of the story in a very entertaining fashion with the vocal nicely projected above the accompaniment.

Cello and piano are testing instruments in determining timbre. Reynaldo Hahn's "L'heure Exquise" is a wonderful concentrated piece of emotional writing. In the recording by Mischa Maisky and Daria Hovora, the KE4 regaled the listener with a natural tonality and clean transient attack. The decay and sustain of the instruments, combined with the sensitive playing, brought the musicians direct to my ears with a real sense of presence whilst at the same time communicating the beauty of the music.

Brazilian violinist Marcus Viana has recorded 55 albums in several genres such Progressive Rock, World Music, New Age, Classical and Instrumental. "O fim das coisas" from his album "Trilhas e Temas" (Tracks and Themes) features his trademark violin solos supported by a lush electronic accompaniment. Opening with a romantic string arrangement, a synth guitar voice states the theme, underpinned by bass and further string layers. Soon Viana's violin joins in and echoes the lead melody. The intertwining of the two voices was wonderfully captured by the KE4 with the natural timbre of the violin highlighting the soloist and communicating the emotion of the piece. At the conclusion the guitar voice plays a falling arpeggio and the piece subsides into silence.

Treble
The KE4 surpassed my expectations with superb extension, an authentic timbre and a smooth delivery. Detail retrieval was top class with an attractive delicacy and the transition from the midrange was seamless. The pace and timing evident in the bass and midrange was also present here, endowing the high frequencies with an addictive urgency and there was an atmosperic and airy quality throughout the range.

"Lady d'Arbanville" is a classic track by Cat Stevens. The acoustic guitar introduction came over precisely with a notable immediacy, endowing the piece with a live feel. Cat Stevens's vocal was perfectly positioned in the centre with his diction clear and the character of his voice clearly defined. During the instrumental break, the steel strings of the acoustic guitar were clearly delineated with a crisp leading edge which was testament to the fine treble extension and the fine detail on offer allowed the playing of the instrument to be appreciated.

Steven Halpern and Dallas Smith collaborated on the album “Natural Light” featuring Halpern’s gentle keyboards and Smith’s intricate Lyricon solos. The title track is characteristic of the album's style and the KE4, with its superb extension and detail ensured that even the highest notes remained audible whilst remaining clean and precise in nature. The balance between the keyboards and Lyricon was well judged and the spiralling and reverberating solos set against the synthesised bass produced a magical hypnotic effect drawing the listener into the music. The Knowles 33518 BA really showed its class here with the ethereal quality of the high frequencies extending beyond audibility.

Ernest Moeran’s Symphony in G minor is a superb example of 1930s British music, replete with syncopated rhythms and lyrical interludes. The The third movement is a bright and playful scherzo with a prominent woodwind presence. The KE4 rose to the occasion presenting a light and spacious picture with a sprightly dance-like quality and Sir Adrian Boult’s superb interpretation in a sumptuous Lyrita recording with the LPO came to life with lively pizzicato strings, bright brass and crisp percussion. The KE4's treble was airy and extended, being perfectly suited to the score and adding to the atmosphere of the recording venue.

Soundstage and Imaging
The KE4's wide frequency response, extended treble and deep textured bass produced an attractive and expansive soundstage. Layering and separation were on point and stereo imaging was of a high standard allowing the positioning of instruments to be clearly defined. Studio ambience, due to the fine bass extension, added atmosphere to the reproduction especially in classical music.

"Judex" from "Mors et Vita" by Gounod is a beautiful melodic piece for full orchestra. In the version by the Halle Orchestra under Maurice Handford, the KE4 laid out the players in a most convincing fashion with the positioning of the various sections true to life. This was considerably helped by the superb recording produced by Mike Clements ( also known as Mr Bear) with the prominent brass fanfares, bass drum and percussion and the lyrical string melody combining to produce an authentic picture of the orchestra and give a real sense of "being there". The main theme, spanning the octaves, was sensitively portrayed and the whole piece gelled together very well.

Al Stewart's seminal album "The Year of the Cat" is an all-ime classic with a wonderful production by Alan Parsons (producer of Pink Floyd's "Dark Side of the Moon"). "On the Border" begins with a fast-paced bass riff accompanied by percussion. Acoustic guitar comes in and then Stewart's characterful vocals are added. On the KE4 the various elements filled the stage in a very impressive way with each part clear and well defined and always in balance with each other. Peter White's wonderful guitar solo in the bridge was nicely highlighted with a good sense of ambience and the track was propelled along with excellent pace and timing.

Davol is an electronic music artist hailing from America's Pacific Northwest. His first album, "Mystic Waters" was released in 1989 on Silver Wave Records. The title track features a guitar-like synth lead, supported by lush electronic soundscapes, percussion and electronic effects. The KE4 presented the stately main theme very clearly with the lead voice positioned high in the image whilst swirling synth strings moved around the stage. The tonalities of the various synth voices were nicely differentiated and contrasted, resulting in a very atmospheric presentation with a good sense of space and fine detail.

Comparisons
TRI Starsea
The Starsea is a hybrid IEM employing a 10mm LCP DD for the bass, a Knowles 29869 BA for the midrange and a TRI Hi A custom BA for the high frequencies. There are two tuning switches giving four different tuning profiles.

For the purposes of this review, the "Amazing Bass" setting was chosen. In this mode, the profile was mildly V-shaped with a bass a little north of neutral, an open and detailed midrange and an extended and detailed treble. In someways it is similar to the KE4 but has a cooler tonality with a much reduced bass presence.

The KE4 has a superior bass and a better overall balance, is warmer and more amenable to different genres, whereas the Starsea lacks the punch and presence for most modern styles. The Starsea matches the KE4 in soundstage and treble extension and has a comparable midrange but because of its versatility, the KE4 is preferable.

TRN TA2
The TA2 is another hybrid, 1DD + 2BA. The bass driver is a 10mm carbon nanotube type (CNT) and the midrange and treble are handled by two Knowles 33518 drivers, placed in the nozzle. The shell is full metal and is vented.

The TA2 is tuned more conservatively with a warm/neutral tonality and the treble is less extended than either the KE4 or Starsea. The midrange is thicker with a little less detail but is very musical and relaxing. There are no harsh peaks in the response and the bass is also full and mellow. This relaxing profile allows for extended listening but does miss out in terms of resolution and detail. The KE4 manages to be resolving and detailed while still delivering a musical and entertaining profile. Once more, the KE4 is the preferred choice.

Tin Hifi T3
Although now a little long in the tooth, the Tin T3 still has much to offer. It is a dual hybrid (10mm PU/PEK DD + Knowles 33518 BA) and is a bullet- shaped IEM with a full metal shell and MMCX connection. The stock cable is of very high quality.

In terms of sound, the T3 is closer to the KE4 than the Starsea or TA2 models described above. The bass is sub-bass focused with a more neutral mid bass but it still possesses a "kick" in that region. Bass texture is very good, as is speed and resolution. The midrange is opening detailed with good separation and imaging and the 33518 BA is similarly tuned to that in the KE4. Though it was released in 2019 it still holds its own in terms of sound quality. Where the KE4 improves on it is in the bass, where the isobaric set-up delivers more depth and speed and in the treble which is more detailed and delicate. Of course, the KE4 is around four times the price of the T3 but still represents excellent value.

Conclusion
When an IEM comes along which matches one's preferred tuning it is difficult to find anything negative to balance out the positive comments. Personal bias is a powerful thing. If I were to specify the qualities it should have to suit my preferences, it would have deep, solid and powerful sub bass, a punchy mid bass which does not bleed, transparent and detailed mids with excellent layering and vocal projection. There would be a moderate pinna gain and a smooth, airy and extended treble and the soundstage would be spacious with a transient attack which is speedy and precise. The KE4 is such an IEM.

The accessories are a little disappointing at this price, as others at this level include a modular cable and a richer experience, and perhaps the shell could have been all-metal, but overall the KE4 is a fine product.

The Knowles 33518 treble driver was very well tuned in the KE4. Being familiar with it in previous IEMs such as the Tin Hifi T3 and TRN TA2, I was expecting a good performance and I was not disappointed.

It is likely that some may find the tuning of the KE4 a little bit "safe" and perhaps wish for a little more excitement, but that would involve a degree of colouration which would, I feel, unbalance the presentation. Sound quality, of course, is the most important factor and the KE4's delivery is perhaps the definition of balanced tuning, as intended with the "new meta" approach, and as such it must be considered a success and is highly recommended.

TL;DR: A neutral, balanced, detailed Explorer

Overview/History
Hi all.

Here again with another review of the Kiwi Ears KE4. What's crazy is that this is actually my 20th review. I have no idea how/why I decided to get started on this side of the hobby but I'm extremely glad I did. I was content with just listening to some high end headphones and browsing/following threads here and there but it's been very fun testing out various equipment and getting to figure out my preferred tonal balance.

Kiwi Ears has been around for a bit and been generally known to have 'unique' tuned sets. Some have worked out great for people, some have not. I will actually preface this by saying that I've listened to the Kiwi Ears Melody and the Cadenza previously; I liked the Cadenza well enough but the Melody was a bit harsh to me on the treble side.



Still, Kiwi Ears products are generally well priced and their dac/amps have a lot of flair to them.

Enter the Kiwi Ears KE4 which is their newest mid-fi priced IEM at $200.



From Linsoul's website:
The KE4 starts fresh from the ground up, featuring a 2 Dynamic Driver (2DD) isobaric sub-woofer system, combined with 2 Balanced Armature (2BA) full-range and tweeter speakers. The 2 Kiwi Ears custom 10mm dynamic driver focuses on sub-bass impact and slam, highlighting kick drum and bass guitar presence. A RAB 32257 BA driver, which has been customized with enhanced ventilation, ensures a seamless integration of the bass with the midrange, while providing lush and textured vocals and instruments. An American-made Knowles RAD 33518 BA tweeter delivers pristine and natural-sounding treble with excellent upper frequency extension for an airy sound.

Specifications so you don't have to look yourself:

• Driver: 2 Balanced Armatures, 2 Dynamic Drivers, 1 Knowles RAD-33518, 1 Customized RAB-32257
• Sensitivity: 102dB (±1dB)
• Crossover: 3-Way Crossover Network
• Sound Tubes: 3 Independent Sound Tubes (for high, mid, and low frequencies)
• Driver Details: 1 Ultra-High Frequency Driver, 1 Mid-High Frequency Driver, 2 Low Frequency Drivers
• Impedance: 28 ohm

Disclaimers: I would like to thank Kaitlyn from Linsoul for this review sample that was received in exchange for my honest opinion. I was not given any directions or instructions so the statements below are all my genuine take.

You can pick up the Kiwi Ears KE4 at these below non-affiliate links:
Linsoul website: https://www.linsoul.com/
Linsoul Aliexpress Store: https://ddaudio.aliexpress.com/store/2894006
Linsoul USA Amazon Store link: https://www.amazon.com/s?me=A267P2DT104U3C&marketplaceID=ATVPDKIKX0DER

Build Quality, Comfort and Accessories
Photo dump time!









The KE4 is a relatively comfortable sized IEM with a Nozzle Lip measurement of 5.9. I actually really like the almost understated/simple look that Kiwi Ears generally rolls with.







The KE4 comes with a carrying case, the Kiwi Ears Flex tips and a decent cable.



Tip Rolling
So, as someone who already uses the Kiwi Ears Flex tips, this is actually going to be pretty easy. Again, as opposed to going through every single set of tips, I'll do two additional ones.



Final Type E - Clear/Red: I love the Final Type E on the KE4. It helps bring some additional sub-bass feel while the treble still remains largely intact. Great combination, honestly.
Kiwi Ears Flex: A further enhancement to the bass and to make the KE4 more engaging, the Flex tend to subdue the treble extension by just a bit but it helps give it a warmer color. Of course this combination works but not everyone likes the Flex tips. I do for the most part so I don't have any negative things to say about them.
Radius Deep Mount: Just like the Type E Clear/Red, the Radius Deep Mount do something very fun with the bass texture/boost while still being intact on the mids/treble. If you have the Deep Mount, they're great in this case.

Cable
I think the stock cable is actually not that great.



Hardware on the cable is heavier than the entire cable itself. It's a bit thin as well but, overall, not the worst I've ever used. Not great for $200, though, but it does seem like most of the effort went into the IEM itself.

Sound
So, how do they sound?



This is a very nicely tuned set. It's extremely inoffensive, it's extremely neutral/balanced sounding due to the implementation of drivers and the general attack/decay, and it works especially well at higher volume listening. There's a lot to like overall while it may not win a lot of awards, it's a very solid entry into the Kiwi Ears line up.

Gear Tested On: Primarily streamed music via either dedicated Streamer, Laptop or Phone
Phone chain: Pixel 8 Pro -> Abigail Pro
Phone chain: Pixel 8 Pro -> Shanling Onyx XI1
Streamed Music Chain Workstation: Laptop -> JDS Labs Element 3 MK2 (Boosted)
Streamed Music chain: WiiM Mini -> JDS Labs Atom DAC+ -> JDS Labs OL Switcher -> Geshelli Labs Archel 3 Pro

*My Audio Preference and Score Disclaimer*: To preface my breakdown, here's my sound preference. I tend to prefer warmer sound. I enjoy good sub-bass extension with enough mid-bass to feel the music. I prefer more fuller sounding mids to match my library. My preference is for smooth treble extension; while I'm not treble sensitive, I'd probably lean more towards 'safer' treble tuning for longer listening. I also tend to listen at either medium to louder listening volumes (reasonably loud).

In addition, all scores listed below are typically (unless otherwise stated) rated/scored as it relates to it's peers in the same price group.

Lows/Bass: The bass on the KE4 graphs like this would be a bassy boy but, overall, the implementation of the drivers actually make this set sound more neutral with just a tad bit more of a sub-bass boost.

The bass, overall, is very fast with the attack but the decay also has that quick characteristic which prevents the bass from sounding fuller. It's still very deep sounding on the sub-bass and very detailed/textured but there's a missing oomph on the mid-bass which was tuned to reduce bleed.

Overall, it's not -bad- but don't let the graphs fool you into thinking that this is a bassy set. It's fast, punchy, deep sounding but notes go very quickly in favor of more of a detailed neutral sound.



Bass Score: 7.5/10 - TL;DR: Sub-bass is well extended. Mid-bass could use a bit more punch. Detailed but the decay is too fast for my tastes

Mids: Keeping with the overall trend, the KE4's mid-range is very detailed and works well for certain aspects of my library.

Both female vocals as well as instruments shine the most. There's a good rise to the upper mids which adds a good amount of air and keeps female vocals sounding very natural. Instruments are clean in their replay. The KE4 is very technical in this aspect.

My primary issue is that the male vocals can come off as a bit thin and there's an overall lack of warmth or full sounding note weight. Things can come off a bit dry which can work especially well with guitar heavy tracks but it won't have the musical tone that something like the Explorer has.

Mids Score: 8/10 - TL;DR: Great for detailed instruments and female vocals, very thin male vocals and lacks warmth. Comes off a bit dry. Would be great for some libraries (rock oriented) but may not be ideal for others.

Treble: The treble extension is very good albeit safe. I don't have really any issues with the treble overall.

The nicest part about the treble is that it maintains the level of good detail and clarity without any sense of sibilance or harshness even at higher volume listening.

At higher volume listening, the treble can be much more engaging and energetic. The standard moderate volume listening isn't particularly dark but the treble really does scale well at higher volumes without seeming bright.

Treble Score: 8.25/10 - TL;DR: Very safe yet airy; higher volume still keeps this sense of cohesion without ever getting harsh

Detail, Separation, Imaging, Overall Soundstage, Etc.: The most surprising thing was that the KE4 is super competent in the technical aspect but I was craving a bit more for the price/performance/expectations based on the general sound signature.

I was also a bit surprised that the sound stage was a bit more closed than I'd have anticipated based on the drivers and the overall impressions that I'd watched/read about. It's not particularly wide sounding which almost feels contradictory to how detailed everything generally is.

Don't get me wrong, I don't think the separation and imaging is bad at all. Quite the contrary, they're good enough. I think the general detail replay is good to great as well. But, they won't necessarily appeal to people that were expecting more performance from a $200 set that's tuned to this new 'meta' or 'neutral' philosophy. And, I do think there are some sets that are more affordable that provide better technical performance. But, the KE4 works well enough.



Technicalities Score: 8/10 - TL;DR: Average sound stage. Good instrument separation and detail but loses out a bit to slightly more expensive sets or more technical/cheaper sets

Library Hit List: I found myself enjoying a lot more rock/instrument heavy music from my library vs any form of EDM or bass-heavy tracks. Some of the best were:

The Black Keys - "10 Lovers"
The Black Keys - "Gold On the Ceiling"
AC/DC - "Back in Black"
The Wombats - "Be Your Shadow"
Queen - "Bohemian Rhapsody"
Weezer - "Buddy Holly"
Arctic Monkeys - "Do I Wanna Know?"
Camille - "Le Festin"
Grizzly Bear - "Mourning Sound"

I think female vocals, classic rock or music that isn't really typically full of warmth or emotion tend to come across the best here. There's just that missing bit of note weight, to my ears, that makes it harder to recommend if you're looking for full sounding male vocal oriented music or anything that typically draws a lot of emotion out.

Comparisons: So, I was wondering what the best sets to make a good comparison would be and I think, for their price range and what they bring to the table, the Kiwi Ears KE4 compares best against some of the Aful releases.



Aful Explorer: Where the Explorer is a high volume marvel for warm music and tonality, I think the KE4 is a high volume neutral/technical type of set that works very well for some music libraries. They both have a very 'chill' type of balance to sound. They can both coexist (kind of like the MagicOne and Explorer can coexist) but, 10/10 times, I would reach for the Aful Explorer more. Aful Explorer > Kiwi Ears KE4
Aful MagicOne: This was actually much harder for me. I think, head to head, I prefer the KE4 overall but I think the MagicOne, being a single BA, just has a bit more of that special sauce and the overall detail/refinement shines more to me if I was looking for a neutral set. Still, in a vacuum, I would take the Kiwi Ears KE4 over the MagicOne like 6/10. Kiwi Ears KE4 > Aful MagicOne

I was considering a comparison against the Estrella, etc. but I don't think the KE4 competes necessarily as well as them in terms of musicality or general performance; it's not to say the KE4 is bad but it doesn't do anything particularly well to trade blows with higher priced sets.

Other Things to be aware of:
The Kiwi Ears KE4 really falls under that 'Jack of all trades, master of none' type of set. There really isn't any deficiencies and I could absolutely nit-pick on everything but the KE4, at the end of the day, sounds very good and balanced.

Is it too safe? Probably. Will it stand the test of time? I'm not quite sure. But, as far as a chill/relaxing set goes, the KE4 works.

Volume Listening: Again, similar to the Aful Explorer, I think the best way to enjoy the Kiwi Ears KE4 is to bump up the volume a bit. There is no treble harshness but it really helps open up the bass to be more impactful and offset the very fast decay that almost makes the bass too lean/thin.

Source Synergy: To salvage a bit of the safe neutral/balanced tonality, I think the Kiwi Ears KE4 pairs very well with warmer sources. Something like the Onyx XI1 helped give it just a bit more note weight and made it just a bit more musical. Running it off of my JDS Element 3, adding just a bit more mid-bass really gave it a fuller sound that was more aligned with my personal tastes.

Special Sauce/Personal Bias Score: 7.5/10 - TL;DR: It's a very nice set that could work for a lot of people depending on their library. I don't know if it's leading in anything but it's definitely a 'Jack of all trades' type of IEM. It is definitely one of the better Kiwi Ears that I've tried, though.

Conclusion:
Warning: Philosophical notes ahead.


*I don't know I'm right, this is just my personal take, IMO*

I think the value that the Kiwi Ears KE4 brings is really figuring out your sound preference. Sure, I think there may be a lot of people who would appreciate it as is but I'd argue that some of the value that comes from this new 'meta' or 'neutral' tuning is that it's almost like a 'resetter' of expectations or preferences.

Ultimately, what I think Kiwi Ears has released is a very clean, safe, neutral yet not boring set. If I was going to just end up characterizing the KE4 as anything, it's neutral in the best way possible.

But, what I also think Kiwi Ears has done is given people the opportunity (that are really looking to chase after the next thing) a great way to distinguish the most important things that they're chasing. If you use the KE4 as your new baseline, you can figure out the most important things for your own HRTF. Maybe that would be the extra value added on top of a set that does things well - not the best but does everything well - but that's just my own musings.




Final Weighted Score: 7.85/10 - This puts the score at 3.925/5 which is enough to round up. While I do not think the KE4 does anything extremely special, it does everything good enough and can be a gateway/baseline for others to really dial in what they want while getting technical performance outside of that budget IEM range.

Thanks for reading!

Summary
The KE4 is the latest release by Kiwi Ears, and it has been getting a lot of hype. So what is the KE4 and most importantly is it worth the hype? So the KE4 is a hybrid iem with 2DD+2BA driver configuration, coming in at 200$. Build and design is decent, fit and comfort are good, packaging and accessories are decent. In terms of sound, Kiwi Ears has gone for a more well bodied, warmer, a bit relaxed version of the Harmon tuning with sub bass boost. I personally find this “new meta” tuning to be quite pleasing and very versatile and I think both general consumers and more experienced audiophiles will enjoy. Thus I can say it is totally worth the hype.



Intro
Hey Guys, whats up….
Today I am checking out the KE4 from Kiwi Ears. This is the latest release from Kiwi Ears and also a very hyped set. The KE4 is a hybrid iem with 2DD+2BA driver configuration, priced at 200$. So is this the best sub 200$ hybrid set right now? Lets discuss…

About the brand:
First, let’s get to know the brand, Kiwi Ears is a very popular ChiFi iem manufacturer famous for providing great value for money products. Bias aside, Kiwi Ears is one of my favor-ate ChiFi brands as I have used and tested many of their products, such as the Quintet, Orchestra Lite, Melody, Allegro. Anyways enough yapping lets get back to the KE4.

Disclaimer: thanks to Kiwi Ears for providing this unit, but as always this review is my unbiased and honest opinion.



Specs
> Brand:Kiwi Ears
> Driver: 2 Balanced Armatures, 2 Dynamic Drivers
> Sensitivity: 102dB (±1dB)
> Crossover: 3-Way Crossover Network
> Sound Tubes: 3 Independent Sound Tubes (for high, mid, and low frequencies)
> Driver Details: 1 Ultra-High Frequency Driver, 1 Mid-High Frequency Driver, 2 Low Frequency Drivers
> Impedance: 28 ohm
> Nozzle Diameter: 6mm
= PRICE: 200$

Packaging
Continuing on to the packaging section, this comes in a decent looking box but it is basically the same as their other sets. Sliding off the outtser sleeve you will find a simple black box with some branding on top. Sliding off the lid, you will see the iems beautifully presented in a foam insert. Below that you will find the hard shell case and some papers. Inside the case you will find the cable, eartips and some extra filters. This comes with a single set of Kiwi Ears Flex eartips, quality if which is good. The hard shell case is simple and practical. And the cable is good as well. I will get into more detail about the case and cable later. List of box contents:
Iems
Cable
Case
Eartips
Extra filters
Papers


Build and Design
Moving on to the build and design of the KE4, it is decent. This has a full resin construction similar to their other sets. The faceplate design is unique and minimalistic, it has metallic silver color surface with the Kiwi Ears logo in the middle, incased in a resin covering which adds depth giving it a 3d ish look. Other than the faceplate the shells are black with metal nozzle. The shells feel solid in the hands, the weight is standard. The shells are on the medium to larger side. Fingerprints and scratches were not an issue in my use case. The nozzle width and depth is standard. The 2pin connectors are flush type, I personally prefer recessed ones as they are a bit more secure.

Fit and Comfort
Talking about fit and comfort of the KE4, it is pretty good for my regular sized ears. Long term listening comfort is decent, nothing too crazy. Isolation is good. Breathability is ok. Stability is good. All in all I find it plenty comfortable for daily use.



Inner Structure and Tech
Let’s see whats inside the KE4. Kiwi Ears has gone for a hybrid set up for the KE4 with 2 balanced armatures and 2 dynamic drivers. The dynamic drivers are 10mm each and are arranged in an isobaric configuration. One of the two balanced armatures is a Kiwi Ears custom RAB 32257 BA driver. The other one is a Knowles 33518 BA tweeter.

Accessories

Cable
Now let’s look at the cable, Kiwi Ears has provided a pretty well made cable with the KE4. The color combination of brown and grey goes quite nicely with the KE4, but a white or silver cable would have looked even better. Build wise it has a 4core braid but I did not find any info on what wire it uses, I am guessing silver plated copper wires. The cable is on the medium to thinner side, I wish it was a bit thicker. The 4core braiding is nice and tight. The chin singe is properly functional. The cable is fairly soft and has no memory. The Y split and the connectors casing are metal and have nice weight, I like that. There is minimal audible microphonics, close to none. This terminates into 3.5mm, I wish this had modular terminations.




Please note: Listening impressions are highly subjective and can differ depending on different ear shape, individual music library, choice of source, eartips, cable and personal preferences, so your experience may differ. I personally always use and test all my gear in various setups to get a generalized idea on it. You can find my “tested with” info below.

Now most importantly sound, Kiwi Ears has gone for a updated or modified version of the Harmon tuning for the KE4, which many in the community is calling “new meta”. This sort of tuning fixes many of the complains people have with the stock Harmon tuning, which I must say I like this better. Over all sound signature of the KE4 is smooth, balanced with a sub bass boost. People who find the classic Harmon tuned sets fatiguing but still want a versatile sound, this is for sure one of the best if not the best option in the 200$ range in my opinion. Lets get into a bit more detail.

Bass
Let's delve into the bass performance of the KE4. This provides a bass forward yet well controlled presentation satisfying both in quantity and quality. Positioning wise, sub bass is more forward compared to the mid bass. The sub-bass feels visceral and very engaging. Mid bass is slightly less forward but it provides hard and dynamic slam. This does not get blotted. Bass speed is standard. Overall the KE4 has a very musical and engaging bass response, enough to satisfy general listeners and bass lovers but the quantity might not be enough for bass heads. The body and layering are executed well. Decay and reverberation are ok and bass note separation is satisfactory.



Mids
Moving on to the midrange, the KE4 takes a different approach. Unlike classic Harmon tuning we know, the lower mids are more forward and the upper mids are more smooth. Overall the midrage presence is positioned slightly backward similar to but not exacgly like U shape tuning. The mid bass bleeds into the lower mids giving it warmth and heft. The vocals are smooth, warm and relaxed. Female vocals have a bit of extra sparkle. There was no sibilance or harshness in the midrange. Instruments are natural but not in your face type. Personally I quite liked the attempt Kiwi Ears has taken for the KE4’s mids.

Treble
Proceeding on to the treble of the KE4, Kiwi Ears has gone for a safe tuning yet it is done quite nicely. Unlike Harmon tuning the treble here is much smoother and more natural with decent but not overwhelming detail. The overall resolution will not blow you away but I quite like the humble and natural approach. Level of energy is satisfactory, but personally I like a bit more energy and excitement in treble. There is no sibilance or harshness present, thus I can say this is a great choice for any treble sensitive listener. I find the treble tuning blends quite nicely with the full frequency range.

Technical Sound:
Soundstage of the KE4 is standard, not the most wide but not narrow either. All three plains are decent, this has good width but the height is ok. Stage depth is good. Layering is fine, but in busy tracks it may get blended in.
Imaging is better than average. KE4’s imaging is accurate and easy to pin point instruments.
Sound separation and layering is average.
Resolution is average
Dynamics are good
Timbre is good

Tested With
Source: cayin n3 ultra, cayin ru7, ifi uno, hidiz s8, apple type c dongle
Eartips: stock, Final E, spinfit w1, Divinus velvet, JVC Spiral Dots
Cable: stock
Music: Tested with versatile genre of music

Aful Explorer


The Aful Explorer is a hybrid iem, which is popular in the sub 100$ price range. The Explorer consists of 1DD+2BA driver configuration, coming in at 120$. I have previously checked out the Explorer and I quite liked it because of its uncommon tuning approach. So how does it compare to the KE4? Lets dive in..
Starting off with packaging, both are standard. In terms of accessories Explorer is better. Build and design wise, I like the look of the Explorer more but build is same. Fit and comfort wise Explorer is better because of its smaller foot print. Getting into sound, bass is more prominent and has more quantity in he Explorer compared to KE4. Explorer’s mids are more laid back and recessed compared to the KE4. Similar to the mids Explorer’s treble also takes a more relaxed approach compared to the KE4. Technicalities is better on the KE4. If you are looking for a even more relaxed set with good quantity bass, Explorer might be it.

Simgot Supermix 4


The Simgot Supermix 4 is very popular quadbrid iem in the 150$ price range. The Supermix 4 consists of 1DD+1BA+1 Planar+ 1PZT driver configuration. I have recently checked out this iem and will be posting a review on it soon. This is one of my favs when it comes to Harmon tuned iems. So how does it compare?
Starting off with packaging, Supermix 4 is slightly better. Build and design wise they both are a tie. Accessories are also a tie. Fit and comfort wise KE4 is slightly better. Sound wise, bass is more impactful and stronger in the KE4 where as Supermix4 is more natural and well controlled. Mids are more lively and more forward in the Supermix 4. Treble is more energetic, forward and bright in the Supermix 4 whereas KE4 is more relaxed. Technicalities are better in the Supermix 4. Overall the tuning on the Supermix 4 is basically opposite of the KE4.

Kiwi Ears Quintet


The Kiwi Ears Quintet was a pretty popular quadbrid iem in the sub 200$ price range and it is still one of the best sets Kiwi Ears has ever made. The Quintet consists of 1DD+2BA+1 Planar+1PZT drivers, coming in at 220$. I have previously checked out this set and it has been in my collection for quite a while. So how does it hold up against its newer brother?
Starting off with packaging and accessories its almost same. Build and design wise, I like the Quintet build better but design wise they are a tie. Fit and comfort is also almost same. In terms of sound, bass is more forward and stronger in the KE4 whereas the Quintet has a more balanced and well controlled bass. Midrange is more natural and more lively in the Quintet and KE4 mids are more relaxed. Treble is more forward, bright and energetic in the Quintet whereas KE4 has a more relaxed and safe tuning. Technicalities is better in the Quintet compared to the KE4. All in all the Quintet has more upper mid and treble focus with great detail and energy compared to the KE4 which is more natural and soothing with decent bass.

Rating
Sound: 5/5
Fit and Comfort: 4.5/5
Build and Design: 4/5
Packaging: 3.5/5
Accessories: 4/5
Pricing: 4.75/5
Total rating: 4.5/5



Conclusion
So to conclude the review, do I recommend this set? I highly recommend this set if you are looking for an easy going set with natural and balanced sound with decent bass. I personally find this “new meta” tuning to be a more versatile version of harmon tuning which I think both general consumers and more experienced audiophiles will enjoy. The pricing is also good on this set in my opinion. Big props to Kiwi Ears for such a great all rounder set.
And huge thanks to you all for sticking around, see yall in the next one.

Kiwi Ears KE4

Price 199$, so about 800 PLN



MANDATORY INTRODUCTION

Dear reader, please keep in mind that whenever there is an opinion in a review, it is my opinion, which may differ significantly from yours. We are all different from each other and have different tastes. Something, that does not give me an accelerated heartbeat, may bring you much fun, so I always recommend listening before buying, if there is such an opportunity. I would also like to point out that in the evaluation of individual parameters, as well as the entire set, I try to relate to the price level that has been set for them, which simply means that any opinion I give should be followed by the thought “.... for its price”. I believe this is the only fair form of evaluation and best represents the value of the reviewed item.



INTRODUCTION

Courtesy of Kiwi Ears, today I have the opportunity to introduce you to their latest in-ear headphones, the KE4 model. This is a hybrid consisting of two dynamic drivers (2x10mm) and two Knowles balanced armature drivers (RAB 32257 and RAD33518), or 2DD+2BA. Sensitivity is 102dB, and impedance is 28ohm. The headphone itself is made of resin, medical grade, and everything is topped with a hand-finished metal panel with the manufacturer's logo.



PRESENTATION

The packaging is quite small, looking quite nice. Inside you will find: the headphones, the typical Kiwi Ears hard case for the headphones, and a set of tips in three sizes, i.e. S, M, and L. The tips themselves are the already well-known Kiwi Ears Flex model, which features an unprecedented soft silicone rubber construction and a charming light purple inner cap, as well as mesh at the outlet. Here's a brief description of these tips, taken from the best tip guide, from www.audioreviews.org, which has always been a good, resource for me, and you may find it useful too:



Personally, I agree with the above, but in the section on pairing with other tips, I am going to present some replacements that also accompanied me during listening.

The enclosed cable, the detailed specification of which is unfortunately not described on the package, I consider to be very good. It is terminated with a 3.5mm jack. It gives the impression of being well constructed, with no tendency to tangle. It is pleasant to the touch and overall looks very good. During use, I didn't have the slightest problems with it, nor did I feel the need to replace it with another - which is also what I expected from a product of this price range.



Now I would like to devote a moment to the other components we get, and it will be a very short moment because there are very few of them. In this price bracket, I think that enclosing a standard case (the same one you get for example with KiwiEars Forteza, for $59), a set of tips (even if good) is a bit small. I am convinced that even a small change in the quality of the case, such as raising the quality of workmanship, or the materials used, would contribute to a better perception of the whole set.

To sum up, we get: headphones, with a good cable, good tips, a standard case, and a feeling of insufficiency.



CONSTRUCTION

Normally I don't post this section, but in the case of the KE4 I thought it will be appropriate, especially for two reasons:

• the size of the headphones

The headphones are chunky, noticeably chunky. Compared to the Simgot Supermix4, or most in-ear headphones on the market in general, the KE4 is simply thicker, which may be a problem for some people - for me, it wasn't.

• Drive-flex

, which is the problem of air being closed inside the headphones when inserting them into the ear. In some people, this effect manifests itself as a clicking sound, produced by a dynamic driver due to the pressure of air pushing against its surface. In others, including myself, the effect is associated with a feeling of ear-cupping, or rather, irregular ear-cupping, which causes a sensation of uneven levels of fit sealing and simply annoyed the hell out of me.

From what I have read, this effect does not occur to everyone, and if you, the reader, are one of the lucky ones, I envy you. Fortunately, for those who encounter such an effect on their audio journey, there are ways to minimize this effect - choosing the right tips!!! About it more in the section PAIRING WITH TIPS.

LISTENING IMPRESSIONS

It's time to move on to the sound itself.

About what META tuning is and what it's all about, I invite you to visit the YouTube channel of a certain individual, The Crinacle, or some other channel of reviewers who will surely describe it better than me. For my part, I will stand by to describe more what I hear than what I see on the chart.

I find the sound to be neutral, of warm characteristics, with some boost in the sub-bass region, but thankfully not exaggerated. The neutrality we're dealing with here reminds me of that kind of studio sound, devoid of coloration, with no obvious bass or treble boosts. The sounds here have a pretty solid weight, and at no point in the listening did I get the impression that they were missing something. Moving on to another thing that can be noticed on first listening: the treble or high midrange sounds, while audible and even unexpectedly clear, are not at any time oppressive with this set. This may appeal most to those who are usually uncomfortable with the overexposure of these registers, or just treble-sensitive.

At the same time, this neutral sound presentation is not so completely linear. Apart from some sub-bass boost, it is my opinion that the entire set 'plays by the middle', i.e. presents the middle registers in the most exposed way, which is not a problem at all, because the mids are the best-sounding area of the frequency spectrum here, but one step at a time:

BASS

In the case of the KE4, the bass here is a bit characterless. There's quite a lot of it, and there's no shortage of sub-bass, so the tracks don't lack punch when such is supposed to occur. Admittedly, the bass guitars sound quite natural, although the bass here does not impress. It's not bad, nor it is exceptionally interesting - it just is. Let’s leave it with that.

MIDS

As I wrote earlier, the midrange is the most exposed area of the frequency spectrum here, and in the case of the KE4, that's a good thing, because it's also presented the best. Drums, percussion, acoustic guitars, classical guitars, and other similar instruments most often identified with “the mids”, here sound great. The clangs, the snaps, the finger strokes on the surface of the taut skin, and other beautiful crunching sounds of this type delighted me more than once and in many tracks.

Female vocals sound beautiful and very sensual. Thanks to the tuning ( META?), female vocals are not prone to being shouty or project exaggerated sibilants. It is natural and sensual. A little more about the sound of the female voices in the DESCRIPTION OF SOUND BASED ON EXAMPLES section.

Male vocals have not been unaffected by the new META tuning either, but this is where the change causes some problems. What we used to call bass bleed on mids is now called by many a new neutral sound, and in my opinion, it sometimes negatively affects the sound of male vocals in the case of the KE4. In tracks where male vocals occur simultaneously with a fairly large portion of bass sounds, it sounds a bit like it is muffled, and loses clarity. Voices get at times drowned out, scattered, well, and thus less natural and transparent. This effect fortunately occurs only in some mementos and tracks. An example of such a track is The Arcs “Put a Flower in Your Pocket”, where the voice of Mr. Dan Auerbac of the Black Keys, when rings out along with the low and, in the case of the KE4, somewhat booming bass, blends in with the rest of the instruments and loses its presentation. This is not some very tiresome effect, but noticeable.

TREBLE

The high registers, although, as I mentioned earlier, are characterized by a rather certain withdrawal, I can't say that they are badly presented, on the contrary, they sound selective and natural. Percussion cymbals are very well audible and at times even give sparks, but they do not tire or irritate. The KE4 also handles heavily congested tracks very well and, for example, in some metal songs, where the roar of the guitars on overdrive and the scream of the vocalist furiously “summons Satan,” I was able to hear the specific place where the drummer's stick was hitting, which actually impressed me much.

TECHNICALITIES

Another thing that one pays attention to rather quickly are very good technical capabilities, specifically the imaging and separation of instruments. Songs based on live instruments benefited the most, as it was easy to separate individual guitars from each other, or different instruments in general. A cool effect that I personally appreciate, and I think that musicians, but also just people who like to listen to all the component sounds of the songs, will appreciate it too. I think this set will be great for drummers, because, although I've never been a drummer, I had a ton of fun listening to the transitions across the various elements of the drums. The separation of sounds located in the lower registers of the frequency spectrum is a bit more difficult, due to the fact that the bass here is a bit devoid of character and simply blends with other sounds from this area, but it is not tragic. Surprisingly, this set copes well with heavily congested tracks, e.g., metal tracks, and in general I think it can be suitable even for this genre of music.

PAIRING WITH TIPS

Despite its quite large size, the earphone itself sits comfortably in the ear and while using them I can only describe the comfort as without complaints. Likewise when it comes to passive isolation: it is very good and provides effective isolation from ambient sounds. As I wrote earlier, the only problem I had was with drive-flex, that is, air being closed in the ear, when inserting the earphone, but fortunately this effect was not very troubling to me, as I managed to find tips that effectively minimized it:

Whizzer ET100

• I liked the pairing very much
• the sound is detailed and selective
• no registers bothered me
• they somewhat restrain the excessive presence of bass, making the sound more balanced

Tangzu Sancai Wide/Balanced

• both versions of these tips worked very well with the KE4, both in terms of eliminating the drive-flex effect and keeping the bass from being overly exaggerated
• I assume that due to its porous surface, the air is not sealed when inserting the headphone, but escapes through the slots until it is fully sea

DESCRIPTION OF SOUND BASED ON EXAMPLES



Mark Lettieri - Barreleye, or Tidal Tail

• A piece practically consisting of just bass guitars and drums
• thanks to great imaging and separation of the instruments, we can play the game “count the basses” without too much trouble, as they can be easily distinguished with KE4
• the song is presented in a very engaging way with the right dynamics
• the right strength of notes makes the bass guitars sound majestic and firm
• great set for this type of music (funk)

Kendra Morris - Concrete Waves

• beautiful-sounding female vocals
• very good separation of instruments (guitars, keyboards, overdubbed vocal tracks, drums - everything selective and in its place in space)
• lack of even the slightest inconvenience in the sound
• percussion in the heard in the background, but still present, and the sounds of sticks hitting the cymbals can be well heard
• bass clear, concise, and pleasant

Koan Sound - Liquid Levity

• this piece in the genre of experimental electronics and has quite a few samples made from real instruments, such as violin, cello, double bass, piano, and real drums, and KE4 makes them sound very organic
• those sounds from 1:30 onward which come out of nowhere and swirl around your head, sound just great - separated from the rest of the track
• and those sounds from 2:00, coming from a closer-unspecified friction-based instrument, with their organic sound, can make the hairs on your hand stand up – impressive and engaging presentation

Nine Inch Nails - The entire Fragile album

• I'll start by saying that I've been a NIN fan for many years, but that doesn't change the fact that :
• KE4 play this album very well
• the sounds are spacious, organic, and dynamic in presentation
• the weight of the notes here works very positively, both on the guitars and the drums
• for example: sub-bass in the track “No, You don't” shakes the ground with its strength

Foo Fighters “ Everlong”

• this, already iconic track, has one of the more recognizable rock drum lines ever recorded
• every sound on the hi-hat is clearly audible and not in any way intrusive, as is the snare drum hit and main drum - in my opinion, you could easily recreate every hit in your head
• vocals also sound natural and in this case, I did not get the impression that they were drowned out
• clear guitars, but for me the star here is the sound of the drums

If you're interested, I invite you to check out my playlist on TIDAL, which includes tracks that caught my special attention during KE4 listening. By this, I mean tracks where some elements sounded to me in a unique way, not always on the “plus” side, but always unique .

SUMMARY

Who is this set for:

• musicians, especially drummers because of the imaging and separation of instruments
• fans of acoustic, classical, but also rock guitar sounds, those who like to listen to what riffs a song is constructed of
• people who are sensitive to high tones, but at the same time like selectivity in sounds
• lovers of natural, organic sound presentation
• people for whom imaging is of great importance

, not for:

• bass-heads, because too little bass and not fascinating
• treble-heads, because there is not enough treble, although the quality of treble sounds is quite impressive
• fans of entertaining, energetic sound
• lovers of detail

In conclusion, can I recommend this set? By all means! It is a very interesting alternative to quite popular Harman-based tuning, with solid note-weight, natural, organic sound and great imaging. A very good set. Recommended.

DISCLAIMER

I would like to thank Linsoul for providing this review unit.

The Kiwi Ears KE4 can be gotten here: https://www.linsoul.com/products/kiwi-ears-ke4 (no affiliate links).




SPECIFICATIONS

• Driver configuration: 2 x 10 mm isobaric dynamic drivers + 1 x RAB 32257 balanced armature driver + Knowles RAD 33518 tweeter
• Frequency response: 20 Hz - 40000 Hz
• Impedance: 28 Ω
• Sensitivity: 102 dB
• Cable: 2-pin 0.78 mm; no information on cable materials; 3.5 mm termination
• Tested at: $199 USD

ACCESSORIES

Other than the IEM, these are included:
- 3 pairs of Kiwi Ears Flex silicone eartips (S/M/L)
- 2 pairs of spare nozzle filters
- Cable
- Carrying case

For something almost touching $200 USD, the accessories are disappointing. Gear at this price point usually incorporate a selection of tips, or even modular cables, when we have only one type of tips on offer here.




Nevertheless, the sole set of eartips provided here are the Kiwi Ears Flex tips, which are made from hypoallergenic medical-grade silicone. These tips retail at $14.99 USD for 3 pairs (https://www.linsoul.com/products/kiwi-ears-flex-ear-tips), and are designed to be bass enhancing, with a ear wax guard within the stem. They are also soft and supple, and do not cause discomfort in the ears.

As their name suggests though, there is some driver flex present with the Flex tips and KE4 pairing. But driver flex is partially dependent on ear anatomy and type of tips used, so the driver flex component may be mitigated with aftermarket eartips.




The included cable is a 2-pin one. Even though it is on the thinner side, this cable is supple with minimal microphonics. There's a chin cinch for securing the IEM during usage. Unfortunately, we do not have any information on the cable materials but it is very serviceable.

Next, we have a small semi-rigid zipper case. There's inner webbing but the case is a far cry from the larger ones we usually get at the $200ish range, so it can only fit the KE4 without space for other stuff.



Kiwi Ears has included 2 pairs of spare nozzle filters, which are useful if the stock ones get clogged by debris or moisture.

The rest of this review was done with the stock cable and stock Flex silicone eartips. No aftermarket accessories were used, so as not to add any confounders to the sound.


BUILD/COMFORT



Fashioned from medical-grade resin, the housings are quite agreeable in fit, with an inner concha protrusion to assist with ergonomics. The shells are light and this IEM can be used for prolonged listening sessions.

Isolation with the stock tips is above average and the KE4 can be used in noisier environs. I encountered driver flex as detailed above.




INTERNALS

The KE4 packs a 4-driver setup:
1) 2 x 10 mm isobaric dynamic drivers handle the bass.
2) 1 x RAB 32257 balanced armature driver takes care of the midrange
3) 1 x Knowles RAD 33518 tweeter settles the treble

These are arranged in a 3-way passive crossover via 3 independent sound tubes.


DRIVABILITY

I tested the KE4 with the following sources:
- Apple dongle
- Cayin RU7
- Chord Mojo 2
- Fiio KA11 dongle
- Fiio KA17 dongle
- Khadas Tone Board -> Schiit Asgard 3 amp
- Onix Alpha XI1 dongle
- Questyle M15 DAC/AMP dongle
- Sony Walkman NW A-55 DAP (Walkman One WM1Z Plus v2 Mod)
- Sony Walkman NW A-55 DAP (Walkman One Neutral Mod)
- Sony Walkman NW WM1A DAP (Walkman One WM1Z Plus v2 Mod)
- Smartphone

This IEM is moderately easy to drive. However, while it can hit adequate headroom with weaker sources, the KE4 will scale with amplification in soundstage, dynamics and bass tightness.


SOUND & TECHNICALITIES

Graph of the Kiwi Ears KE4 via IEC711 coupler. 8 kHz is a coupler artefact peak.

Tonally, the KE4 can be described as having a neutral with sub-bass boosted signature. It is quite vanilla and laid-back, with a pleasant soundscape with no harsh dips or peaks anywhere. This tuning is one that is suited for marathon listening sessions as it is like sinking into a warm blanket. Conversely, those looking for aggressive or fun sonics might need to look elsewhere. But compared to the run-of-the-mill Harmanish sidegrades, the KE4 is certainly different.

The KE4 is sub-bass focused. It is no basshead IEM - bass descent has just a slight rumble without rocking the jaw - but the bass is relatively speedy. There is a slight mid-bass bloom that adds warmth to the lower mids and thickens the overall signature, though texturing is blunted.

The midrange is neutral but lush, warmed by the bass blow back. With 8 dB ear gain, the upper mids are not shouty, and overall the mids are euphonic and will please midrange lovers.

The treble is smooth with not an ounce of sibilance. While not a dark treble, the note edges are somewhat rounded with no ice-pick cymbals and high hats, so resolution and clarity may take a back seat. Treblehead or analytical junkies might find the KE4 a bit too laid-back here.

There is a slight whiff of BA timbre in the higher registers, which is more prominent when acoustic instruments are showcased. However, it has to be said that this is not the worst offender compared to other hybrids in this arena.

The KE4 is decent in technicalities. Soundstage is quite wide when amped, but there is a slight veiling of micro-details due to the tuning choices. Imaging is quite accurate with decent instrument separation. The KE4 goes for musicality as a priority over outright technical prowess. For a relaxed tuning, the KE4 still manages to capture some resolution but is arguably not class-leading in this department.


COMPARISONS

The KE4 will be compared against other hybrids residing near the $200 USD range. Planars, pure BAs and single DDs are left out of the comparisons as the different transducer types have their own pros and cons.


Juzear 61T Butterfly


Graph of the Kiwi Ears KE4 versus Juzear 61T Butterfly via IEC711 coupler. 8 kHz is a coupler artefact peak.

The 61T is a warm U-shaped hybrid. It is a bit more recessed in the midrange and isn't as thicc sounding.

The 61T has a worse BA timbre - this may be a deal breaker for some - but the Butterfly has better imaging. Soundstage is superior on the KE4 though, and it sounds less compressed.

The 61T is better accessorized, and has no driver flex.


Binary x Gizaudio Chopin


Graph of the Kiwi Ears KE4 versus Binary Chopin via IEC711 coupler. 8 kHz is a coupler artefact peak.

The Chopin has a more contentious tonality, featuring a massive scoop out in the lower mids and mid-bass, which makes it sound very anemic and sterile in note weight. It doesn't sound as natural or lush as the KE4, and the Chopin suffers from a more metallic timbre.

In technical aspects, the Chopin has better micro-detailing but loses in soundstage to the KE4.

Of note, the Chopin may also be ill-fitting, due to a unique teardrop like design. Additionally, the Chopin has a low impedance, which makes it fussy for source pairing (especially with gear with high output impedance), whereas the KE4 is more source agnostic.


CONCLUSIONS



The Kiwi Ears KE4 sports a less commonly seen neutral with sub-bass boost tuning. It is a sea of change compared to the dime-a-dozen V-shaped or Harmanish gear we see mushrooming out on a weekly basis, and is definitely one of the more memorable IEMs I've come across this year.

The pleasant tonality is amalgamated with a dulcet midrange and rounded note weight, and this IEM has a smooth treble that will suit the treble-sensitive to a tee. Cymbals and high hats are not splashy, with no sibilance nor fatigue. On the flip side, those that are treble-inclined or want lots of energy may have to consider alternatives.

Some may call this a "meta" tuning, but epithets aside, the KE4 is agreeable and pleasant for long listening sessions, allowing one to just lie back and relax into a pot of sonic honey. There are just slight compromises in micro-detailing and resolution, but when juiced well, the KE4 is actually quite expansive in soundstage, beating some competitor hybrids at this price range here.



In terms of non-sonic areas, the KE4 has good comfort and above average isolation, and is relatively easy to drive. However, the spartan accessories and slight driver flex loses a few marks in my book. Nevertheless, accessories maketh not an IEM - and the driver flex may be mitigated with aftermarket eartips - and I'm happy to recommend the KE4 as something contrasting from the usual fare, in a good way. Musical, melodious and mellow are fitting terms for this "meta" KE4.

(credit to @vandung2510 photograph skills)

Yes this is going to be a word review, yay
If you're interested in graph comparison, here's the link
Disclamer:

+ I'm a normal asian dude with some music producing background
+ I like clean balanced sound signature with focus on sub bass and lower treble
+ Can consider myself as treblehead
+ 60-68db listening session
+ Avarage 4/10 (Quarks/ 7hz Zero), Good 6/10 (Tanchjim Kara), Endgame 8/10, Bias Endgame 10/10
: Good, but with a catch
: Worth the money
: Specialist at something else
: A Very close to perfection
: Perfect for me

Click to expand...

- Bass: Good bass overall, good driver and tuning.
+ Kick drum feels authentic and the resonance after the kick is visible,
+ Bass have a decent of heft and rumble
+ Unfortunally driver don't have much air (or easeness, or flexible) enough to really brings out all the detail
- Mid: Good tone and timbre
+ Acoustic have a little realist feeling to it
+ Lacking in detail specifically in texture make electronic instrument don't have much base (lead/synth)
- Treble: Just good treble, decent sparkle and shimmering, nothing to be nitpicking about
- Vocals: Very good male/female performance, natural position, have a decent edge with female vocals, maybe lacking a little bit of body in male vocals. Non fatigue with higher volume
- Soundstage presentation: Large living room with sound source far away (think of Tv). Good stereo imaging, ok layer and have decent height placement.

The Kiwi ears KE4 Universal Hybrid IEM
2DD x 2BA IEM

Priced at $199.00
Or $209.00 with the Allegro Mini


The "E" in the title KE4 stands for Electric Guitar..........maybe?

Hi Folks,
Welcome to the Redcarmoose Labs review of the KE4. Here the brand Kiwi ears in introducing a new IEM, with the verbiage saying it’s redesigned. Redesigned what? They don’t say in any of the readings I have done. I do (at times) read other reviews of products I have new for review, but in the KE4’s case, I simply thought it would be better to not go over any prior reviews. I’m going to guess this KE4 is Kiwi ears remake of the Forteza? The Kiwi ears Forteza was a slightly off sounding extremely experimental formation of a 6mm midrange DD, a 10mm bass DD and a single BA for treble. I only gave the Forteza 3 stars, and that was being nice. So as any conscientious company would do, they went back to the drawing board. Hey, I have so far reviewed a whole bunch of Kiwi ears gear and they have been wonderful. So maybe the Forteza was just a misfire?

Kiwi ears Orchestra 8BA $499.00
Kiwi ears Cadenza 10mm DD $34.99
Kiwi ears Quartet +2 10mm DD +2 BA $109.00
Kiwi ears Orchestra Lite 8BA $249.00
Kiwi ears Dolce 10mm DD $24.99
Kiwi ears Quintet 1DD +2 BA + 1Planar + 1PZT $219.00
Kiwi ears Melody 12mm Planar $89.00
Kiwi ears x Crinnale Singolo 1DD $79.00
Kiwi ears Forteza 1BA +1 6mm DD +1 10mm DD $59.00
Kiwi ears Canta 1DD + 2 Planar $89.00

Really Kiwi ears makes good stuff normally. I have heard everything except the original Orchestra and Quartet. So to get back to the Forteza, it was simply holding a BA occurrence of a bright treble in 80% of songs that while distracting is also tonally inept. Hay, these IEMs are made by humans and the best thing to do is keep-on-trucking. And guess what, they fixed everything here. Of course the KE4 is not a $59.00 IEM either. But what Kiwi ears did was include 2 10mm Dynamic Drivers in an Isobaric formation combined with a Knowles RAD 33518 BA for treble duties and a vented Custom RAB 32257 BA for the midrange. Now supposedly this follows a new Kiwi ears target curve too. This in-fact was one of the main reasons I didn’t want to read any reviews prior……only product information before writing this review.



So what did we get?
For starters great timbre. Yep any resemblance to the Forteza is history, and well as the fact that I will not write the word Forteza, ever again.......maybe? I want to describe my KE4 first impressions……..as they were really not that great? To where the BAs were slightly disjointed and the bass was grainy and wrong. 5 days of burn-in did the trick here. So yes, I recommend getting the KE4…………but even with how controversial burn-in is, just do it, as the IEMs will sound very different in the end. To describe the first noticeable things, the bass is that wonderful combination of impactful yet totally detailed. The bass has great speed too, and dramatically fills the stage with authority……bass authority.



The soundstage is more wide than tall (of course) and items are relatively still thick (front to back) in size! I like that! There is an overall balance giving me the impression that this IEM contains a smooth pinna gain and clear vocals, but not really becoming a vocal centric listen. And really for the most part Kiwi ears have threaded the needle here coming up with a very well rounded and entertaining listen, somehow bypassing any of the pitfalls encountered with pinna gain heat, while still keeping the signature bright and entertaining. This results in a 2019 v2 smoother Harmon tune, with less energy slightly before the 3kHz peak as well as a subdued yet careful treble.......still holding a nice 14kHz send-off. As such a high frequency 14kHz holds very little energy to influence the character stature here, meaning yes it is there and adds detail but is in no-way super bright. I will place a graph here to show you, as the KE4 does sound exactly how the graph reads.

The things like technicalities the graph fails to show, and probably this area is where the KE4 starts to gain superiority of its similarly priced counterparts. Call it realism for short, but the KE4 moved ahead to not exactly sound like any old Harmon you regularly come across.


Comparisons:
Top row: Kiwi ears Orchestra Lite 10BA, The 2X 10mm DD x 2BA KE4
Bottom row: The TANGZU Fudu Verse 1 1DD x 2BA, The SHOZY P20 14.5mm Planar and The Kiwi ears Quintet 1DD +2 BA + 1Planar + 1PZT

To guess why these examples of the IEM art were chosen, I was curious myself about how the KE4 would hold-up against the Quintet and Orchestra Lite……simply because those were prior successful Kiwi ears introductions. The wild cards were both the SHOZY P20 and the Fudu Verse 1 being....…number one I was curious to compare the Fudu bass against the KE4, and the Fudu was a little hard to drive, but is remarkable for the $89.90 price-point. So I was wondering what the less money Fudu money got you. Then the SHOZY was thrown-in just to represent the Planar community, as it was a recent new addition…adding pizzazz to the comparisons.

The comparisons were using the included $14.99 Kiwi ears Flex ear-tips, the Sony WM1Z and the SIMGOT LC7 cable in 4.4mm.

The included ear-tips:
Here the Flex ear-tips were slightly special in that they seemed to give the KE4 a slight advantage. In use I spent the good part of an afternoon simply listening to my regular ear-tips that I always use, then a few more different ear-tips and then switched back again to the Flex ear-tips. It seems the Flex does smooth-out the treble a little, that and fit was really nice……..plus they look different, yet are a great new product to use with all the comparisons. We find ear-wax filters on the nozzles, which also probably subdue the treble a little, at least that is what they sound like?

The Orchestra Lite:
Here there was surprising and expected synergy with the LC7 cable and Flex ear-tips. This SIMGOT cable is not the brightest and offers a subdued slightly darker midrange and even the treble elements are not as profound as some more silver additive cables. To where this combo is very very good, and the bass is substantial due to the 1Z. While you can tell it is all BA, the sound is very cut and dry creating detail but with fast decays and of a slight, ever so slight BA timbre. Switching to the KE4 we are right away greeted with a slower and deeper bass while this stage and midrange composite is holding both a warmer tone overall it is also expanded out through the lower bass stage to come-off in a way softer yet holding the dramatic presence of the newly installed twin DDs. So just like the KE4 is built, we are meeting-up with less overall brilliance of BAs like the Orchestral Lite parleys and witnessing a dose of buttery smoothness, with less midrange energy, yet sounding even more natural (to me). Gone is the dryness of the Orchestra Lite, replaced with both more realism and farther segregated imaging out into the stage. None of that multi-BA clutter was found. To me while still detailed I may be able to access the KE4 for longer listening sessions. To where upon hearing the KE4 first off here I was questioning the filled-in parts as being partial or inadequate or something, but after the Lite I found exactly what the KE4 is to be more my style and fully complete……seemingly better defined and yet more relaxed at the same time? It may of course have been in part due to the decays from the twin DDs, but somehow this quality seemed to travel up even to the lower midrange and offer enhanced harmonics in that department, to which (lower midrange) notes the Orchestra Lite were rendered colder, and thinner.

TANGZU Fudu Verse 1:
The fun part here is the Hybrid design of the Fudu is in a few ways comparable to the KE4. Yet where the KE4 is 5 grams and middle size, the Fudu is only 4 grams and super small……the Orchestra Lite is a chunky boy being 1/3 bigger than the KE4 and 8 grams in overall weight! Very quickly changing the modular plug on the LC7 to 3.5mm and taking the KE4 to a regular phone output we are still met with a nice balance of tone, ranging from the bass, to the midrange and the treble. To where sure.........get the KE4 an alternative source be it the Allegro Mini it comes with for $10.00 more or really a full-fledged DAP and hear the substantial upgrade. The Fudu is famous for needing a source other than a phone to tap into the inherent authority it contains when driven well. Jumping to again the 1Z in 4.4mm the Fudu changes into its split personality of adding lower midrange thickness and especially bass sculpturing and involvement. Though when we compare back to back the little Fudu while being great does not offer as big of bass, yet the Fudu bass is wonderfully detailed. It’s the midrange and treble which still take second place to the added harmonic overtones and realism the KE4 seems to offer nonchalantly? Still while the Fudu is thinner (and smaller staged) overall I still can’t believe how it upgrades its sound going to a proper source? In this instance though with the Fidu being $89.00, you simply still get what you pay for, yet better than so many under $100.00 ear-phones!

SHOZY P20 14.5mm Planar:
So this is for fun, but also in a way a calculated way to express just how different these two would be. At $139.00 the SHOZY is quite the deal, and even better when it goes on sale for $69.50! Where the SHOZY asks for more juice than the KE4, it also seems to be actually reserved in bass into a show of lesser dynamics and authority, which comes as a (shocking) surprise in these side-by-sides. I mean this is a Planar and a big one at 14.5mm. Let me just put it this way, the KE4 is both more vivid and holds a more separated stage and within that stage the instruments hold themselves into more contrasts with more realistic sculptures. This happens every once in a while where a top rated IEM doesn’t perform as remembered, wild?



The Kiwi ears Quintet 1DD +2 BA + 1Planar + 1PZT:
Any one that knows me knows I have pushed this Quintet as the second coming of Jesus. I mean for $219.00 it really is a lot of music for the dollar. As a Hybrid using four methodologies of drivers, Kiwi ears are really throwing a lot out at you. For a while, especially before 2019 there was kind of a ceiling to where brands didn’t offer as much treble detail and involvement till you spent at least $500.00 or over. Sure there were some examples of treble detail but they didn’t give you a kicking bass with it. To me and in my humble opinion the Quintet made progress to change all that. And when I reviewed it there were no other reviews, I just wrote about what I thought. Since I made a July 2023 thread to help celebrate the Quintet I have come to read others' impressions and of course when that happens you learn more. The main difference between the two is the KE4 is way more relaxed than the hyper treble and upper midrange encountered with the Quintet. So what is on offer is a safer tune, yet also not holding quite the separation or cut itemization held as fireworks upon encountering the Quintet. Studying graphs here you could be forgiven for not seeing the Quintet bass speed and sculpturing….because that is special, a special Hybrid ability. It is this separation in the mid-bass from the lower mids that brings about the feeling of more detail and vividness…….not to mention the almost edgy upper midrange and treble. To where really if you simply ignore the upper half, the Quintet makes the lower half of the KE4 sound almost congested? And until this point in the review that wasn’t an issue that I noticed? It may look like the KE4 has slightly more bass on paper, except this is a case of better Quintet defined bass sounding like more bass than it is.

Then:
Except here the KE4 does huge amounts better in the timbre department, and depending who you are and the style of listening you do, that single factor could in-fact mean the world?




Music:
This is the climax of the review, this whole music section, I’m simply having fun, playing tunes and describing the outcome. Also we as review writers often become too critical of a new invention, as nothing is perfect. But as you will read, if there is a fair amount of musicality, if the IEM bounces and rocks……..well that can make-up for almost any drawback in my eyes. I mean in the simplest review I would literally say nope I can’t listen to it, or I can listen to it…….end of story. But more than that the music should offer a set of ideas as to why I would keep coming back to an IEM, what does it do that is charming? So if this music section seems awfully long winded, it is because I wanted it to be that way……as at times simply plugging the IEM into your DAP and into your ears becomes all that is needed to express what an IEM is…….and that is what took place here.



Katatonia
City Burials
Lacquer
44.1kHz - 24bit
This song goes to impress due to both the vocals actually being in the perfect place in the mix, combined with this really fast and clear bass action. I don’t want it to sound like more than it is, but this bass is so very separated and holds such a perfect tone here. It actually seems close to what they may have wanted the effects to be when they recorded it? Right off the vocals and bass emphasis takes place opening at 00:13. It is one of those bass sections to where every note has a vivid physicality to it, to where you almost want to constantly be rewinding just to hear these perfect renditions. Of course just the fact they also have panned the bass into continuous different playful places into the stage. It may be the lowest notes that seem to add to the individual technical ability here. What I mean is yes the bass is great, but as you climb upwards there is not as much separation between lower midrange and mid-bass as some other IEMs. Yet the way everything is positioned with this number, you would hear the low-end as perfect, as at least better than the price asked. Also remember if the timbre is good with strings then it will move forward to align with the vocal timbre…..and that is exactly what we have here. At 03:07 to 03:28 there is an emotional breakdown that takes complete focus in the song, as when you take out elements, it is just as important as adding them in. Here the simpleness of the vocals (almost by themselves) is very special and very clear! Coincidentally most of the other songs on this album have great guitar, but this song is really focused on KE4 2X 10mm bass guitar and vocals.



Judas Priest
Firepower
Lightning Strike
48kHz - 24bit
Ok here we are met with a standard rocker. And the way I hear this is very guitar centric, meaning if an IEM does not do guitars well, or if there is a component of off timbre it becomes a glaring issue, no matter where the guitars are positioned here. The openers of rhythm guitar have a very correct timbre and tone as well as a positioning into the stage that is both forward but not strident or too much. I would call this perfect really. The left and right panned placement of the rhythm guitar has both a tonal presence and bounce. The bass can be heard tracking the guitar or vis-vera whichever way you choose to interpret this. At 02:32 the leads take both an out-front placement and seems integrated. And if you’re wondering why I’m choosing more Heavy Metal for these songs, because I found it works!



Soen
Lotus
Lotus
44.1kHz - 24bit
Gather around
All the things that we admire
To be here is where I wanted to be
To abandon who I was
Gather around
As we're pushed towards the fire
We've been tricked into believing that all starts and ends within our walls
Gather around
Holding close your sons and daughters
Promise them that we will all be alright
Let them know you love them all
Talk to yourself
Let your essence be the answer
While we chase the meaning of who we are
Navigating through a storm
Gather around and follow me
Something misled us to this
Wanting it all is poverty
Rich is the one who is free
To be the one who wakes up all of those who roam
Shake your head to the sides
Wake the animal inside of you
Run away from it all
Let the wildness be your home
Plant a tree, kill a man
Let your instincts be in charge of you
Where you walk, what you dream
Measures who you really are
Turn to your friends
Let them face the one you mirror
And the demons that now rest on your side
They will leave you on your own

So here we are hearing an important vocal song, really a beautiful vocal song. But there is more………..I can hear great guitar emphasis before the drop. I mean this would be the song that has you spellbound if you saw them live. The writing of this is so very natural and the KE4 is going with the program here, making this song become the special thing that it is. This band is so very together in this, loose but tight, you can tell they are blending together and swaying afloat. The exact guitar extras and accompaniment at even 01:13 are a profound joy to hear, and the KE4 is transferring that magic. The drum access are truly something to hear at 01:39 taking form and showing how each drum was mixed into a separate placement into the stage because a microphone was individually placed in each drum. And………especially the accents way out to the side of the stage at 01:43 to 01:44. At 02:49 all hell breaks loose and we are met with the lead…………….and “OH” what a lead! This is Head-Fi and about making a musical connection! It is the naturalness that is the final outcome of ideas to where it is these tones that take precedence over any other technicality on offer here.



Soen
Imperial
Illusion
48kHz - 24bit
This song could follow the last song in a live setting and it would work. Why am I writing, I should be listening. OH, ya I have a job to do, to explain what the KE4 is about. Here the drums are a little more forward than the last song and we can tell. The Fender Rhodes at the start never seems to go out of fashion. As such there is a Hammond B3 organ sound too placed on the outskirts of the stage…….and yep we can hear that too. Here the cymbal attacks are unique in that they are an airy glisten of effect, to where they don’t attack but are almost like air breaths. The matrix of bass guitar, vocals and the brighter cymbal accents are just right, but more than just right as the KE4 finds the underlying groove and lets it travel through the DAP into your mind. Really this is a better song than the last one, a hit really!



Hans Zimmer & Junkie XL
Batman v Superman OST
New Rules
96kHz - 24bit
This is a test song. Here I’m looking to find-out just how well the bass detail is and texture found. Also this is one of the first songs I will use to understand technicalities as far as bass speed. That and bass stage, to which this song is critical of all those things……meaning this song will let itself be performed back in a myriad of different ways, some OK, some good and some great…..here it was above the price point asked. Maybe there is something to the use of 2X 10mm DDs? At just 00:18 the drums hit, it is their tone and authority that matters here, that and the size they are found occupying the stage…………..and guess what? Yep, it is all win here so far. Really it is the decay that is so profound here. Now the crazy part is I like this song so much that I use it for both BA IEMs and Hybrids, and I still like the variation that takes place, as both ways are better than satisfactory often. Bass BAs are offering a clear window into the center of this song to where DDs offer a less clear but often more textured event. The synth at 00:48 is important as it is delineating the stage…….but there is one big drop that I’m waiting for……one monster drop that is telling of ability here. There is a pre-rumble at 00:55 seconds……..still this is all leading up to the event in question. 01:38 is it………..the drop has been launched and it holds reverberations but before those take place the actual tone in heard. And some IEM simply don’t have the balls to get it right, but the KE4 goes there, it goes there in flying colors. So much that the stereo effects of the drop is heard, and the after effects, and the sound continues off into the soundstage. Mission accomplished!

Cable:
The cable is nice. I used it, I would have used it more if it came in 4.4mm. But all and all it has a great feel and great accessories being they are an upgrade for Kiwi ears being all chrome. The other thing that’s nice is the blue and red tiny dots they at the factory went and added in..........in addition to the L and R markings on the chrome 2pin barrels. Even the chin-cinch is chrome as is the cable splitter.






Build:
The KE4 is maybe the best fitting Kiwi ears I have encountered? It really is, the combo of medium shell and 5 grams weight, but there is more. You can tell Kiwi ears didn’t just stick the parts into any old shell, meaning this 3D printed shell is really very curvy and new………a new advanced idea of the Universal Custom Database design. Somehow it is just more comfortable, way more comfortable than the Orchestra Lite and even more comfortable than the Quintet? Better fit means better passive noise occlusion. Each IEM has a serial number to itself, a single large vent off the side/back. The metal nozzles hold all kinds of ear-tips on with ease. You get the feeling that they are actually advancing in design and build when you hold the KE4 in your hands and place it close to your ears. The nozzle fits the Flex ear-tips in an uncanny way…..I can’t exactly put it into words. Yet the Orchestra Lite had a slight issue to where many ear-tips fit but the Flex ear-tips would almost seat to close to the nozzle end and there was nothing to hold the tips in an exact place, they even seemed to occlude the Orchestra Lites nozzle ports and had to be pulled-out. To where the KE4 nozzle length seems just right, helping to increase outside noise occlusion. The way I test noise occlusion is I have a fan across the room, I turn it on and it becomes a reference to all the IEMs I have tested the last couple years. When I put the KE4 in my ears I can just slightly hear the fan….from one to ten, I would give the KE4 a solid 10 points.


You even get two extra sets of nozzle screens.



The Allegro Mini and KE4:
While I never got a chance to hear the original Allegro Dongle, I have experienced quite a few Dongles over the last two years, enough to give a fairly accurate idea as to what the Allegro Mini is and what it is not. Upon first encountering the Mini it really is a true mini being incredibly small. As such you can flip it over (as TypeC USB works both ways, upside-down and right-side-up) to find the best way to utilize the form factor with your device. Yes it is a full-on upgrade from something like the Apple Dongle and better than regular phone out-put, plus it decodes pretty much all bit-rates which means get it even a DSD 128 and it chews it up and if your are into hi-res then you have those files reproduced honest to bit-rate.



The TypeC attachment works with Android, Windows, iOS and Mac. First thing I did was hook up a $1000.00 Cable and IEM and go to town. Gets way loud. The difference from this $24.00 DAC/Amp to a DAP that costs $1000s...........is basically harmonic overtones. Maybe lacking too is a little fullness, to where stuff is only slightly thin. But that said when the dynamics of the music start to take over, you will be surprised at the Dynamic Range, the quietness of the noise floor and the stage. Really a big stage and of course way better than a phone.

When things really got good was when I put on a hi-res file off my MacBook! Truly I almost take back some of what I just wrote. While remember it is a $24.00 purchase, but the improvement with hi-res over standard outputs are fully noticeable?

https://kiwiears.com/products/kiwi-ears-allegro-mini

The Allegro Mini supports high-resolution audio formats, including PCM up to 32bit/384kHz and DSD up to DSD128. Does it sound like a full fledged DAP, no.........but really it is incredibly easy to hook up to a laptop and get going with no software needed, at least on the MacBook Air it was like that. I’m guessing use will really be to attach it to a phone while out and about?



In use with the Kiwi ears KE4 I would describe the tone as cut off a slight bit in bass, but what bass is there is super fast and fun, the treble is also just slightly rolled off. And the midrange is really where the most action is…….but it is fast and holds a medium stage to medium large stage. Where differences from an audiophile DAP (or other Dongles) is added vocal and instrument density, things like reverberations get slightly left out and an overall thickness and harmonic complexity gets left-out. This comes as a slight surprise as you would think the heft of the twin 10mm used in the KE4 would compensate for any lack of juice, but that’s not it exactly plays out here. This is probably a damping power as the Mini gets super loud, and IS way better than stock phone output, and sure there is a nice stage and added bass, yet the end results sound slightly thin and sterile, which is crazy because it truly is the opposite of the tone the KE4 is about. I say all this only to inform you of the results, just in case you get the combo and think it will be a cheap ride into audiophile bliss, as there is a fair amount that this ($24.00 by itself, $10.00 in combo with the KE4) leaves missing. The other gripe I have is (a common result of DSPs and some Dongles) where the volume ramps-up rather fast in the first moments to adjust volume. Wait, what am I saying, rewind.........with the KE4 the Allegro Mini is the price of a sandwich out at a restaurant , so maybe it IS worth it..........so goes the audiophile? Just remember you can do better with any full-on Dongle at those regular price-points.



Packaging:

Conclusion:
It is almost 2025…….and a lot of IEMs have emerged this year. As of today I have written 46 IEM reviews for 2024 in total. And in retrospect the KE4 is not perfect but offers a relatively balanced and complete demeanor. The real way the KE4 lives is by slowly growing on you..............the way slightly toned-down signatures do. As you sit and meditate in this sonic forest............showing small animals are noted, the smell of the breeze………the weather starts to form. It is this slightly understated charm that starts to take hold the longer you listen. Due to the correct timbre arrived at the KE4 special qualities are Rock guitar and drums……..to where Rock guitar sounds especially right, holding the correct amount of energy in the mix, same as the bass. This idea of Rock guitar if out front can with the wrong IEM be a mistake to make any off-timbre noticeable, yet here we never have that problem. And me being a guitar player I focus-in on the guitar in songs and study either the talent involved or the recoding…….at times it is just the tone of the guitar that keeps me occupied, and here they have packaged that tone and served it on a silver platter.

Though:
At times I wanted more forward vocal placement, but that could just be me? To where Kiwi ears just made the $89.00 vocal Canta IEM, and the two could be looked at as complementary as vocals are way out front with how the Canta dances.

The KE4 walks a line of not being as bright as the Quintet before it, and holds better timbre than both the Quintet and Forteza……..and in many ways it even does better with timbre than the lesser priced vocal Kiwi ears Canta IEM. This often happens when manufacturers use name brand quality BAs (they are using one per side here) and if they choose to down-tune (a little) with a passive crossover….....the results really work. The IEM is built like a brick-schiit-house, yet only weighs 5 grams. The shape is incredible, so incredible that I wish every IEM was this exact shape, I really do!

In the end we are gifted with a relaxing tune and the Kiwi ears incurable dedication to finding just the right shape to make you go ahhhhhh. Probably the one thing I can say is that they were right saying this is a new tune for Kiwi ears, I hope they will continue down this path as it offers many avenues for success.

$199.00
https://kiwiears.com/products/kiwi-ears-ke4

Add $10.00 for the Allegro Mini
https://www.linsoul.com/products/kiwi-ears-ke4

Disclaimer:
The Kiwi ears KE4 has had full 5 days of continuous burn-in.

Disclaimer:
I would like to thank Evelyn Zhou from Kiwi Ears for the KE4 review sample.

Disclaimer:
These are one person's ideas and concepts, your results may vary.

Equipment Used:
Sony WM1A Walkman DAP MrWalkman Firmware 4.4mm balanced and 3.5mm single ended
Sony WM1Z Walkman DAP MrWalkman Firmware 4.4mm balanced and 3.5mm single ended
Samsung Phone 3.5mm single ended
HiBy R3 II DAP 4.4mm balanced and 3.5mm single ended
Apple MacBook Air 3.5mm output single ended
Kiwi ears Allegro Mini 4.4mm output balanced



If you are curious.....there is also a new Kiwi ears KE4 thread open.
https://www.head-fi.org/threads/kiwi-ears-ke4-guitar-god-universal-iem.974254/

Intro
Kiwi Ears have been around for quite the IEM scene for quite sometime as part of the Linsoul portfolio, blasting into the industry with the lauded Orchestra and its Lite version. Afterwards, they have been releasing some hits such as the entry-level Cadenza and Quintet along with some bits of misses with the Singolo and Forteza. This time, it seems they have something up their sleeve with the lowest priced 'JM-1' tuned set at $199 as of the time of this writing. I refuse to iterate 'meta' because... well, I know this hobby is still subjective and the term is kinda corny when applied repetitively in audio. Let's take a look at somewhat a winner in Kiwi Ears' stable and as early as now, I'd recommend a listen for those looking to add this to his/her collection.




Build and Inclusions
The KE4, as the number on the model suggests, comes in a 4-driver (2DD + 2BA) hybrid configuration. Packaged in the typical Kiwi Ears packaging of outer sleeve cover housing a black top-off box. The IEMs themselves feel very solid in full resin shell yet with a minimalistic design of a somewhat polished silver-gray faceplate with the Kiwi Ears logo. The ergonomics are really nice and provides a comfortable fit. Accessories include an above-average quality sturdy cable terminated in 3.5mm SE that fits the design, 3 pairs sizing silicon eartips, and lastly the usual Kiwi Ears clamshell zip case. Nothing more but still thankful for the essentials since these are still not of mediocre quality. Way better than Singolo's inclusions.

Sound and Comparisons
The KE4 provides a really nice balanced tonality and a hint of warm tilt. Kinda like a neutral with bass-boost signature but is still fun when the music calls for it. The bass is punchy, deep, and impactful while still having a smooth, non-peaky treble response that completements its overall balanced nature. Might I add that the timbre is natural and almost uncolored, sounds about right everytime whether a percussion hit, a chorus of male/female vocals, or a combination of strings. The KE4 also lends a sense of spaciousness to its sound, not sounding compressed and intimate. The downside to these all is its resolving capability. Its detail retrieval is not mediocre but not remarkable either with no surprises or is lacking the 'I haven't heard that before moments'. Vocals tend to be on the laidback side as well with midrange dynamics taking a bit of a backseat despite again, the naturalness of its timbre. Do not get me wrong, it's not a boring set. The KE4 is actually a fun balanced set especially when you turn up the volume wherein the usually tamed bass and treble at low listening volumes slowly jumps at you when the need for liveliness in your music hits. For comparison, the KE4 sounds like a more natural-sounding Simgot SuperMix 4 but without the somewhat lean midrange. The SuperMix 4 is also a bit more technical. With a $100 difference between them, I also favor the KE4 clean-sounding JM-1 application over the bass-heavy style of DUNU DaVinci. Despite the higher pricetag, the KE4 actually has better balance than the DaVinci and has even better midrange timbre than the nasal vocals of the latter. Lastly though, despite the technical advantages of the DaVinci, the KE4 even has a bit better treble response, not sounding blunted but still could use some sparkles and a bit of crispness.



Conclusion
Like what I mentioned in the beginning, the Kiwi Ears KE4 is a remarkable set in terms of attaining that 'JM-1' safe tuning, providing a balance of having a fun, punchy bass and smooth treble without the sharpness. Despite being a bit laidback, midrange timbre is on-point without coloration. All in a $199 package. It might not be for everyone, but it also has the least chance of giving a frown to someone's face when listening to it. It might not be for fans of extreme dynamism or excitement but still has enough chops not to bore, unlike other sets following its curve. Great job to Kiwi Ears with the KE4 and the accompanying pricetag does not hurt having to own this set as well.



Sidenotes:
IEM set has been listened via the Sony ZX-707, Astell&Kern Kann Alpha, and Kiwi Ears Allegro Mini separately using the stock Kiwi Ears Flex eartips over the course of multiple genres across FLACs (16bit&24bit) and streaming (Tidal). The Kiwi Ears KE4 is available through Linsoul for $199.99 - https://www.linsoul.com/products/ki...D_RdqWfF--EY3guFW9h7uPs5HmALQmqwGVKxfRsJLnIOA