KZ ZAS

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Knowledge Zenith ZAS Review: The Sassy One
Pros: Full-bodied lows
Cable quality is improved compared to previous models
Cons: Some sibilance
Shells doesn't feel like they're durable enough
Introduction:
Knowledge Zenith, or simply KZ, doesn't really need an introduction at this point. They are, by now, pretty much well-known by long-term audiophiles and newbies alike. They were already famous back in 2017 when I started to go down the rabbit hole of the hobby, and now 4 years later, they still continue to produce budget in-ear monitors that attract the average Joe. The ZAS is one of their most recent model and rocks a hybrid driver configuration in typical KZ fashion. The ZAS currently retails for 66 USD, and was provided to me for free by KZ in exchange for this review.
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International purchase link (Amazon)
International purchase link (AliExpress)
Philippines purchase link

Specifications:
Driver units: 1 10 mm dynamic, dual magnetic + 7 custom balanced armature
Impedance: 24 ohms
Sensitivity: 109 dB
Frequency response range: 10 Hz - 40 kHz


Source:
Poco X3 paired with FiiO KA3, iBasso DC03, Shanling UA1, Tempotec Sonata E35 and Zishan U1

Test tracks:
Africano - Earth Wind and Fire
Dark Necessities - Red Hot Chili Peppers
Gurenge - Lisa
The Chain - Fleetwood Mac
Monsters - All Time Low
Ours - Taylor Swift
Stay - Mayday Parade
Snuff - Slipknot
Yesterday Once More - Carpenters
So Slow - Freestyle
Aurora Sunrise - Franco
Attention - Pentatonix
Blue Bird - Ikimono-gakari
You're Still The One - Shania Twain
Anyone Who Knows What Love Is(Will Understand) - Irma Thomas
Salamin - Slapshock
AOV - Slipknot
Hey Jude - The Beatles
The Way You Make Me Feel - Michael Jackson
...and a lot more.

Unboxing and Accessories:
The ZAS come in a small rectangular black box, very different from KZ's previous boxes that were sleeved and white. The box opens like a book, and upon opening it, you will see the earphones inserted in a dense foam, and a metal plate below it that acts like a nameplate for the ZAS. Below the foams there are the cable, extra eartips, instruction manual, and a small quality control pass certificate.
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Build:
The bigger part of the shell is made of plastic, which seems to have a total of three segments not counting the nozzle and the faceplate. This makes it feel like the shells can easily break. The faceplates are made of resin with a metal piece around it, decorated by the KZ logo at the center. At the rear part of the shell, there are 2 small vents with the other one situated at the center of the dynamic driver. The nozzles are made of metal with a lip to hold eartips in place and a metal mesh filter to keep foreign objects out.
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The cable is a braided 8-core silver plated copper. The cable itself is soft and light but the bulky plug gives it a little more weight. The angled 0.75 mm 2 pin connectors are made of plastic, while the splitter and the 3.5 mm gold plated plug are made of metal.
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Now let's get to the sound.

Lows:
The lows are reproduced in a powerful manner. Subbass drops with authority. The depth is very good, able to present those really deep rumble, while the decay is a bit loose. Midbass is well-controlled and doesn't feel boomy or bloated.

Overall, even though the lows are dominant, the ZAS doesn't have it extreme unlike previous KZ models. This signifies that KZ is progressing and maturing with their tuning.

Mids:
The mids have that signature KZ presentation; slightly recessed. Vocals are linear, with the male and female voices sharing the same position and weight. The mids are also leaning on the thin side, which renders most instruments to retain their crisp sound even with the abundance of the lows. Shoutiness was never perceived but there are some rare instances where there is a very slight sibilance.

Overall, the mids are reminiscent of their previous models. It is recessed and sometimes piercing but just like the lows, improvements can be noticed in this section especially in the texture and definition.

Highs:
The highs are a step below the level of the lows. It has some emphasis, but not as much. Treble reach is great, but the upper end tends to be just a little too hot at times. String instruments in this section are gritty, cymbals have that splashy texture and defined well, that are highlighted by a slightly above average decay.

Overall, the highs are boosted but still within comfortable levels and does not cause fatigue even in extended periods of listening.

Soundstage and Imaging:
Soundstage expansion was never KZ's strength, but the ZAS is on of the better IEMs of KZ in terms of soundstage. The stage has an average expansion, with the width having marginal space than the height. Imaging is good and adequately clear. Instrument separation and layering are both slightly below average. There is also a fair but acceptable amount of congestion especially on complex tracks.

Conclusion:
KZ has been plagued by overwhelming lows, underwhelming mids, and superfluous highs for so long. With the ZAS, KZ has managed to reduce those flaws down to manageable, enjoyable levels. But of course, the improvement should not stop there. Considering the number of drivers the ZAS is equipped with, when implemented properly, the ZAS has the potential to perform extremely well in its given price point.

inevitableso

Previously known as bossunswitch3
A small step forward
Pros: Non fatiguing treble
Bass cannon
Build quality
Upgraded stock cable
Cons: A bit thin treble
Sub par technicalities
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𝙆𝙕 𝙕𝘼𝙎 - 𝘼 𝙨𝙢𝙖𝙡𝙡 𝙨𝙩𝙚𝙥 𝙛𝙤𝙧𝙬𝙖𝙧𝙙

Specifications:
Product Name:KZ ZAS In Ear Earphone
Impedance: 24Ω
Earphone sensitivity: 109dB/mW
Frequency range:10-40000Hz
Pin Type:0.75mm
Driver units: 7 balanced armature headset + 1 Dynamic driver

This unit was provided by KZ in return for my honest opinion about the product. I'd like to thank Love Jr David for the assessment.

We all know that KZ was one of the most popular Chi-Fi brand in the market, they've been dominating the ultra budget segment for years, let's take a look if they improved through those years.

Build Quality and Fit:
The build quality on KZ products hasn't really been an issue for me, except of course their QDC like pin which is a bit frail but overall the build quality is nice, the fit

Sound:

Bass: This is probably the most bass heavy KZ I've ever tried, the bass goes deep, as a basshead I kinda like it though the texture is just something you'll notice as too smooth or not that detailed, the decay quite slow it's noticeable specially listening to a fast bass tracks like Skrillex - Scary Monsters and Nice Sprites which sounds sloppy and messy. Overall it's more like a quantity over quality.

Mids: There's really not much to say about the mids, they're not as recessed as most V shaped KZ IEM, but due to the quantity of bass it bleeds through the mids sometimes, it still depends on the tracks. Overall, mids are good considering the amount of bass ZAS has.

Treble: This is what I'm concerned about on most KZ IEM's but this time they've gone into the right route, a smooth and non fatiguing treble, it's still has that metallic timbre which is reasonable but I just wish it has more body and not as thin as it sounds. Overall, it has a safe non fatiguing treble.

Technicalities:
This is quite a bit underwhelming specially the amount of drivers they've put into it, I was hoping it would benefit most on technicalities but sadly it didn't, soundstage is ok it has more width than height, the imaging is sub par due to it's nature of being a bass heavy IEM.

Conclusion:
KZ had done a great job on making an enjoyable set on a budget, they've definitely improved in terms of tonality but still fell short in improving on technical performance, would I recommend the ZAS? I would honestly say maybe, for those who's looking for a bass heavy set with a non - fatiguing treble. At the end of the day it's all a matter of enjoyment than being conscious and bothered by the tiny bit of details.

Product link to purchase : https://www.amazon.com/Headphones-H...ency-Cancelling/dp/B098JN8311?ref_=ast_sto_dp
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cappuchino

Previously known as sub30
TWO STEPS FORWARD, ONE STEP BACK
Pros: Bass cannons (extension is exceptional; still great even at 2x the price)
Decent soundstage
Excellent fit and comfort considering the size
New, decent 8-core stock cable
Responds well to EQ
Cons: Slight incoherency, particularly in the bass region
Bass cannons
Treble tuning (lacks sparkle and brilliance for my tastes)
Resolution, detail and clarity
Shell feels cheap considering the price
NEEDS EQ BADLY (for my tastes)
Disclaimer:

I would like to thank Cecelia and Knowledge Zenith for providing a review unit of the ZAS. Rest assured that my impressions written in this review are my own personal thoughts and opinions and in no way influenced by outside parties.

I am not an expert in this hobby nor claim to be an audiophile. I just love listening to music and am fond of writing articles.


Introduction:

The KZ ZAS is a 1 DD + 7 BA hybrid currently selling for roughly ~60 USD on multiple online platforms. The DD used in the ZAS is the dual-magnetic XUN driver with KZ’s own “updated” blacked-out BAs. There are two colorways available – silver and black (mic, no mic), with an impedance of 24 ohms and a sensitivity of 109 dB. Connection type is “Paragraph C.”


Oppo Reno 4 > Earstudio HUD100 MK2 (bypass, low power) > Transducer


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The KZ ZAS is easy to drive and doesn’t require further amplification. A phone will do.



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Build and Comfort: essentially the same shell as the KZ DQ6, only slightly larger and lighter. Fits excellently well for my ears without any discomfort and is surprisingly very secure. It is not resin-filled, and the IEM itself is extremely light for its size, too light even as it doesn’t feel premium at all (quite cheap-feeling on hand). I assume it’s because of the thinner/less dense resin used (compared to DQ6), as well as the acoustics chamber.

Faceplate is plastic, looks good on pictures, but feels cheap. There’s a rough edge at the pointed part but shouldn’t irritate your ear. It’s indicated in the marketing materials that the gold outline of the faceplate is made of metal but it doesn’t feel like it.

Nozzle is the newer KZ style, average length but below average width. You will encounter issues with aftermarket tips and I suggest that you use a nozzle adapter (I just DIY’ed mine from a foam tip I don’t use). Insertion depth will depend on the ear anatomy and eartips used.

One exciting thing regarding this model is that it now comes with a new 8-core cable. Quite thin for the number of strands it has. HOWEVER, it is very supple, light, comfortable and doesn’t hold the “rolled” shape and is a big improvement from their previous stock cable. I do have an issue with the left preformed earhook – it’s shaped awkwardly. There are several fixes for this: 1. reshape it so that it perfectly molds to your ear with some heat (I usually use a hair dryer), and 2. just remove it entirely (would be more prone to tangling). It doesn’t have a chin slider, but the jack is relatively heavy (metal) and feels high quality. Splitter is quite small and is also made of metal. Connectors are plastic.

Isolation is above average due to fit and shell size.


Package: 3 pairs of silicone eartips (S/M/L; not usable for my ears). Paperwork. 8-core cable.


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*size comparison of DQ6 (left) and ZAS (right).

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*KZ Au, Ag, Cu cable (left) and ZAS stock cable (right)


Now, onto sound:

For this review, the IEM was left in stock mode, without mods other than using whirlwind tips (w/ nozzle adapter), as well as switching to the KZ Au, Ag, Cu cable for aesthetic purposes, with a listening volume of low-medium to medium. As per my testing, I have found the ZAS to be tip-sensitive. Tip roll per user preference.

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Bass:
monsters. Whatever KZ sound engineers did to the ZAS to reach this deep is nothing short of exceptional. Sub-bass frequencies are easily reached and has serious rumble. Mid-bass contains heavy punch. Texture and control are sub-par considering the price. However, I have a feeling that the XUN is not the only one handling this region. From my experience with the DQ6, the XUN driver is of the faster side, both attack and decay-wise. The ZAS is different. It has a tendency to sound boomy especially with continuous bass hits. There are songs where you notice that it feels like a clearer (and cleaner) bass response is hiding behind the bass cannon persona. Good thing is that both play around the same speed but would show incoherency in bassier tracks.

Midrange: a mixed bag. Let’s get the obvious out first – it is recessed (excluding upper midrange a bit, but still applicable), close to the point of sounding drowned by the bass. Female vocals sound fine for the price, showing hints of thinness. Male vocals, meanwhile, are a different story. As I have mentioned a few sentences back, most of the midrange is recessed, and this include male vocals. It also has a tendency to sound nasal in some tracks. Peak is exactly at 2 kHz. No observed shouty-ness in my listening volume (low-medium). I do have to note that the midrange of the ZAS is… soft. Electric guitars don’t have bite, toms lack definition, and vocals don’t deliver emotion (subjective). One good takeaway from this is that the ZAS is very much fit for casual use.

Treble: mellow, non-fatiguing, and smooth-sounding but rolls-off after lower treble. Air extension is alright, nothing amazing (though almost inaudible when listening to music). IF you listen to non-bass focused tracks, you will notice how *mature* this treble tuning sounds like. BUT, OOTB, especially if you got used to more energetic highs, it will sound dead and muted at first, most especially due to the bass quantity/quality. In my experience, after a few songs, my ears got used to the signature. This is very, very different from the two other KZs I’ve tried (DQ6 and EDX) as well as the KZ hybrids I’ve read about. I have to say, this tuning would have been fine, fantastic even, if not for that bass. No sibilance nor harshness, at all. Lacks sparkle and brilliance but doesn’t show splash (though decay is faster than natural, as expected of a BA).

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Timbre:
Not the most organic, but also not unacceptably artificial. Decent considering it has 5 BAs but definitely shows hints of that BA timbre especially in the vocal region. Treble not so much due to its laidback character.

Soundstage, Imaging, and Separation: Soundstage doesn’t favor any dimension and is spacious (shell size plays a role). What is exceptional for the price is the depth due to how well-extended the ZAS is in the sub-bass region. Imaging, as well as separation, is as expected of a multi-driver IEM – good. Each instrument has a place of their own and won’t blur along the edges.

Detail-retrieval: Assuming that your ears have been “saturated” by the signature, it still won’t show 😂 Unless you really look for it, of course. The ZAS isn’t tuned to deliver a detailed and transparent sound. Sup-par detail, micro or macro in the price bracket it lives in.


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To EQ or not to EQ?


With Wavelet/AutoEQ being talked about in a thread I participate in, I remembered that I had said application download in my phone. And so, I run it, plug in the ZAS directly to the phone, search for the ASX, and set the EQ strength to 45%. The selection of the ASX EQ preset is under the assumption that the tuning shares similarities with the ZAS (can’t prove because I don’t have the aforementioned IEMs nor have I listened to them, but I have seen the graphs and they share the same generation BAs 🤷🏻‍♂️). As far as I know, the AutoEQ preset is patterned to mimic the 2019 Harman target. Do correct me if I’m wrong. Thank you.

So, how does it sound? Good. Like really good. Mid-bass is toned down to a degree (also sub-bass by a little) but is still present unlike full-blown Harman. Bass, in general, is definitely elevated (retains that rumble). Texture shows more and bass lines are cleaner. Midrange, and in extension vocals, show better resolution and definition (less recessed and airier, as well). The ZAS female vocals (w/ EQ) is a treat for female vocal lovers like myself. Instruments now exhibit texture. Treble has more, much appreciated at that, presence and better extension (finally some air and brilliance). Soundstage has even more “space/air” around the instruments. More detail perceived due to the increase in the upper frequencies.

2 kHz peak is also lessened and the preset favors ~3 kHz, which is much, much better for my ears.



*ASF and ASX EQ presets share similarities. Choose based on what your ears like more.

**EQ strength refers to how much dB is being added/deducted to or from the specific frequencies. Choose based on what your ears like more.

***I didn’t perceive any distortion when EQ was applied (indicated strength). YMMV due to differences in audio set-up.



Conclusion:


Is the ZAS a representative of Knowledge Zenith’s new image, as well as its tuning? If you ask me, I do think it is. However, as the ZAS appears to be of the first pages of this next chapter in their continuing legacy, we can only hope that it gets better from here on. A new and way better stock cable, excellent fit and comfort considering the size of the shell, great bass extension even at 2x the price, and relaxed highs – these are what makes the ZAS a compelling choice. However, you will have to deal with a whole lotta bass, recessed midrange, non-existent detail and a feels-cheaper-than-its-price-suggests build.

In stock tuning, I would definitely not recommend the ZAS for its price, unless you really like them bass. HOWEVER, if you are open to EQ, then it’s a 50-50 😊 Just needs a little cleaning up.



No EQ – 2.5/5

With EQ – 3.5/5



****If you have other questions/concerns with the IEM mentioned, feel free to message me****​
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DeltaAudio
DeltaAudio
nice review
M
MoonAndStar
I also own them. This review represents my opinion. Disappointed, to suffice.
chris the man
chris the man
Just chiming in here to see if there are any recent users trying these? From all graphs I have seen, they look quite impressive for the basshead within the price range!
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