KEFINE Klean

KEFINE

KEFINE is an emerging brand founded by a group of audio enthusiasts driven by their passion for the hobby. With prior experience in earphone manufacturing, they united to realize their vision of superior sound quality. The KEFINE brand is dedicated to producing earphones that deliver an outstanding price-to-performance ratio while ensuring high-quality sound craftsmanship. To date, they have developed three models: the Klanar, the Delci, and their newest addition, the Klean.



KEFINE Klean

The KEFINE Klean is a budget-friendly, entry-level earphone equipped with a 10mm dynamic driver that incorporates a diaphragm constructed from diamond-like carbon (DLC). This sophisticated material is recognized for its exceptional clarity, detail, and extended high-frequency response.

Additionally, the Klean is designed with a dual-cavity driver architecture and interchangeable nozzles to accommodate individual sound preferences. The silver nozzle provides a warm and smooth auditory experience, whereas the black nozzle produces a higher resolution with brighter and more transparent sound. The threaded design facilitates quick and easy nozzle changes.

Non Audio stuff

The ear-shells are crafted using an alloy casting technique and subsequently polished to achieve a sleek black finish. The faceplates are secured to the main body with screws, a method that mitigates the risk of damage from adhesive failure or external forces, thereby enhancing the product's durability. Similar to the Delci, the Klean is exceptionally well-constructed, exceeding all expectations given its price point.

While the design of the KEFINE Klean may appear simple and minimalistic, it possesses a level of sophistication and appeal. Although the ear-shells may not be particularly lightweight for their size, they are compact and feature a contoured design that conforms to the natural shape of the human ear. The Klean offers a high degree of comfort and a discreet appearance, seamlessly fitting into the ears to provide a stable and stress-free experience with effective noise attenuation.



Cable and accessories

KEFINE provides their earphones with premium cables, and the Klean model is no exception. It features a 2-pin detachable cable constructed from high-purity silver-plated copper wires, designed in a two-core braided format. The cable is equipped with a 3.5mm aluminum plug, ensuring it is both soft and lightweight, while minimizing microphonic noise and preventing tangling. This high-quality cable offers excellent handling and aesthetically complements the Klean, making it a worthwhile investment for the price.

The package comprises three sets of silicone ear tips, a cable, two sets of tuning nozzles, and an attractive carrying case featuring a side zipper.



Power needs

Entry-level earphones are designed to be easily driven, as the majority of consumers will utilize them through the 3.5mm jack of their smartphones or a basic USB DAC dongle. The KEFINE Klean features an impedance of 32Ω and a sensitivity of 107dB, making it particularly easy to drive. This allows for an enjoyable listening experience with portable USB DACs such as the FiiO JA11 or the Kiwi Ears Allegro Mini.

Audio stuff

Let's start with the silver nozzles.

Consumers shopping in the $40-50 price range are likely to seek earphones primarily for casual listening rather than for critical audiophile use.

Recognizing this, the seasoned KEFINE team opted for a sound profile that promotes smooth and enjoyable listening experiences, catering to the preferences of the majority.

In a departure from typical practices, they maintained a balanced tuning that avoids extreme frequency responses. The Klean features a gentle bass emphasis with commendable sub-bass extension, present mids, and a smooth yet clear treble.

The overall sound signature strikes a balance, neither overly V-shaped nor U-shaped, while emphasizing the significance of the mid-range without excessive focus on either the bass or treble.

The KEFINE Klean is a versatile earphone that performs admirably across various music genres, appealing to a broad audience, with the exception of those seeking a specialized or highly technical audio experience.

The treble response of the Klean is characterized by a smooth and unobtrusive quality, which some may perceive as lacking vibrancy; however, it remains impressively clear and well-articulated. It strikes a balance between lightness and sparkle, preventing a dark tonal character while avoiding excessive sharpness or brightness. The timbre is natural enough, though it may exhibit a slight metallic quality, particularly with higher-pitched orchestral instruments.

In terms of detail retrieval and overall resolution, the Klean performs satisfactorily within its category, though it does not offer significant depth or exceptional analytical capabilities. While it may not be the most technically sophisticated option, it makes up for this with its inherently musical character.

The mid-range exhibits a well-balanced tuning, characterized by a lack of significant recession or excessive brilliance in the upper mid-range. This results in a neutral sound profile that is pleasant to the ear, minimizing the risk of listening fatigue.

The clarity and articulation are very good, free from the masking effects often associated with mid-bass bloat. With its vibrant and harmonious tonal variety, the Klean effectively engages the listener with their preferred music.

The thoughtfully accentuated bass enhances the listening experience across various musical genres, remaining sufficiently in tune for more discerning listening, provided one is aware of its limitations.

Its technical performance is competitive; the bass is quick, well-defined, and controlled, featuring moderately rich textures that are not overly lean. While the Klean may not deliver extreme punchiness or impact, it still offers a satisfying dynamic range.

The soundstage is somewhat narrow and lacks significant depth; however, it provides adequate space and reasonable imaging, allowing the listener to perceive the intricacies of the music without descending into a messy sound experience.



With the black nozzles

The black tips enhance the upper mid-range and treble frequencies, while subtly reducing the bass, resulting in a more vibrant sound profile for the Klean. This configuration allows the Klean to produce a clearer and more brilliant sound without becoming harsh or piercing. Additionally, the bass achieves greater tonal precision while maintaining its rich and dynamic quality.



Comparison with the KEFINE Delci

The KEFINE Delci is priced at $10 above the Klean, leading some to question whether the additional expenditure for the Delci is justified.

The response to this inquiry is straightforward: the Delci offers a warmer and more relaxed sound profile compared to the Klean, featuring a treble that is less airy and sparkly. However, there are additional qualities that warrant the extra $10 for those who prefer this tonal balance. The Delci provides greater resolution, delivering a more expansive sound than its counterpart, along with a wider soundstage and a bass response that is both punchier and more technically refined.



Conclusion

The Klean serves as further evidence that KEFINE possesses a remarkable ability to produce earphones that appeal to a wide audience while maintaining affordability.

The KEFINE Klean is constructed with superior craftsmanship and delivers sound quality that exceeds expectations for its price point, positioning it as an excellent entry-level choice and a genuine value in a highly competitive market.

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The review sample was kindly provided free of charge in exchange for an honest review. I don't use affiliate links. The price of the KEFINE Klean is $49 and you can buy it from Linsoul.

Disclaimer: For various Google indexing reasons, most parts of this review have been processed with an automatic paragraph rewriting tool. However it reads exactly the same as the original content that is available in my website.

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Disclaimer:​

Thanks Kefine for sending Klean as a review unit. They didn't provide me anything to influence this product. I will be unbiased and share my thought about Kefine Klean

I would like to mention one more thing:This review is based on my personal music preference and sources cause music preference varies person to person and sources

If you want to buy one of this visit
https://www.amazon.com/dp/B0DK4WR4FJ/kefine+klean/?tag=headfi-20&th=1
https://www.aliexpress.com/item/1005007957993609.html?dp=2458032497&af=32858&aff_fcid=6ac2254075cd4a0393365ccb87537b3c-1738428517551-08716-_Dc7G5vh&tt=CPS_NORMAL&aff_fsk=_Dc7G5vh&aff_platform=portals-tool&sk=_Dc7G5vh&aff_trace_key=6ac2254075cd4a0393365ccb87537b3c-1738428517551-08716-_Dc7G5vh&terminal_id=79ea47c9cdd44614b76768305164cb1a&afSmartRedirect=y&gatewayAdapt=4itemAdapt
https://hifigo.com/products/kefine-klean
or you are from Bangladesh
https://geekmartbd.com/

Specifications:​

MODEL: KEFINE KLEAN
IMPEDANCE: 32Ω
SENSITIVITY: 107dB
FREQUENCY RESPONSE: 20Hz - 20kHz
CABLE LENGTH: 1.2m
PIN TYPE: 0.78mm 2-PIN CONNECTOR
PLUG TYPE: 3.5mm
DRIVER UNIT(S): 1 DYNAMIC DRIVER

Unboxing Expirence:​

The unboxing expirence of klean is very simple . In the box you will have the iems, a 3.5 mm cable, a hard carrying pouch, two types of tuning preference nozzle and some eartips.

Introduction:​

Ok.. I thing I'm quite late for review of klean but at a time klean doesn't or may not disappear upcoming time . Cz the sound, value it offers is quite hard to beat . Klean is the first product for me from Kefine their other product like delci , klanner wasn't type of mine preference. But klean was a totally different experience for me which I'm gonna share later in my review

Pairing:​

Usually I don't test any IEM in just stock form I always do swaping cable, tips rolling , matching source to get the best outcome. When I was testing Klean my favorite pairing was cable : Dunu lyra mini
Tips : Dunu Candy

Cable:​

Stock
Dunu lyra mini

Eartips:​

Dunu Candy
Divenus Velvet

Sources:​

Dongle:
Ibasso Dc04 Pro
Ibasso Dc Elite
Cayin RU7
Ddhifi tc44Pro E2
DAP:
Cayin N3 Ultra
Ibasso DX180

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Build and Design:​

These Kefine Klean IEMs are made of solid metal alloy construction, making them both durable and good looking. Further, the design is pretty minimalist but manages to look elegant with well-crafted faceplates and compact form factor. The interchangeable nozzles definitely add a layer of customization for user preference. The cable is sturdy and tangle resistant and has minimal microphonics, further contributing to the user experience.

Fit and Comfort:​

Despite their metal build, the Klean IEMs are designed for comfort. The ergonomic shape ensures a secure fit, accommodating various ear sizes without causing discomfort during extended listening sessions. The weight is balanced, and the angular design aids in achieving a good seal, which is crucial for optimal sound quality and noise isolation. Users have reported that the Klean provides better isolation and comfort compared to some competitors, making them suitable for prolonged use.

Tuning nozzle:​

Kefine Klean offers two nozzles in the box one is Silver and another one is Black. Difference between them maybe not huge but they are quite noticeable .

Black Nozzle: ​

The Klean, once fitted with a black nozzle, will sound brighter with emphasis on treble, making the sound more detailed and crisp. Furthermore, this also has been stated by some people to introduce a slight sibilance to the sound, in which the hisses at high frequency are stressed.

Silver nozzle: ​

Warmer and more even in sound profile, this presents the audiophile's dream of richness and coherence. It focuses on milky rhythm presentation with pleasant note weight, thus cleaning up for the heavier low-end frequency presentation; it is more adept at those who will look for a more laid-back presentation with the music being upbeat.

Note: this review is based on Silver nozzle

Sound Quality ​

Sub-bass :​

The Klean has a satisfying sub-bass presentation, digging deep to give that palpable rumble which complements genres such as electronic and hip-hop well. The low-end is all about the sub-bass; it's a hard-lined attack with a fast thud approach that makes the bass engaging at this price point. It isn't the most dominant, but it provides a solid foundation in the overall sound without overwhelming other frequencies. This balance ensures that tracks with pronounced low-end elements are rendered with both power and clarity, offering listeners an immersive experience.

Mid-bass :​

On the mid-bass, Klean keeps up a strong, controlled presence.Bass guitars and kick drums come through authoritative to provide a full-bodied, thick sound that remains tight and refined. The mid-bass is less elevated than the sub-bass but is still pretty impactful to make sure the bass doesn't sound too forward or overpowering in the mix. That way, the bass response will be fun and engaging without sacrificing clarity or detail in the midrange.

Male Vocals : ​

Male vocals on the Klean sound clear and warm. The very slightly warm nature of the mids makes the male voices natural and intimate yet never honky or shouty. The balance here is nothing short of amazing, since it lets the vocals be on top without overwriting everything in the mix. This results in a very smooth and enjoyable listen, especially in genres with a strong focus on vocals.

Female Vocals :​

The clean and slightly forward upper mids on the Klean help the female vocals. Tuning here is done so that the female voices come through clear and detailed yet not sharp or sibilant. Natural and lively upper frequencies create an engaging and real-life-like female vocal portrayal, full of expressiveness and emotional resonance.

Instrument Separation :​

The Klean is commendable for instrument separation, given its price. It is easy to tell which instrument is playing at any moment in a complicated track, and each element has its own space without sounding congested. This clarity ensures that intricate musical passages are rendered with precision, allowing for an immersive and detailed listening experience.

Soundstage and Imaging :​

The soundstage of the Klean is medium-sized, neither too cramped nor too wide. Imaging is quite good and allows the listener to place instruments with a good sense of their shapes and directions. This capability adds to the overall immersive quality of the listening experience, making the Klean a compelling choice for those seeking both accuracy and engagement in their audio.

Testing Tracks:​

Anchor - Novo Amor
A Thousand Years - Christina Perri
Back In Black - AC-DC
Billie Jean - Michael Jackson
Bohemian Rhapsody - Queens
Careless Whisper - George Michael
Darling Pretty - Mark Knopfler
Gangster Paradise - Coolio
Get Lucky- Daft Punk
Happy Nations- Ace of Base
Imagine- Jhon Lennon
Immigrant Song- Led Zeppelin
Just The Two of Us- Grover Washington Jr.
Kiss From A Rose - Seal
Kill Jill- Big Boi
Let Her Go - Passenger
Lose Yourself to Dance- Daft Punk
Moby Dick- Led Zeppelin
Pale Blue Dot - Dream Theater
Playing God- Polyphia
Portable Door - Deep Perple
Power of Love- Laura Branigan
Pretty Little Thing- Michael Jackson
Stand By Me- Ben E. King

Finally, in this fast changing market nothing stays for long but I believe that in 2025 Klean will also compete with others . And if somebody ask me is it worth after all these month I will say yes it worths every penny for its mature sound, excellent build and fit .

That was my thoughts about Kefine Klean. Let me know your thought about this IEM Till then keep listening .

Introduction​

Kefine has been one of the more successful IEM makers of the last couple of years. I reviewed Delci and praised it for its lifelike timbre and enjoyable tuning. Klean is the latest release from Kefine that pulled down the price more while offering two different tuning nozzles. Coming at 49$, Klean looks like it offers a better value but does it really?

Disclaimers​

Kefine Klean was provided to me by Kefine for free. As I always say, everyone is biased one way or another, so take everything you read with a grain of salt. Additionally, I will try to be more concise and to the point in my reviews from now on, without worrying about word count. If you have any questions, please ask me in the comments, and I will try to answer them to the best of my abilities.

Packaging, Build and Accessories of Kefine Klean​

Klean comes in a smaller and more compact packaging than its bigger brothers, which isn’t exactly a downgrade since it comes with pretty much the same accessories. Carrying case this time is covered with fabric instead of faux leather. Cable that’s provided with the IEMs is again different but similar in thickness and behavior which is quite manageable. Only single ended termination is available but at this price it’s not really a con.



3 pairs of generic eartips come out of the package as usual along with tuning filters for the nozzles. Interestingly nozzles aren't screwed out completely like other IEMs like Moondrop Kato, Kadenz or Simgot EA500, EA1000 and the like. Instead only filter parts can be removed and replaced, similar to AKG N5005. It might have reduced the costs and resulted in the very affordable price of Klean but only time will tell if it’s durable or not.

Earpieces themselves are made out of metal and stay comfortably in my ears. Shape is pretty much the same with the Delci however, probably due to the painting, Delci looked more premium as it should considering the price.

Sound of Kefine Klean​

I used mostly the silver filters in my testing. Compared to the silver filters, the black filters sound more detailed but also leaner and more intense. The tonal balance that silver filters presented suited me more.

Tonality​

Klean has a slightly warm and pleasing tonality that somehow can still sound relatively clean so Klean name isn’t just there for the sake of it.

Bass on the Klean is elevated but not overbearing. In terms of the quality however, I can’t say it’s top notch. Maybe I’m spoiled with the bass of higher quality gear but couldn’t get the impact I got used to from Klean. Let’s say I have heard tighter, more impactful and satisfying bass in this price range and leave it at that.



Klean’s mids sound pretty much on point. Overall slightly warm and pleasing. Probably trade-off at the bass improves clarity of mids so vocals sound clean, intimate yet not honky, shouty or overbearing. The balance struck here is exceptional.

Treble rendition of Klean safe to say the least. It doesn’t have any erratic peaks that would sound harsh or piercing but I can say there is a slight unevenness that can throw off the timbre occasionally. It might be because of the fit and others might not notice it but to my ears Klean doesn’t have the most even or smooth treble.

Technicalities​

Klean isn’t exactly an overachiever when it comes to technical ability. It has a moderate sound stage size. Resolving capability is also average for its price but imaging is surprisingly good. I couldn’t not only pinpoint the locations of the instruments but also I could almost tell their shapes and directions.

Comparisons​

Kefine Klean vs. Kefine Delci​

• Delci has a little more impactful and rumbly bass. Klean’s bass is sloppy and boomy compared to that.
• Delci is warmer in the lower mids, Klean sounds a little bit cleaner.
• Klean is slightly tidier and more relaxed in the lower treble but more zingy in the upper treble.
• Delci sounds more natural to my ears in terms of timbre however it fits more snugly in my ears which might be affecting my perception.
• Delci is slightly more detailed but they aren’t really that far apart. Delci’s soundstage is wider and deeper, however imaging on Klean is somehow more precise.

Kefine Klean vs. EPZ Q5 Pro​

• Q5 Pro has a better fit and comfort in my ears.
• One doesn’t sound particularly bassier than the other however, Q5 Pro has a deeper, more tactile and satisfying bass. Klean’s bass sounds a little pillowy compared to Q5 Pro.
• Both have slightly warm and rather forward mids but Q5 Pro sounds even more forward and shoutier.
• Q5 Pro is brighter while Klean sounds more neutral and natural. While the Q5 Pro has a more elevated upper mids and treble, it still sounds smooth, probably because of the fit. It fits more snugly in my ears so treble peaks are pushed above the sibilance region (mostly between 6k and 8k).
• Technically, the Q5 Pro is mostly superior to the Klean, It sounds more open, spacious and airy. Klean’s stage is rather moderate. Q5 Pro is also a more resolving pair of earphones. Klean sounds a little blunted compared to Q5 Pro. Imaging and layering however, feel more precise on Klean. I could almost feel the shapes of the objects even though they felt closer than I’m used to.

Kefine Klean vs. RG15 (Analog)​

• RG15 sounds much warmer, thicker and has a boomier and more powerful bass. RG15 also extends deeper into the subbass. Klean, as the name suggests, sounds cleaner and more natural.
• RG15 has an unapologetic V-Shaped tuning. Mids are recessed but upper mids and lower treble are elevated so it sounds a little shouty and borderline sibilant. Klean on the other hand sounds very natural and on point. It has a nice intimacy without getting honky, shouty or too personal.
• Klean has just enough treble energy. Cymbals and hi-hat attacks are there but they lack some bite and splash that I like. RG15 might look too aggressive in the graphs when it comes to treble but it actually sounds pretty good. It really depends on the taste but overall Klean sounds more natural and safe while RG15 sounds brighter and more exciting.
• RG15 has a more capable driver and it actually feels faster and more effortless however due to its tuning, masking is unavoidable therefore some details get lost in the mix. Klean reveals details more evenly. Klean also has a more lifelike timbre. Klean’s soundstage is slightly wider but RG15 has a much deeper soundstage. Klean’s imaging and layering capability also feels superior. In terms of technical capabilities, it’s a fight between superior tuning and better drivers.

Conclusion​

Kefine has another winner in their hands. With a great metal build and comfortable fit at only 49$ it’s hard to find a fault really. It has an inoffensive pleasing tonality that goes with a wide variety of genres. For me it lacks the last bit of magic to be one of my top IEMs but I can still recommend it without hesitation. Looks like other reviewers liked it even more than me so check them out as well and if you are interested, some non-affiliated purchase links are below.

Amazon US:

https://www.amazon.com/dp/B0DK4WR4FJ/kefine+klean/

HiFiGo:

https://hifigo.com/products/kefine-klean

Aliexpress：

Hifigo: https://www.aliexpress.com/item/3256807735705434.html

Kefine: https://www.aliexpress.com/store/1103187464/pages/all-items.html

Disclaimer​

First of all, a big thank you to Kefine for providing this review unit, which made this review possible. As always, I’ll be sharing my honest and real-life experience with this product. I hope my review gives you a clear picture of both the strengths and weaknesses of this IEM, helping you decide if it’s the right fit for you.

If you’re interested in purchasing it, here are some links to check out:

Amazon US:

HiFiGo:

Kefine Aliexpress:

For those in Bangladesh, you’re in luck! The Kefine Klean is now available at Geek Mart. You can even visit their store to test it out in person before buying, which I think is an amazing opportunity to experience it firsthand.

I sincerely hope this review helps you in making a confident decision. Feel free to share your thoughts or ask any questions. At the end of the day, it’s all about finding the right gear that fits your needs.

Build Quality and Design​

For the price, the build quality for the Kefine Klean is a real treat. A fully metal build just screams premium quality when picked up. To this day, very few IEMs under the mark of $50 came out as refined as this one. Kefine truly appears to have held nothing back on giving their absolute best here. The brass nozzle adds a touch of durability, but one should know that if not well taken care of, it may oxidize over time and hence cause discoloration. While oxidation may occur, it’s primarily an aesthetic issue and doesn’t impact performance.As for the design, it’s simple yet elegant. The black finish is sleek and feels durable enough to resist chipping or fading with regular use.

Fit and Comfort​

In terms of fit, the Klean does a great job—not too big, not too small—so most people won’t have any trouble, but I personally didn’t have any issues with the fit; it was rather ergonomic in my ears and felt secure. The weak link here is the stock tips, which may become uncomfortable over longer periods. Upgrading these to a better pair will be highly recommended to maximize an exceptional performance; out of the box, tips have mediocre quality. When it becomes paired with good-quality tips, the Klean gets comfortable for long sessions. Additionally, both nozzle sizes and thickness are spot-on as there is no excessive tension but never too loose. It comfortably pushes to excellent with the perfect pair of tips.

Cable and Tips​

The price of the Kefine Klean justifies having a decently made cable. The cable consists of silver-plated copper material with 2 cores featuring 18 wires per strand, 3 strands per core giving a total of 108 wires. This high-quality thick cable assists in providing a clean transparent sound, and the material extends the treble for better clarity. The stock cable is more than capable of delivering great performance, so there’s no immediate need to upgrade. However, if you prefer a 4.4mm or any balanced termination, an aftermarket cable is a good option to consider because Klean only comes with 3.5mm (s.e).

Tips​

The stock tips, however, don’t quite unlock the full potential of the Klean. They’re not the most comfortable, and the sound doesn’t feel as dynamic as it could be. The bass response is reduced, and the treble can sound a bit sharp. However, with some better aftermarket tips, like the Final E clear or Dunu Candy, things get significantly better. With such tips, the Klean’s sound becomes tighter and more controlled; the bass improves, the vocals get more even, and the treble smooths out for a much more refined listen. For the best sound, upgrading the tips is definitely recommended.

Tuning Nozzle​

One of the standout features of the Kefine Klean is its two tuning filters—Silver and Black—that allow you to tailor the sound to your preferences. These filters aren’t just for show; they genuinely impact the sound signature.

Silver Filter

The silver filter comes pre-installed, and honestly, it’s my favorite of the two. The treble feels perfectly balanced: airy and energetic without being overwhelming.Vocals sound smoother and more refined, with no harshness, making it ideal for extended listening sessions. The bass also feels tighter and more controlled, contributing to an overall balanced sound signature. This filter is all about refinement and balance—it’s simply a joy to listen to.

Black Filter

The black filter, on the other hand, brings a different vibe. It injects more energy into the sound, particularly in the vocals, making them feel more forward and lively. This can be fantastic for high-energy tracks, but there are trade-offs. The added energy slightly reduces the bass impact, and the treble can lean toward brightness, occasionally becoming sharp on some tracks. Vocals are more vivid but might feel aggressive for those with sensitive ears.

Which One to Choose?

Both filters shine in their own way. If you prefer a smoother, more balanced listening experience that you can enjoy for hours without fatigue, the silver filter is the way to go. Meanwhile, the black filter is better for those who love energetic, punchy sound with a touch of extra treble sparkle. Personally, I find myself gravitating toward the silver filter because of its natural and cohesive sound. But the flexibility to switch between the two is a fantastic feature, letting you adapt to different moods and genres.

Pouch​

practical and pocketable

Testing Source​

• Cowon Plenue R2
• Astell & kern SP1000M
• Cayin N3 Ultra
• Ibasso DX180
• Hiby R3 ii
• Ibasso DC Elite
• Cayin ru7
• Questyle M15
• ONIX Alpha Xl 1
• Ddhifi TC44 PRO E2
• Epz Tp35
• Epz Tp20 pro
• Moondrop Dawn Pro

Cable

Stock cable and Dunu lyre Mini

Tips

Dunu candy , Final clear ( Pink ), Divines Velvet

Bass performance​

Sub-Bass​

The bass extension in the Klean is very impressive, reaching deep down into the lower frequencies. The rumble is satisfying and there, which makes for a rich and immersive listen, especially in most genres like hip-hop. A track like Angel by Massive Attack really brings this out-you can feel the sub-bass come alive without overpowering the rest of the mix.

Most striking is how controlled it is, sub-bass stays clean and defined without bleeding into midrange; that, in turn, speaks for clarity and separation, even on tracks that really hammer the bass, but one could say that the physical presence of the sub-bass-that “thump” that bass heads go for-is somewhat understated. If the overwhelming impact of the bass is what you’re looking for, you may leave wanting. That said, for those who are looking for a more neutral and balanced tuning, the sub-bass performance is nothing short of excellent.

Mid-Bass​

That’s where the Kefine Klean shines: the mid-bass is tight, punchy, and ridiculously well-controlled. Each kick drum hits with spot-on accuracy, and the bass notes are clean and separated, even in the most complicated tracks. Take Ticks & Leeches by TOOL, for example—the Klean tackles the rapid-fire basswork with ease, putting in a dynamic and engaging performance.

This mid-bass is very versatile, especially for genres like rock and instrumental music, as it provides great speed and strong impact. Even in layered tracks containing a bassline, there is no hint of muddiness or congestion. It has that perfect amount of energy to make you feel the rhythm without drowning the other elements in the sound.

Mid-Range​

Male Vocals​

The male vocals on the Klean sound rich, full-bodied, with a natural weight and warmth to the presentation, making them sound very organic in nature. For instance, Gregory Porter’s Musical Genocide sounds great here; his deep, soulful voice is rendered with good clarity and presence. The Klean does not shy away from painting the finer details of male vocals and gives them a natural, ground-like intimacy without introducing artificial coloration.

Female Vocals​

The Klean also impresses with female voices: clear, energetic, and detailed. Tracks like My Heart Will Go On by Celine Dion present it with no issues regarding higher-pitched female voices. There is excellent clarity and liveliness in Celine’s voice, with no harshness or sharp edges that can make listening fatiguing. The “sss” and “shh” sounds are smooth and refined, quite remarkable for an IEM in this range.

Midrange Instruments​

Midrange instruments are equally pleasant to listen to. The bass instruments on Gregory Porter’s song, the swooping melodies of pop ballads-all come through with the Klean making sure every detail is audible. Natural timbre is conveyed without even the slightest hint of harshness, even when listening for hours on end.

One of the striking things with the midrange is just how non-fatiguing it is. With no sharpness or harsh peaks, you can easily consider doing very long listening sessions with absolutely no discomfort, and that will make the Klean a reliable choice for extended use.

The Treble​

The treble performance of the Kefine Klean sounds as clean and clear as its name can lead you to feel. The treble extends decently, providing an airy and open sound that gives the music room to breathe, adding a sense of space to the overall presentation. For its price, the Klein is impressive in delivering good micro details; subtle nuances come through with the music.

While the treble is slightly energetic, it retains its smooth and non-fatiguing character. There’s no sharpness or harshness in the upper frequencies, making them even-handed to provide long comfortable listening. This makes it ideal for detailed and intricate tracks.

Speaking of the string instruments, the Klean copes excellently with them. For example, Clair de Lune by Debussy—its treble presents strings naturally and vividly, catching their delicacy without artificial brightness.

Take Five by Joe Morello would be perfect for high-end reference. The cymbals and higher frequencies are quite clear, great in texture, never sounding forward or sharp. Treble is smooth but keeps the required energy and air to make music alive.

Technical Performance​

Soundstage​

One of the first things that came to mind upon listening to the Klean – it’s spacious. It gives music room to breathe, and while not as wide as some of the more high-end IEMs out there, for what it costs, it does a stellar job. Play something like “Layla (Live)” by Eric Clapton, and you’ll notice how it captures that “live concert” feel. The instruments and vocals spread out just enough to make you feel like a part of the crowd. The instruments and vocals spread out just enough to have you feel like a part of the crowd. It’s not super wide, but precise enough to make things natural and immersive.

Imaging​

it’s here where Klean really shines. Imaging is sharp and concise. Each and every instrument and vocal comes across as being placed exactly where it should be. Just listen to “Bubbles” by Yosi Horikawa, and you should know exactly what I am talking about; It’s like assembling a sound puzzle, where every element fits perfectly into place. It doesn’t matter whether it is a clear voice in the fore or subtle background details that fade away; with Klean finding all those minute elements to create a more realistic listening experience was way easier.

Separation of Instruments​

If from the very outset, there has been one thing that Klean could do supremely well, it is to make everything clear and separate. Even when the songs have frenetic, multi-layer arrangements, it can still avoid any muddiness. Take, as an example, the chaotic instrument-filled track “Cha Cha Bonita” by Charly Antolini. The Klean handles it marvelously. Every struck drum, crashing cymbal, and blaring bass note comes through crystal clear. If you are into genres like jazz, classical, or progressive rock, this degree of separation will make all the difference; you’ll pick up on things you might have never heard with other IEMs.

Conclusion​

If you’re someone who appreciates a neutral, balanced sound and you’re on a budget, the Kefine Klean might just be the right choice for you. It delivers a clean and detailed listening experience, with a satisfying bass response, natural mids, and airy treble that bring out the finer details in your music.

However, to truly make the most of its performance, a good pair of ear tips is essential. Something like the Dunu Candy, Final Clear, or Velvet tips can enhance the overall sound presentation, providing a better seal and a more immersive experience.

In short, the Kefine Klean is an IEM that offers solid performance for its price, especially if you’re into neutral tuning and enjoy clear, refined audio. It’s not flashy or overly exaggerated—it’s simply a reliable option for those who value sound quality and detail. If that’s what you’re after, this IEM is worth considering.

★ Introduction :-

Kefine is a newly established Chinese audio company, they have created a good hype in the current market by releasing their products. Kefine klanar was the first item in their IEM line-up. It was quite popular in the sub 100$ range and to maintain that consistency they later came out with some more affordable sets. I received their new entry level set "klean" a few week ago. Klean is the first set of Kefine offerings that I have used so far. In the current market, this single dd IEM is available at a very lookrative price (sub 50$). I have been using this set regularly for quite a few weeks. So, today I'll mainly try to represent my complete experience about it and also try to clarify how equitable is it at similar budget contenders.

★ Disclaimer :-

First of all, I would like to thank Kefine audio for sending me this review sample. I had no financial agreement with them to promote their product. So the entire opinion of this review is completely my personal.

★ Box Content at a Glance :-

This klean comes with a small looking white color box. Out of the box you will get a pair of IEMs, nice looking practical case, decent stock cable with single end termination, extra tuning nozzle, some generic eartips and extra paperwork.The packaging of this entry budget IEM surprised me. Because Kefine Audio has provided all the necessary accessories in this IEM box, so there is no need to buy anything extra. It can be said that Kefine has no place to complain here.

1. A pair of Kefine klean IEM × 1
2. A carrying case ×1
3. interchangeable nozzles ×1pair
4. 3 pairs Black eartip in size L/M/S
5. User manual ×1
6. Qc certificate ×1

★ Specifications :-

★ Design, Build Quality & Comfort :-

I personally wasn’t any fan like this design language of the klean.The design like small groove across the faceplate of both the black shells right in the middle of it, where the branding of Kefine has been highlighted in white color. When you hold these two shells, you get a solid feel from them.Two complete shells are made up of full aluminum alloy chassis with high quality machining.Which is capable of providing good fit and comfort along with durability. However, it is good to say that the stock eartips were not very satisfactory. They were of average quality, so tip rolling must be done for proper seal & comfort. I got better results using final e series tips on it.
But the most interesting feature of this IEM is its interchangeable tuning nozzle filter which plays a very effective role in the sound.Having an IEM in such a price range with a modular tuning nozzle can be considered a big advantage even though it was really effective.
Moreover, it has detachable cable system consisting of 2pin 0.78mm connector with single end terminated gold plated jack, quality wise decent silver plated copper cable is provided with the IEM. The stock cable doesn't create much microphonics during usage but is likely to oxidize in long run. Apart from that the quality of the carrying case is quite good and there was decent space inside to hold the IEM and the case seems to be enough to keep it safe. It is clear here that Kefine has tried to make their set klean almost ideal.

★ Sound Aspect :-

Klean is basically a set of U shape sound profiles where the bass and treble have a decent contribution and the mids are naturally pushed back a little more.The entire sound frequency is handled by the 10mm dynamic driver inside the Klean and the good thing is that there are no coherence issues to be found in the sound.There are two interchangeable tuning nozzles that make a noticeable difference in sound.Two nozzles respectively black & gold have been able to the complete experience of almost all types of listeners. The detail retrieval in the black nozzle is better compared to the gold one, but even if the detail falls in the golden one, it is possible to get a very engaging experience from here. This swappable tuning system of Klean lends it a really versatile character in this budget I must say.

★ Gear used :-

1. Questyle Audio Engineering CMA Fifteen
2 . Xduoo xd05 bal 2 (Se & Bal both)
3 . Cayin Ru7 (Se & Bal both)
4 .Questyle m15 (Se & Bal both)
5 . Quloos Mc01 (SE & Bal both)
6 . Epz Tp50 (Se & Bal both)
7 . Fosi Audio Ds1 (Se & Bal both)
8 . Fosi Audio Ds2 ~ 2024 (Se & Bal both)
9 . Roseselsa Rs9039 (Se & Bal both)
10 . Ddhifi Tc44Pro E2 (Bal only)
11 . Tempotec Sonata Bhd Pro
12.Blon V1 (Se & Bal both)

Kefine klean is a set of 32Ω impedance whose sensitivity level is 107dB, so not very powerful amplification is needed to drive it, I got decent loudness from the phone's 3.5mm port, but if a good quality dac amp or portable player is used, then it gets scaled up with the sources (neutral-warm)and becomes better sounding. However, the best pairing I've found with CMA Fifteen.Slightly improve stage depth & dynamics, better imaging even a bit more enhanced micro detailing capability and a little bit more polished tonal balancing.

Now, I will discuss the sound in detail, I will start with the Low end of this set, i.e. the bass....

★ The Bass :-

Klean has created quite a fun factor in the bass section, especially the sub bass can be attributed to this. Even after having a slight sub bass (20-60Hz) boost, I didn’t notice any bloated issues there so deep & rumbly sub bass presence could be felt very well with sufficient texture. On the other hand, the mid bass is a bit disappointing due to its lack of sufficient impact & depth. As a result fullness is not found in bass guitars, kick drums and other low-end instruments but the deficiency remains there.That's why the absence of fast attack & decay of bass in genres like rock or metal will cause some suffering in the case of bass head folks, although if you switch to its golden nozzle, then the bass notes seem a little more denser, but it's definitely not that bass head level.

★ The Mids :-

In the context of midrange, it is basically upper mids focused. Due to which moderately clean & slightly forward presentation is available from upper mids. Lower mids have slight recession which is normal from this type of tuning. As I said earlier about its tuning nozzles which also affected the mids section. When moved to the black nozzle, the upper mids region is slightly brighter, which makes the 2k-3k area seem a bit more energetic. Which gives some female vocal make a bit shouty & unnatural feeling. But male vocals can be said to be more or less on the good side. On the other hand, moving into the gold nozzle that creates a opposite scenario, You have to sacrifice a little more on the mids clarity & texure with the minimal bleed of the sub bass makes the lower mids warmer but overall it adds more thickness to the vocals body which sounds quite soothing & more enjoyable.

★ The Treble :-

The treble section was clean & crisp which lent extra bytes to the string instruments.Treble does not seem very mature but I did not notice much lack of detail retrieval. But the upper treble on the black nozzle seemed to be forward and bright, and there was more sparkle presence which is not natural.There is a bit of piercing or sibilant even the high-pitched sound seems to be pushed a bit more for many. Besides, treble extension is very good from this nozzle. But if shifted to gold nozzle, the airiness is lost in the area after 10k and the whole treble section is smoothed and the detail is reduced noticeably.This thing can be considered more safe tuned by many people who prefer more treble. In my opinion, long listening season will be ideal with this one specially for treble sensitive folks. Although upper treble energy-sparkle & detail have to be compromised which may be preferred if not bothered.

★ Technicalities :-

Technically pretty good but it suits with the black nozzle. Sound stage height was slightly better than average and width was also on the good side.But the stage lacked a bit of depth, which needed to be better. Due to its good imaging capability, the positioning of the instruments can be potrayed fairly well and at the same time there is no complaint about the stereo presentation.Detail retrieval wise it performs well but it is good to say that the excess of micro detail presence was mediocre level and macro detail was largely lacking. Tonality & timbrel accuracy was just average. As a single dd I expected some better from here. I have already said that its imaging capability is good, despite that is not able to satisfy everyone in gaming because the upper registers sound is a bit too bright-ish on its black nozzle, so if you play any battle royal type games, then gun shots sound seems a bit aggressive, which is important to keep in mind. Again, if switching from black to golden nozzle, then this set lags behind in resulation and overall technical ability.

Overall rating out of 5 is what I would give

Bass : 3.5 /5
Mids : 3.8/5
Treble : 4/5
Technicalities : 4/5
Dynamics & speed : 3.8/5
Build & Aesthetics : 3.5/5

★ Comparisons :-

~Kefine Klean vs Celest Ignitex Beast~

Ignite beast's lower treble was a little bit more detailed for it's hybrid driver setup even its warmer and thicker than klean along with vocals.Celest beast has timbrel issue and tonal accuracy wasn’t so impressive. It is almost the same in both sets but many may face problems due to pressure build up in the beast which can be called the most ideal aspect of klean in terms of comfort. Both sets are sub bass focused but the bass notes of the beast seems slightly denser although klean's swappable tuning nozzle system makes it more versatile. Also the sound notes delivery of klean is on the faster side. However, there is no difference in sound stage height, but depth & width condition is better on Kefine's offering. On the other hand, the imaging capability will easily beat the beast's behind for the klean precise instrument placement capability with better micro detailing presentation.

~Kefine Klean vs Roseselsa Aurora Ultra~

Aurora ultra is another new entry budget offering in the near price category. Its most disappointing part is its build quality, on the other hand, Klean is in a much better position. In terms of stock accessories, aurora ultra offers better value but lags behind klean in terms of sound performance.Technicalities aurora ultra's big strength but in terms of detail retrieval & resolution can't beat Klean in any way. Regarding tonality & timber, none of them could shown amazing results. I personally found the aurora ultra's planar timbre more annoying also average treble clarity.I think Klean can be a good option in the current market scenario if these minor issues are excluded.



★ Conclusion :-

The sub 50$ price category has become quite competitive. Many chi-fi manufacturers have released their budget offerings in this price range. Kefine brand wanted to create a strong position in the market with their friendly offering from the beginning and in my opinion they have succeeded to a large extent.The Klean is their new entry level set, it has some strengths that put it ahead of its competitors in a similar price range. Klean can easily satisfy almost all types of listeners in terms of sound, especially for its tuning versatility. From my point of view it will be recommended to buy it if one has such a budget then this set will be a good option no doubt.



I've provided the purchase link below for everyone convenience

Hifigo official store (link isn’t affiliated)

KEFINE KLEAN: KEFINE really meant it as “CLEAN!”

KEFINE has launched a new budget iem , the KEFINE “Klean!”. And KEFINE has completely redeemed themselves with this Klean , which features a single dynamic driver and its priced at just 49.00$



NOTE

KEFINE sent this to my friends at Sonicmantra.org for review purposes. Huge thanks to KEFINE and the Sonic Mantra team. However, these are my honest opinions; I am not being paid or influenced in any way to say anything good or bad.

If you want to purchase this product you can order from KEFINE themselves or if you are from Bangladesh you can pre-order them from Geek Mart.

TESTED WITH

• Cayin N3 Ultra
• Cayin RU7
• ddHiFi TC44Pro E2
• Onix Alpha XI1
• iFi Hip Dac 2
• Fiio Btr7

SPECIFICATIONS

• Driver type: Dynamic driver
• Driver size: 10 mm
• Frequency response 20 Hz - 20KHz
• Sensitivity: 107 dB +/- 3 dB I
• Impedance: 32 Ω +/-15%
• Cable length: 1.2 M +/-0.2 M
• Plug type: 3.5mm SE
• Weight: 10g (Each side)

WHAT’S IN THE BOX

• Klean Iems
• Silver plated copper cable
• Tuning nozzle
• Ear tips
• Carrying Pouch

BUILD & DESIGN

The build on the Klean is absolutely solid and fantastic! The all metal build is something to praise as we don't see that very often in this price bracket and also the matte finish is also a big plus point. Design wise I personally like the minimal matte black with squared white boxed pattern on the faceplate with their branding on it and I think many will prefer this sort of minimal approach than a more colorful and funky one but that's totally personal choice at the end of the day.

FIT & COMFORT

Fit on them are really good due to their shell size and also its very ergonomic design. Even though the whole design has a hint of industrialized look to it , each and every edge is smoothened making it an ease to keep it in the ear. I don't think even people with quite small ears will have an issue regarding getting a good fit on them. And coming on to the comfort part , yes it did take some time for my ear to get used to the weight of it but then when it did , it became one of the most comfortable iems in this price bracket.

SOUND

The Klean is tuned with balanced sound in mind but it also comes with two tuning nozzles and they aren't something which barely make any difference , the difference it creates is actually quite significant and noticeable. The default one it comes with is the silver one which features a more controlled upper midrange and air region. Whereas on the black nozzle the upper midrange and air is more emphasized.

I personally felt like the black nozzle sounded a bit too much for me , a bit on the shouty side of things and fatiguing on longer periods of usage. Hence I stuck with the silver one and tested it based on that , whatever I’ll mention later on will be based on how it sounds on the silver nozzle.



BASS

Sub-bass section is very clean and quite rumbly but I expected it to be a bit more in terms of quantity, it nailed in terms of quality in this price range. Though it goes quite deep and is very controlled if it had a touch more quantity it would've been perfect in my opinion.

Mid-bass is where the Klean is truly exceptional , not only it has the quality but also the quantity too. Very tight and controlled hits and slams. Not only that it also has a great body to it. And moreover it doesn't bleed into the lower mids which some of the iem in this price range does. All in all , the mid-bass performance will surely satisfy a lot of people out there for sure.

MIDRANGE

Male vocals are on point , very natural and smooth with a hint of warmth in them. They are full bodied and lush. Though their placement in the mix is a bit laid back , not as upfront as many might want but I personally don't have an issue with this.

Female vocals a bit towards the laid back side. They are quite smooth and lively but a touch more energy would really make them quite more engaging to listen to . I personally prefer more energetic and upfront female vocals , hence i felt them to be less lively here also i felt like the vocals are a bit too over-bodied!

Instruments follow the same path as the female vocals , smooth and laid back , not upfront and lively as I personally would like them to be but then again many might prefer this sort of presentation and this excels in that. One more thing is that the instrument separation is also quite good for the price.

TREBLE

As the name implies , it's nothing short but "Clean". One of the cleanest treble sections out there in this price segment.
It's very smooth, has quite some sparkle and air to it but all in a laid back manner , this is the perfect treble section for people who want a smooth and slightly dark treble section.

But people who want a livelier, more airy and sparkly treble section can switch to the black nozzle and it will be good to go!

TECHNICALITIES

For the price of just 49.00$ it performs quite good , even better than some sets I've used which are priced closer to 100$ . Its not like it excels particularly in one section and average or below average in other sections. Rather it performs equally as good in every section.

SOUNDSTAGE & IMAGING

Soundstage wise it's pretty good , has a decent width and height to it . If i have to really nitpick it would be the depth section but then again looking at the price we can't expect any more from this.

Imaging is slightly above average , you can very easily pinpoint the instruments and even faint vocals without an issue!

DETAIL RETRIEVAL & LAYERING

Detail Retrieval is at its best for the price, it simply can't get any better than this while being this clean with this amount of detail.

Layering wise it's pretty good, identifying each layer was no issue at all , but then again due to its price it does have its limitations.

DYNAMICS & TRANSIENT RESPONSE

Dynamics wise it's really good , i didn't expect it to be this good but damn it really is that good!

Transient response is something that it does slightly above average in. Yes its quite fast and doesn't really feel slow or sluggish in very busy tracks.

CABLE & TIP ROLLING

I didn't feel like it needed a different cable, hence I tested it with the stock cable. But in terms of ear tips , I personally didn't like the stock one and this is one of those iems in which if you don't pair it with a good ear tip it sounds bad. In my testing I found that it sounds the best to me with the “Final E Clear” one. Would highly recommend this tip with this iem if you're looking for a balanced sound overall!

POWER & SYNERGY

Its quite an easy to drive iem , you can even run it of your phone (if it still has headphone jack!). I tried running it off my phone's jack , it ran just "fine" but running it of a phone wont give you its true nature.

A proper dac will help you get the true nature out this iem and yes with proper power and source , this iem scales quite a lot. Coming on the synergy part Id say a slight warm to neutral sounding source will be good for this , try avoiding any sort of bright sources for this!

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• 1DD Driver Configuration;
• Impedance: 32Ω;
• Sensitivity: 107dB;
• Frequency response range: 20Hz-20kHz;
• Connector: 2 pin 0.78mm.;
• Cable material: 2 core silver-plated copper cable;
• Price:49$.

• IEM itself;
• 2-core silver-plated copper cable, 1.2m length;
• 1 sets, 3 pairs of regular black eartips: (S / M / L);
• Interchangeable black nozzles;
• Carrying case;
• User manual and quality certificate.

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Separating, sound stage

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Kefine Klean vs Simgot EA500LM:


Kefine Klean vs BQEYZ Cloud:

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Disclaimer:

• I don’t read FR graphs. I only use my ears, as earphones should be used.
• Kefine sent this unit to me in an exchange for an honest, independent review. Rest assured that this review will do its best to devoid from any bias/es as much as possible.
• The following remarks and observations shall be made and owned only by me.
• No monetary compensation is/was involved before, during, and after the period of creation of this review.
• Your mileage may (and always, will) vary.

Burn-in time: 4-8 hours per day, 5 days.

Source/s used:

• - Non-HiFi smartphone (Infinix Note 12 G96), PC.
• - Tanchjim Space DAC
• - Fosi Audio SK02 USB DAC
• - Kiwi Ears Allegro Mini DAC
• - Aiwa XP-V710C CD Player (12 sec. EASS)
• - Sony Xperia X Compact
• - Local Files via Foobar, YouTube Music, Deezer, and Qobuz with UAPP.

IEM/Earbud/Setup configuration: Stock medium eartips, any form of EQ or MSEB off, 12-20% volume.

========================================================================
Sound signature:

• The Kefine Klean exhibits a “relatively or nearly balanced” sound signature, with a slight bias to the warmer side to my ears. If we’ll be specific, this may come across as a warm-v-shaped sounding set.

Lows:

• First things first, this will not be the IEM that will make the bassheads at heart (and at ears) groove to the beat. But don’t get me wrong, this does not lack any bass presence for most people. In fact, it is well-done for its price, in terms of its overall amount, quality, and control. This characteristic is evident on Ariana Grande’s “true story”, as an example, as its bass shows only when the bass hits on the track, and does not “stick” to the other parts of the track, particularly with vocals. It is subbass-dominant, leaning to the faster side of the decay, making things rumbly and literally “Klean”. Overall, the bass quality and quantity that the Kefine Klean has to offer is excellent to my standards for its asking price. But if I were to be critical, I prefer the midbass to be a bit more present, maybe within the same level of the subbass it has, adding a bit of punch and detail to the overall lows.

Mids:

• When it comes to the mids, it is again, “Klean”, literally. Like seriously, I personally love it that Kefine took the “Klean” name quite seriously and with dedication. There aren’t any perceivable midbass bleed in its lower mids despite it being slightly sounding laid-back or relaxed to my liking. Lower mids do not exhibit any form of added thickness, exhibiting a less coloured, nicely textured region. Upper mids are a bit elevated, exhibiting a very good amount of clarity, air, and sparkle. Peaks and mild harshness are a bit present on this region, and are much more audible when paired with the black tuning nozzle included. With that being said, people with ears that are very sensitive to brighter upper frequencies may want to look for something else, but I can confidently say that this isn’t a deal breaker, nor a problem for most ears.

Treble:

• Proceeding to the treble, this region is decently extended on both tuning nozzle filters, exhibiting a good amount of air, clarity, and sparkle. Cymbal crashes and splashes may come across as a bit much than usual for those people with sensitive ears, so do take note of that. Detail retrieval and resolution is excellent in my book for this asking price, as I can hear nuances easier than usual. Do take note however, that this IEM will not and will never try to present itself as an IEM that can be used for analytical listening.

Soundstage, Imaging and Separation:

• As for its technicalities, it is above average to my liking, if we’re talking under and within 80USD. The soundstage is decent in terms of width, height, and separation. It never came across as cramped or narrow to my ears, even on busy tracks. Separation and layering also shares the same character as it neatly presents things in a layered and clean manner. Imaging is precise and never had any problems on any scenario that I used it with, whether it be during calls or competitive gaming.

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Kefine Klean + Black Nozzle Tuning Filter in a Nutshell

• Overall, the sound became much more closer to neutral-bright to my ears. Everything sound firmer when compared, but in exchange for a brighter, more prone to fatiguing character. This also boosted the overall technical performance, particularly on its detail retrieval and soundstage.

========================================================================
Other IEM Comparisons!

Celest IgniteX Beast

• The Celest IgniteX Beast is slightly thicker, slightly slower, “less cohesive” sounding IEM when compared to the Kefine Klean, to my ears, at least. Mild BA timber are also present on the IgniteX Beast when compared, but has a “safer” overall character, when compared to the Kefine Klean, but not by a lot, in all honesty.

Simgot EW300 (Standard, Stock)

• The Simgot EW300 is a much thicker, more laidback, safer set when compared to the Kefine Klean. Some people may prefer the EW300 due to its warmer character, but some people will also find the Klean balancing the engaging and safer character, when compared to the EW300.

Simgot EW200

• The EW200 is definitely bright, wider, and leaner when compared to the Kefine Klean. It is also more prone to sibilance, and is slightly better on the technical performance, but not by a lot when compared to the Klean. The Kefine Klean makes up for it by being a more suitable all-rounder when compared to the EW200.

EPZ Q1 Pro

• The EPZ Q1 Pro is a more fun, Harman-sounding IEM when compared to the Klean, whereas the Kefine Klean aims for a more versatile and balanced approach. Upper frequencies are also a bit more unrefined on the Q1 Pro when compared.

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Pros:

• One of the “mature” sounding IEMs under 100 USD!
• Versatile, “nearly balanced” sound signature!
• Firm, clean, adequately thick bass response!
• Relatively clean, detailed mids!
• Decently extended treble response!
• Above average technical performance!
• Modular, well-crafted tuning nozzles!
• Excellent fit, comfort, and isolation!
• Solid, sturdy build and comfort!
• Very good quality of inclusions/accessories!
• Easy to drive!

Cons:

• Mild peaks and slight sibilance are present on sibilant prone tracks (black filter)
• Midbass could have a bit more punch and definition to my liking (subjective)
• An additional set of eartips would’ve been nice.

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Based on my personal experience, there aren't a lot of IEMs under and within the 60 USD that are as clean and as controlled as what the Kefine Klean does. Its overall firm, easy-handling yet relatively safe sound character makes it very remarkable for its asking price, not to mention its premium, durable, physical qualities. I am not overexaggerating or glazing by any means, but it is quite mind boggling to me that Kefine, a relatively new brand, achieved this level of refinement that other companies I’ve worked with, took months, or even years, to obtain. This is definitely a win for the consumers, particularly hobbyists as well, since they do not spend heaps of budget just to have a clean, mature sounding IEM. Hats off Kefine for being this Klean!

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Pairing recommendations:

• Source: The Kefine Klean is easy to drive. I do recommend any warm or neutral sounding DAC that has at least 2VRMS of output for an optimal experience.
• Eartips: The eartips included pairs well with this IEM, but you may still use your preferred eartips.
• Cable: The cable is simple yet elegant to my liking. You may always use your preferred eartips.

Thank you for reading!

Non-affiliated link here: https://www.kefineelec.com/en/ProductDetails.aspx?iProId=25

Additional Photos Here:

​

>>I am brazilian and I speak portuguese, so forgive my english, I’ll use translation tools to help<<


INTRO:

The first time I heard about KEFINE I thought: “here comes another new earphone company”… But, the company launched some earphones and everyone started talking good things about their products. So, here we are, me and KEFINE KLEAN, which will be my first experience with the brand.

The KEFINE KLEAN was sent by HIFIGO, one of the main distributors of KEFINE products, as well as several other brands and audio products. More information on the links below.

Price: $49.99 USD
Color: Black
Cable: Without Mic



HIFIGO LINKS:

https://s.click.aliexpress.com/e/_DeT9lLF



SPECIFICATIONS:

Single DD:

• (1) 10mm DLC Dynamic Driver (DD)

– Frequency: 20Hz – 20kHz
– Impedance: 32Ω ±15%
– Sensitivity: 107dB ±3dB
– Detachable nozzles (filters)
– Termination plug: 3.5mm (straight design)
– Connectors: 2pin 0.78mm (detachable)
– Cable size: 1.2m ±0.2m
– Cable: Silver plated copper
– Shell: Metal alloy
– IEM weight: 9.3g (one side)(without eartips)
– Cable weight: 17.4g
– Total weight (packaging, iems, etc): 170.8g
– Packaging size: 12.8cm [H] x 11cm [W] x 3.7cm [D]



UNBOXING:





PHYSICAL ASPECTS:

Disclaimer

• Huge thanks to HiFiGo for providing the opportunity for me to review the Kefine Klean by providing a review sample for me. I really do appreciate it. However, all thoughts and opinions are my own, and are not influenced in any way.
• Please take this review with only a grain of salt, as everyone's hearing, fit, and gears may differ, so our experience may be different.

Price(MSRP)

• $49.00

Ear tips

• Dunu S&S

Drivability

• Fairly easy to drive.

• Any decent, modern dongle DAC/Amp should be more than sufficient.

Packaging

• Kefine Klean.

• Storage case
  • Pretty decent case for the price.

• Ear tips
  • 3 pairs of ear tips

• High-purity silver-plated copper stock cable
  • One of the best stock cables in the price range imho.
  • Well braided, soft, and very comfortable.
  • Although not the thickest, I think it is more than enough to be comfortable and sturdy.
• 1 pair of nozzles

(Picture from official HiFiGo site)


Build Quality

• Build quality is INSANE and EXCEPTIONAL.
• May be one of the most well built IEMs to me, regardless of ANY price point.
• Lightweight, super sturdy, and very stylish finish.

Fit

• Small and comfortable, with a pretty standard nozzle length and width.
• I have no issues with the fit at all.

Tonality

• V shaped
• I only use the default Silver nozzles, as I find the Gold nozzles emphasized on the cons and made it even more sibilant and sharp.

Bass

• Balanced between sub-bass and mid-bass
• Sub-bass has good extension, providing a satisfying rumble.
• Decent slam while being surprisingly tight, controlled, and snappy.
• Lacks body, making the bass feel lean and somewhat lacking in fullness despite its control.

Midrange

• Lower Midrange:
  • Strangely on the hollow side despite the extra mid bass, lacks the bit of warmth that would make it feel fuller.
  • Clarity over weight, which leaves it feeling a bit thin. Perhaps having too much upper midrange affects this as well.
• Upper Midrange:
  • Very forward and energetic, which gives female vocals a very pronounced presence.
  • Can be a bit shrilly due to the lack of note weight.
  • Can also be shouty for people who are sensitive to upper midrange.

Treble

• Treble is sparkly with decent smoothness but there are some quirks.
• The lower treble energy is quite noticeable, making the sound somewhat harsh and sibilant at times.
• Despite this, the treble extension is fairly natural, with a good sense of air and extension without being overly metallic, which is particularly impressive for a single DD IEM.

Technicalities/Others

• Good detail retrieval for the price.
• Separation and staging are above average, with good width but only average depth.
• Imaging is decent but not exactly holographic.
• Timbre is slightly metallic, with a lighter note weight that feels thinner but still quite natural.

Conclusion

• Great overall package for under $50 especially with the exceptional build and inclusions, plus the IEM itself sounds pretty decent for the price despite all my criticisms.
• Definitely not the best sound IEM at its price point, but a good sounding IEM nonetheless.
• Can’t quite compete with more expensive options in my opinion, but still it's a very solid choice for beginners.

Thanks for reading!

Review of the Kefine Klean​

Introduction​

Kefine is another company that I genuinely admire and am a fan of. In my opinion, they sit well among my favorites, like Kiwi Earrs and Simgot. Even though they only have three IEMs in their lineup, including their latest release, I find it remarkable that they have gained so much following and respect in the audiophile community. Personally, I have loved both of their IEMs, Klanar and Delci, for their unique approaches and market positions. As mentioned earlier, they have released another budget-friendly IEM called Klean. I was fortunate enough to get my hands on it for review purposes, but before we proceed, I would like to clarify a few points.

Disclaimer​

*Since this unit tour was organised by the kindly people at Linsoul, I am grateful to them. As I've said in all of my evaluations, the same is true for this one: all of the concepts I've expressed below are entirely my own, original ideas that haven't been influenced by anyone else. If interested, go to this link.
*I am not associated with the connection, and I receive no financial assistance from anyone.
*For the remainder of the review, I will refer to these IEMs as “Klean.”
*I am using different ear-tips for convenience and better versatility.
*Finally, I will only evaluate the Klean based on its performance, even though I will explain how it feels and seems physically and aesthetically.
*My evaluation is based on the standard nozzles that were pre-applied to the IEM. I will discuss the other type of nozzles in a separate section of this review.

Specification​

Klean is a single dynamic driver that houses two 10mm DLC diaphragm drivers. The shells are small and lightweight, which contributes to their excellent seal, comfort, and fit. During my testing, I found Klean to be very comfortable for extended listening sessions. The shells are made of metal alloy with a durable build reinforced by a screw design. The faceplate has a minimalist design that exudes a cool and premium feel. The cable that comes with the IEM is a generic cable that is suitable for an IEM priced under $50. It feels nice in the hand and is well-behaved. The cable has two-pin connectors and ends in a 3.5mm termination plug. There’s also a variation of this cable that includes a microphone. The other accessories included are three pairs of eartips in different sizes, a generic carrying case that came with the last two of Kefine’s releases, and another pair of tuning nozzles that provide different tuning options. In terms of technical specifications, Klean has an impedance of 32Ohms and a sensitivity of 107dB. The frequency response range is from 20Hz to 20kHz.

Sound​

The last two IEMs I’ve heard from Kefine are the Delci and Klanar. Both are excellent and positioned well in the audiophile market as one of the best, which seems true from my perspective. However, when it comes to the Klean, I was surprised. First, they were able to produce such a high-quality IEM in both the physical and sonic aspects. Second, the way they tuned these IEMs definitely puts them in the all-rounder category. The tuning is truly impressive—no unique technology, no DSP, just a driver and a dedicated or custom-made body for the driver. For me, the tuning leans towards a balanced sound signature with a lot of sustained vocals and instruments across the frequency response. The bass is provocative and well-defined, but not overpowering or invasive. The midrange is well-flourished and tonally rich, maintaining the timbre and technical chops of the instruments and vocals. The treble is well-done by many IEM manufacturers, but in the Klean’s case, it’s even smoother and more refined. Let’s delve deeper into the sound to find more about it.

Treble​

Starting with the treble, I believe it has a decent forwardness that brings a soothing experience when properly elaborated. The treble has a richness and a refined sense of vocals and instruments in a vast, spaciousness. This response is not well-known to satisfy your desire for sharp and crisp notes, but rather a natural, timbre-like sound that is almost relaxing to hear. The peak around 13-15kHz brings that sense of air and pushes the shimmer and sparkle in the mix to engage the listener. Personally, I believe that the Delci lacked this quality and brought more of that midrange forwardness compared to Klean. I think that the way Klean presents the upper extension is more attention-seeking and satisfying. Now, the upper treble, as mentioned, has a great extension with the vocals and instruments sounding fuller and richer with a decent amount of details and clarity while pushing out hits of shimmer and bite in the presentation. When it comes to the lower treble, I think it is what gives the upper extension the weight to bring this fullness and richness while also maintaining the bite in the presentation. The forwardness in the lower treble brings the vocals and instruments just right enough to sound lively and engaging. The quality of the notes brings a mesmerizing experience, as the notes don’t shower a lot of energy nor the forwardness in the mix that results in a somewhat mature-like sound. Listening to tracks like Everywhere by Fleetwood Mac, the percussion in the beginning of the song has that soothing, glittering quality that is just right. It doesn’t mask anything but surfaces well enough to sound captivating. The vocals also sound complete and full, extending really well and far, which reminds me of my Prestige LTD. Overall, the presentation of the treble region is extensive, smooth, and natural-like.

Mid Range​

The budget segment of the audiophile market has come a long way, and it seems like they are now closer to mimicking the true characteristics of high-end equipment. In my opinion, the Klean is an excellent example of this. If I compare it to Delci, an IEM from the same company, I believe the Klean offers a truly magical listening experience. The midrange sounds rich and safe, with a balanced and precise note placement. The dynamic quality of the Klean is brought out by the response of the midrange sounds, which are well-resolved with a great sense of space between the vocals and instruments. The Klean provides a fulfilling listening experience, without the typical forward-sounding IEMs that can lead to clarity and sharpness, which can sometimes result in shrills, peaks, or shouts. The Klean offers a well-flourished preset that shows promise in terms of tonality while also subduing any sense of peaky, hot, or shrill characteristics. The upper midrange provides decent forwardness to bring out the vocals and instruments’ dynamics and presence, allowing the space to be filled without congestion due to its open and spacious sound. The vocals and instruments sound fuller and more complete, enabling them to scale to their fullest potential. However, there are certain tracks that made me feel a lack of forwardness. Fortunately, the tunable nozzles allow me to be satisfied with the sound. I will discuss these nozzles in more detail later. The lower midrange is well-presented in the mix, bringing a warm and natural quality to the notes. The notes retain good weight, influencing the higher frequencies and creating a harmonious sound. Listening to tracks like “Somebody That I Used to Know” by Gotye is truly incredible. I am fascinated by how diverse and well-spread out the vocals and instruments are. Both the instruments and vocals sound distinct and well-balanced without blending into each other. Especially when it comes to the drums, which sound incredibly clean and unique while still maintaining the overall structure of the tracks and the individuality of each instrument and vocal. I believe that sounding so different and unique doesn’t necessarily require advanced technical features like other IEMs in the market. As a result, the presentation of the midrange region is rich, fuller, and dynamic.

Bass​

Alright, the bass is done the audiophile way. It delivers a satisfying and engaging experience while producing a good amount of quality and quantity. The bass has a great texture and details, and it creates a nice weight and depth in the mix. I believe Klean brings a response where the bass feels like an integral part of the entire presentation rather than acting independently. This blendfulness and the quality of the notes make it a great-sounding bass. The emphasis is similar to the Delci, which is the sub bass, but I think the response is softer in the sub bass, which helps bring the mid bass out in a cleaner way compared to the Delci. The deep extension provides a pleasant, subtle rumble and impact that meets the heft and necessity of the lows to sound low. When it comes to the mid bass, the drums and bass guitars have a good, thumpy, and meaty presence, but they’re not very prominent in the mix or filling the entire response. The response is well-saturated due to the positioning of the notes and their interactions, as well as the presentation, which is well-regulated. The bass has sufficient control to influence the warmth into the lower mid range while preventing it from becoming muddy, bloated, or booming. Listening to track Rumble by Skrillex sounds fantastic but not particularly enjoyable. The notes have great texture whenever the drop hits and sound complete and full, but the impact is not forward or prominent in the mix. However, when it comes to listening to tracks like Kokoronashi by Majiko, the lows sound clean and refined. The vocals remain unaffected and distinct, and the same can be said about the other instruments. Therefore, the overall presentation of the bass region is well-controlled, detailed, and pleasant.

Technical Performance​

Coming to technical agility, I believe Kefine performed exceptionally well, particularly in terms of stage presence, separation, and imaging. In comparison to its peers, it excelled in these areas. However, I do acknowledge that it could have been even better, which would have increased the cost of its production. Therefore, I must say that I am quite satisfied with its overall performance. Let’s delve deeper into specific aspects.

Soundstage, Sound Imaging & Separation​

The soundstage is incredibly holographic, with a deep and wide soundstage that creates a vast, spacious, and airy area surrounding the listener. This expansive soundstage, coupled with its excellent imaging characteristics, gives the impression of a large soundstage that is both clear and precise. While it may not be the sharpest or most clear sound, it offers a clean and accurate response. One of the standout features of this IEM is its exceptional separation. The distinction between notes is remarkable, allowing me to easily pinpoint the source of each sound with great clarity. This remarkable separation enhances the overall presentation, giving the stage and imaging a sense of impeccable technicality.

Speed & Resolution​

Coming to the resolution, I believe the macro and micro details are adequately presented in the mix. However, I do feel that while the macro details are well-exposed, the micro details are slightly lacking. The attack and decay of the notes are nicely paced to create a natural-sounding timbre, but I believe the resolvability is good.

Sound Impressions ​

Tuning Nozzles​

As mentioned in the disclaimer, I reviewed these IEMs with the standard installed nozzles, which are silver. However, they also come with another pair of nozzles that have a black filter. These nozzles not only alter the sound but also present a completely different experience compared to the silver nozzles. In my opinion, the Klean is the true two-in-one IEM. It can almost satisfy anyone’s needs in terms of bass, midrange, or treble. The Klean with the black nozzles presents a more mid-centric sound. The bass and treble are slightly tamed, while the midrange is elevated, resulting in a forwarded midrange presentation. Vocals and instruments sound clearer and sharper, with a leaner presentation rather than the rich sound produced by the silver nozzles. It’s like going from a balanced-sounding IEM to a more neutral-like tuned IEM. As the upper midrange is elevated and the lower midrange is subdued, the lack of weight and warmth is suddenly felt. However, the more extended vocals and instruments bring a more transparent and clear sound that captures the listener’s attention. The bass on the other hand sounds more controlled and punchier than thumpy and retracts much faster after the impact of the low notes. Surprisingly, like with the silver nozzles, any offensive characteristics are kept at bay and don’t enter the mix. Overall, as the presentation shifted to a more midrange-focused sound, it became more neutral.

Sources​

Sony WM1A - While listening to Klean with WM1A, I immediately noticed a distinct difference in the midrange. The response sounded more forward, bringing the vocals and instruments to the forefront and making them the stars of the show. The treble also sounded clearer and crispier compared to the pairing of Klean with the M15S. Additionally, the bass had a more wholesome and present sound, which added an engaging and enjoyable element to the listening experience.



FiiO M15S - While listening to Klean with M15S, the overall response sounds more forwarded and energized in all aspects. However, the bass sounds more controlled, while the treble is more forwarded. Although this enhances the clarity and detail of the sound, it somewhat narrows the stage’s reach for the listener. Nevertheless, I do notice that the midrange sounds more defined and distinctive.

Tracks​

Millet - Anytime Anywhere
Anri - I can’t stop the loneliness
Kohana Lam - A Few Sentimental
Kohana Lam - Loving Me, Loving You
Uru - Kimino Shiawasewo
Uru - Kamihitoe
Kujira Yumemi - Kenka
Majiko - Kokoronashi
Anly - Sukinishinayo
Kohama Lam - A Few Sentimental
Kohana Lam - Loving Me, Loving You
Miliyah - Kono Yumega Samerumade
Rokudenashi - The Flame Of Love
Yu-Peng Chen - A New Day with Hope
Yu-Peng Chen - Another Hopeful Tomorrow
Yu-Peng Chen - For Riddles, for Wonders
Valentino Khan - Satellite
Kai Wachi - Happier By Now
Jawns - Erotica
ISOxo - how2fly
Kai Wachi - Happier By Now
The
The Weeknd - Popular
YUNGBLUD - When We Die(Can We Still Get High)
Bring Me the Horizon - Kool-Aid
Middle Kids - Bend
FLETCHER - Leads Me On
Loathe - Aggressive Evolution
The Weeknd - Save Your Tears
Sigrid - Burning Bridges
AURORA - Black Water Lilies
AURORA - Runaway
X Ambassadors - Renegades
Lupe Fiasco - Words I Never Said
Macklemore & Ryan Lewis - Can’t Hold Us
Gotye - Somebody That I Used to Know
Jay-Z - Run This Town
Lady Gaga - Poker Face
Lady Gaga - Just Dance
Ladytron - Ghost
Travis - Love Will Come Through
LINKIN PARK - Somewhere I Belong
DJ Shadow - Six Days (Remix)
Hoobastank - The Reason
Ricky Martin - I Don’t Care
Tool - 7empest
Tool - Vicarious
A Flock of Seagulls - Space Age Love Song
Zack Hemsey - Vengeance
Elton John - I’m Still Standing
The Moody Blues - Nights in White Satin
Michael Sembello - Maniac
Guns N’ Roses - Sweet Child O’ Mine
A.R. Rahman - Kun Faya Kun

Conclusion​

In conclusion, I believe Kefine truly set the standards and established the baseline for how an IEM should sound in the budget segment of the IEM market. Kefine demonstrated remarkable skill in maintaining a low price point while delivering a product far exceeding its weight. Personally, I consider this to be the best budgeted IEM available in the market, particularly for its ability to offer two distinct tuning options within the same form factor. Therefore, I wholeheartedly recommend this product to anyone and everyone, especially those who are new or just beginning this passionate hobby.

​

Kefine is a fresh audio brand known for offering class-leading sound at very friendly prices, thereby slowly building its reputation within budget audio circles. Now, the Kefine Klean is its latest product and is considered to be a “budget king” because of great audio performance combined with high-quality construction. The Klean was made for serious and not-so-serious music lovers alike. Its sound is well-balanced and a bit warm, really proving that Kefine holds true to great performance without a corresponding upsurge in price. It also easily adapts and can do anything for just about anything at a very reasonable expense for music and gaming tastes.

Disclaimer​

I received the Kefine Klean IEM from Kefine for review purposes. All opinions expressed in this review are my own, and Kefine has no influence over my evaluation. This review is unbiased and reflects my honest experience with the product. I am not affiliated with Kefine in any way, and I have not received any compensation beyond the product itself.

Note: I am into warm, analog sound that can produce rich and cozy tones, with enhanced bass and midrange frequencies to smoothly render it full-bodied. This captures the organic warmth of music with depth and intimacy, much like the soft texture of vinyl. Natural-sounding, relaxed, and emotionally engaging, this is perfect for immersive soothing listening. Based on my sound preference, I am writing this review.

If You willing to buy this product you can visit Kefine or there HifiGO, Aliexpress store. If you are from Bangladesh you can visit GeekMart and make your pre-order.

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Gears Used​

• Dac Dongle: ddHifi tc44c, tc44pro e2, Fosi audio Ds1,
• Phone: LG V60.
• Desktop Dac & Amp: Xduoo XD05 Basic with (BB OPA2132p, N5532p, JRC5532DD, OPA07CP) op amps, Kaei tap 2, Zen dac V2.
• DAP: Tempotec V3, Ibasso DX180.

Box Content​

• Kefine Klean iems
• Silver plated copper cable
• Tuning nozzle
• Eartips
• Carrying Pouch

Unboxing and Build Quality​

The Kefine Klean is packaged in a stylish, low-key box, its design neat and as minimalistic as the name as the IEM says. Inside, the packaging opens to reveal a set of ear tips, a soft pouch for carrying, a tuning nozzle, and a silver plated OFC cable. It is a no-nonsense presentation that is actually well thought out to set the stage for the aesthetic and build quality of this IEM.

These shells are designed to be ergonomic, sitting comfortably inside the ear, while the moderately heavy construction but the design makes them perfect for extended listening sessions. The surface boasts a smooth finish, and the build quality feels impressively durable for a unit at this price. The cable is thin pliable and strong, showing no microphonics and further adding to the great listening experience.

Nozzle​

One of the best things Kefine Klean comes with two nozzles, silver, and black. Which can not be seen in this price point well I love the silver nozzle over the black one. let’s see how they work terms of sound.

Silver Nozzle: Well this is the nozzle for me. it lowers the 1k – 6k frequency a bit which I prefer the most cause I am a treble sensitive type of person. and because of that, you can feel the bass a bit more punchier and more enjoyable. but you may sacrifice the soundstage a bit, but in my case, it’s worth it to use the silver nozzle. it delivers a more relaxed and musical sound presentation.

Black Nozzle: And with the black nozzle it boosted the frequency 1k – 6k, that’s why you will find more open and energetic mids with a wide sound stage. but it might be harsh for some treble sensitive people. I found (ss, sh) in some female vocals.

Well, so the rest of the review will be based on the Silver Nozzle.

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Sound Signature​

The Kefine Klean follows a well-balanced sound signature tinted with a bit of warmth, which essentially makes it engaging and pleasant to hear for extended intervals. Now, let’s get into minute details regarding the sound quality by exploring it through different frequency ranges.

Bass​

The bass has a full bodied sound ( like waves, so smooth ) with a good control-exerting kick, satisfying and never overshadows mid and treble. The sub-bass extends in moderation, providing a just right depth that doesn’t rise to overwhelming prominence. Mid-bass is present, pleasant, and full without the slightest hint of boominess or muddiness. The thoughtfulness in bass tuning really lets it shine from electronic to rock, adding energy and rhythm while keeping the details intact.

Mids​

But the real standout of Klean’s tuning is the midrange, smoothness (like butter) meets subtle warmth, and vocals receive that luscious, intimate character. Male vocals sound thick and satisfying (makes Mark Knopfler’s vocal so good), female vocals pop out sweet and clear (without been harsh or shouty) . Acoustic guitars and pianos wear a rich, natural timber with quite a commendable level of detail and the intricately laid tracks can have their individual elements distinguished quite nicely. Midrange, in particular, will prove to be especially inviting for genres with vocals and instrumentation styles such as jazz, pop, and classical music.

Treble​

Treble is well extended on the Kefine Klean, tending to slight roll-off right on top, which gives good sparkle and air with no hint of harshness. Such tuning of the treble avoids fatigue. So, the possibility to listen for a longer time without discomfort. Highs are detailed enough to keep the music engaging, but also quite smooth even on tracks featuring brighter elements like cymbals or electronic sounds.
This tuning showed the perfect balance, being clear, and smooth that everyone can enjoy.

Technical Performance​

Soundstage​

The soundstage is moderately wide and quite pleasant to listen to, providing a good feel of space and openness. Maybe not meeting the standard width higher-tier IEMs boast, but at this price bracket, it is definitely spacious. That gives a more engaging feeling when listening to live recordings or orchestral music, where the placement of instruments plays an important role.

Imaging​

Imaging on the Klean is nothing short of impressive, with good, pin-point instrument placement on the soundstage. Instruments and vocals are well-placed with a gratifying sense of separation, even on busier tracks. This impressive capability for imaging makes for a very realistic listen that pleases those listeners to enjoy their favorite music.

Instrument Separation​

That must be one of the striking strengths of the Klean. instruments have never sounded as clearly separated, and even in those messy arrangements, the muddiness was at a minimum. This clarity of separation fills in all the details upon playback, and thus genres having rich, multi-layered composition best suit it, like classical, jazz, and progressive rock.

Gaming Performance​

The Kefine Klean does great in gaming but more for immersive and casual type experiences, in particular. With its moderately extended sound stage and accurate imaging, it can be easy for players to pinpoint exactly where sounds are emanating from-easily a plus in games for complete immersion into their virtual worlds.

For gaming, I use the black nozzle for better soundstage and treble so that I can hear the footsteps clear and crisp.

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The in-game sounds from footsteps and shots fired, down to environmental noises around me-were clear and distinct. The soundstage was wide enough to enable decent spatial awareness, although once more, that is not as spatially huge as some specialist gaming headphones can offer. Again, though, for the most part, the Klean strikes a good balance between detail and immersion in most situations, rounding out the experience without overwhelming the senses.

The bass is punchy, lending weight to explosions and the like without masking any midrange detail, so important for clarity of dialogue. The highs are smooth and detailed enough for those high-frequency effects-like gunfire and voice chat-to come through clear without fatigue. This is, of course, going to be so much more important for listeners that undertake longer sessions where comfort plays an even larger role. All in all, the Klean comes with a good balance between immersive sound and long lasting comfort.

Conclusion​

The Kefine Klean would key everything together, for one desiring a well-balanced sound with a warm and detailed midrange, and non fatiguing treble. Indeed, it is an all-rounder, from build and comfort in fit down to overall sound signature for different genres, including games. Far from class leading by the comparative standards set by higher end IEMs, it’s a commendably good performer within its bracket and quite a pleasure to listen to, particularly for those who love harmonious smooth sound tinted with a shade of warmth.

For more reviews on audio gear, click here

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Introduction

The Kefine Klean is the fourth IEMS of the brand and the cheapest model to date. But that does not mean a drop in quality in any respect. The capsules are made of metal and are manufactured by alloy casting. The inner and outer face of the capsules are secured by means of a screw, which eliminates the need for adhesives that can peel off over time. The dynamic driver has a neodymium magnet and the 10 mm diaphragm is made of DLC (diamond-like carbon), one of the hardest materials in the world. The structure is double-cavity. They come with two sets of interchangeable threaded mouthpieces to provide slight changes in tuning: warm and smooth with the silver mouthpiece and brighter, more transparent and higher resolution sound with the black mouthpiece. The wire is made of silver-plated copper wire. Each strand is composed of eighteen wires of 0.06 mm diameter. The cores consist of three strands. The cable is made up of two cores, so there are a total of 108 wires (18x3x2) in the entire cable. The connection interface is the classic and durable 2-pin 0.78 mm connector. Let's see what Kefine has to offer for only $49.



Specifications

• Driver Type: 10mm dynamic with DLC diaphragm with N52 neodymium magnet.
• Frequency Response: 20Hz-20kHz.
• Sensitivity: 107dB ± 3dB.
• Impedance: 32Ω ± 15%.
• Jack Connector: SE 3.5mm.
• Cartridge Connection Type: 2Pin 0.78mm.
• Cable Length: 1.2m ±0.2m.
• Weight: 10g per side.
• Starting Price: $49.

Packaging

The Kefine Klean comes in a white box with dimensions 108x128x38mm. On the front side there is a real photo of a capsule with the cable. The brand name is in the top left corner and is written in black letters. Below, in the centre, is the model name and a short description. On the back side are the specifications in Chinese and English. Underneath is information about the brand and icons for the certifications it meets. Underneath the cardboard is a black box with a cardboard flap of the same colour with the brand's lettering in the centre, written in silver ink. When the flap is removed, the capsules can be seen in a foam mould lined with black cardboard. Underneath is a box with accessories. The complete contents are as follows:

• The two Kefine Klean capsules.
• A grey zippered case.
• One two-strand cable with silver-plated copper wires.
• Three pairs of black silicone tips sizes SxMxL.
• Two pairs of screw-on tips (black grid and silver grid).
• User's manual.
• Warranty certificate.

Only one set of silicone tips, but the cable is good for the price. Includes two pairs of tuning mouthpieces and a branded zipped case. Kefine has focused on offering a very good quality construction, with a cable that doesn't need to be changed and a grey case that is very practical.



Construction and Design

The black capsules of the Kefine Klean are made of alloy castings. The outer and inner sides are screwed together. They have a very irregular hexagonal shape, with two longer opposing sides and the rest of the faces smaller to round off the shape. On the outer face is a light-grey rectangular pattern. In the centre, the mark can be read in large white letters. The inner face is smooth and soft, without too many curves, beyond the elevation of the nozzles. There is a Torx screw near the edge. Above it is a white lettering indicating the channel. There are two holes, one next to each letter and one near the nozzles. The nozzle tubes are gold-plated and have a diameter of 5.2mm. The filters have a serrated edge and a diameter of approximately 6.5mm. The 0.78mm 2-pin connection is fully integrated into the capsule.
The cable has two cores, three strands and 18 wires per strand for a total of 108 wires. It is silver plated. The sleeve of the 3.5 mm SE connector is metallic and black, and the brand name is written on it in white letters lengthwise. There is a pair of circular grooves near the cable outlet, which is protected by black plastic. The splitter piece is a black metal cylinder with the model name in white letters. It is narrower at the edge. The pin is a black metal ring with a hole inside. It fulfils its fitting function very well. The sleeves of the 2-pin 0.78 mm connectors are black metal cylinders with the channel lettering in white ink. The cable has ear guides.
The construction is very good, the capsules are very solid and have that security screw. It might weigh a bit more, 10 grams per capsule, but the shape is very good.
The design is not bad at all, not too complex from an ergonomic point of view, but the flat shapes adapt well to the morphology of my ears. I like the sober black with few details.
The cable is very good for the price, it is of good thickness and relatively handy.
The nozzles deserve a special mention, as only the crowns are the filters. They are screw-on and have a coarse, obvious toothing that allows them to be replaced very easily and safely with your fingers.



Adjustment and Ergonomics

The domes are of medium size and their flat-sided shape with rounded corners integrates very well into the pinna. They fit flat, while the mouthpieces are somewhat short and insertion can be only shallow, though somewhat deeper if more suitable tips are used.
Although each dome weighs 10g, the good fit does not compromise on ergonomics. The capsules do not move in the pinna and the fit is unique, durable and occlusive, providing a high level of isolation.
The hardness, fit and comfort make them suitable for everyday use, for outdoor use and for light sports such as brisk walking.



Sound

Profile

Kefine Klean IEMs are inexpensive IEMs with two tuning mouthpieces. According to the brand, the silver-plated mouthpiece offers a warm and smooth sound, while the black mouthpiece provides a higher resolution, brighter and more transparent sound. In my opinion, there are many models with a similar tuning to the Klean with the silver-plated mouthpiece. I would choose the silver-plated mouthpiece for long listens. It is a tiny U or W profile, with very rounded curves and no peaks. The profile achieved with the black mouthpieces is doubly excited in the upper mids and first treble, adding more energy in the 2.5 kHz and also in the 5 kHz. The latter peak can be somewhat more aggressive in an area where the human ear is quite sensitive. Therefore, any excess in this area can be detrimental. As the silver mouthpiece profile is the safest, I have preferred to use the black mouthpiece for this review, as it is more critical and daring.



Bass

There is no doubt that dynamic drivers with a DLC diaphragm can reproduce bass with great power. Thanks to the high hardness of the material, the bass is precise, natural and deep. This is how the bass of the Kefine Klean can be described. Starting with the very low-frequency pure tone test, the 20 Hz sound really natural, with a strong sensory component and hardly any oscillating character, which makes them very pure and very realistic. The fact that the first note starts off so well only presages a great bass range. As the frequencies climb, you continue to perceive very little colour and more energy, and maintain that great physical substrate, while increasing the volume and space occupied. The result is a deep, dark bass, physical and sensory, with power, but without being predominant in the mix. Of course, the DLC diaphragm allows the bases to be very compact and dry, as well as generating very concise, tight and fast decaying hits. The execution of the bass drums is fast, with no aftertaste, not too elastic, just enough, and here we can appreciate that the mid bass is very restrained: it exists in the right proportion to provide volume and strength, but avoiding bleeding into the mids. Undoubtedly, the presence of the bass is more prominent with silver mouthpieces, but it is more compensated with black mouthpieces.
In my classic test of dirty, complex and unfiltered bass, the Klean's hold up very well, as if reproducing the worst bass was a piece of cake. The speed and precision of the driver allow the bass lines to be very clean, quite deep and well marked. The worst situations are under control and I could only criticise some symptoms of reduction to a simpler reproduction. But perhaps this is the result of how well the Klean's work in these situations. There's no stress, the driver doesn't suffer and that shows in a natural, maybe not too rich, but very successful performance, layering the layers very well and separating the complex lines of the bass drums in a clear and concise way. It's hard to believe that a $50 bass sounds so effective and realistic.



Mids

As usual in this type of tuning, with a rather technical bass, the first half of the mids is perceived as quite clean. With silver mouthpieces, this part is warmer and denser. With the black mouthpieces, a little more of the base is lost in favour of the middle and upper frequencies. The male voices lack some body and physicality. Overall, they feel quite close in the mix, but without that density that makes them fuller and deeper. As a result, this first half feels leaner, a little thin, though with good presence and cleanliness. It is not a very busy phase and feels freer and more transparent. The energy level of the second half helps a lot. Although it is true that it can slightly favour sibilance, it is not a completely splashy profile, but with a point of vivacity and sought-after expressiveness, but not overdone or too excited. Thus, already in the male voices, one can appreciate how the higher parts are favoured and the accent is placed on the ending of the notes.
The timbre, although natural, is subtly deviated towards brightness, but without losing the neutrality that distances it from the new, darker META curve.
The female vocals are in their element. Although I still notice a certain lack of strength in their base, the rest of the way through until they are fully executed sounds very good. It's not a display of nuance and resolution, but there is a clear desire to sound quite full, without falling into an analytical profile or losing smoothness or control. I think Kefine wanted to bring the two sides of the Klean midrange sound through the two mouthpieces it comes with: on the one hand, that softer, smoother and rounder sound, warmer and more suitable for long hours of listening. On the other, a slightly sharper, richer and more exposed sound, with the risk that this entails, but without pushing it to the limit, just adding a little more sparkle, light and spice to the upper mids and first treble. This is how the Klean's upper zone develops, with that brighter aspect, but with a mixture of subtle warmth and sparkle, which is not polarised, but well blended. In this way, the upper mids don't feel splashy or forced, but maintain a good balance with the black mouthpieces, ideal for those looking for an extra point of clarity and accentuation of detail.



Treble

The Klean's treble starts with a good initial sparkle, with a slightly elevated, but very well controlled energy level. The result is a punchy base followed by a control zone that stretches into the air zone in a very remarkable way. All this gives the high notes a very natural and full sound, but without stridency. Once again, Kefine has sought to reach the border between musicality and excitement. And I think they have succeeded. Its treble is not only maintained in power and control, but even stretches noticeably into the air zone, maintaining a level of representation that makes the high notes have a good, quite realistic timbre, while the harmonics do not become artificial. Again, it is a commendable effort for a $50 IEMS to achieve a level of finesse and delicacy within a balanced and fairly even smoothness. And all this with a simple dynamic driver. There is a certain punch and a slight crunch that gives authority to the treble, but always within a coherence and order. And I think that's not easy to achieve. I could conclude that the treble is sparkling, relatively thin and delicate, but always within a controlled and well extended range.



Soundstage, Separation

The Klean's scene is relatively large on all three axes, filling a space larger than a quarter sphere. There is a sense of roundness in the volume generated, with very good laterality, remarkable depth and that point of height that elevates the notes and gives them a certain enveloping sparkle. However, it is not extraordinary in this respect. But it is quite clean and transparent. But, above all, it is orderly and coherent, and maintains musicality as its main premise. With the black mouthpieces it is cleaner and more transparent, and it gains the impression of incipient micro detail, quite well achieved for an ensemble that does not seek to be analytical. I feel subtle nuances subtly expressed with considerable ease and clarity. Reaching this point is already a great achievement, especially considering the price and without looking for technicality above all else. The Kleans have enough sharpness and resolution to show that good level of detail, while maintaining a coherence and balance in their more fun and sedate presentation. So, once again, you have to appreciate the resolution of a $50 driver and the tuning that powers it.
The image is coherent, well presented, with a logical and realistic positioning of the elements, without artifice or showiness. It is rather a solvent and successful image.
The separation is noticeable and there is a slight darkness in the background. You can dig into it and discern that small detail, not too sharp or delimited, but there it is. And much better than in more expensive sets. Not bad at all.



Comparisons

KZ ZS10 Pro 2 1111

The KZ ZS10 Pro 2 cost $56 and have 5 drivers (1DD + 4BA). They are made of a hybrid construction with resin on the inner side and a metal panel. They have four tuning switches instead of interchangeable mouthpieces. The packaging is minimal and includes a single cable. The Klean Kefine Klean surpasses them in construction, design, presentation and accessories, and is less expensive.
The capsules of the KZ are thicker and, although their ergonomics are not bad, the comfort and fit of the Klean is clearly superior.
In terms of profile, the KZs can be tuned to different degrees of bass. But with all switches in the ON position, the frequency response more closely resembles an excited, rising W. The Kleans with the black mouthpieces have a W-shaped profile, but softer in the treble. It is worth noting that the curve is very similar up to 1000 Hz.
The Klean's are a little easier to move and, for the same power, sound louder.
I already commented in the review of the KZs that their bass was good, dark and deep, but with a medium speed. The Klean's bass has a superior punch, punchiness, texture, speed and technical quality. It is not so dark as to become dull, but it is better behaved. In the very low frequency pure tone test, the Klean's are subtly more physical and less coloured, as their wave character is lower, giving them a more realistic and natural response.
In the middle range, the first half is warmer and denser in the Klean. The male voices have more body, presence and a more accurate timbre. In the KZ, everything is leaner, with a point of imbalance and a more pronounced V-feel. The Kleans have a more homogeneous character, are more pleasant and musical.
There is also a more pronounced thickness in the female voices, which sound fuller and more realistic. The KZs, on the other hand, have a somewhat more synthetic sonority, comparatively speaking.
In the treble, the Kleans have an explosive start, but their energy level decreases afterwards. The opposite is true of the KZs: they are controlled and smooth at first, but then fill out in the mid-range. This gives them a somewhat strange and less natural timbre, which also adds to the behaviour of their BA drivers, which are further away from the realistic and organic sound of the Klean.
The KZs may boast more drivers, but the Kleans gain in micro-detail, clarity, resolution, balance and musicality. The sound is crisper, while the KZs are more muted and nuanced, with details omitted in comparison. The soundstage is superior, the sound is more open and transparent, and separation is more clearly perceived. The Kleans, with one driver, do better than the KZs with five.



Conclusion

The young Kefine brand is also demonstrating its know-how in the $50 segment. Without any revolution, playing it safe, but offering a very musical and expert tuning, something that is already a hallmark of the brand itself. The Kefine Klean is a reliable bet for those who want a tremendously musical IEMS with a bit more of everything, including good technical skill. With excellent die-cast metal construction, screw-secured capsules, a quality cable that avoids having to buy a new one, and two pairs of mouthpieces to change the tuning: warm and smooth with the silver mouthpiece; brighter, more transparent and higher resolution sound with the black mouthpiece. The Klean can easily become a fully recommendable set as an all-rounder, for everyday use as well as for leisurely and enjoyable listening.



Sources Used During the Analysis

• iFi GO bar Kensei.
• EPZ TP35.
• Tempotec V3.
• Burson Audio Playmate 2.
• Aune X8 XVIII Magic DAC + EarMen ST-Amp.

Purchase Link



You can read the full review in Spanish here

This hobby is an escapist's dream. Escape from daily routine and distress that's causing you via something as sincere and everlasting as listening to music. I believe that the power of music is still not fully understood since it works in mysterious ways. Allow it to do its magic on you and let your worries dissolve in melody.

Having had the possibility to try so many different sets in a relatively short time I felt obliged to go ahead and express my gratitude by trying to help some lost souls out there, just as I was when I first stumbled upon this weird hobby about wired earphones – so yesteryear! … I thought. Possibilities are seemingly endless and only by getting to meet the right people did I manage to jump onboard the train heading the 'right' direction without getting off-track thousands of times along the way. Make sure to understand the helping person's preferences and you too can find your footing and hit the ground running in no time.


Quick Intermezzo About Me

I won't bore you for too long with personal trivia, however my quick & short background resume goes as follows. Currently I am 27 years old and more in awe of sheer power of music by the day. I have always been moved by music just that slight bit more than average, I'd say. My spending started with a roughly 200€ Bose bluetooth speaker back in my first grade of highschool. What an extraterrestrial thing that was in early 2010s. And it keeps on playing to this day – a true testament of quality. Also sounded fantastic back then, nowadays … yeah, not so much. Lots of BT speakers, TWS, car audio speakers, IEMs, etc., later bring me to this day when I truly consider myself an audiophile. What brings me the most joy beside listening to music is singing, so I am currently participating in a choir and challenging myself with solo vocal covers (check the links in my signature to hear my projects). Unsure where all this leads, but the journey itself is marvelous and life is nothing but a journey.

My preference lies somewhere in the neutral camp with just an ever so slight tilt towards warmth, but I try to keep an open mind and truly appreciate any outliers that dare do it differently and succeed. Our ears vary, so do our brain and tastes. I am an advocate for respectful discourse, especially in topics that don't even have many objective undeniable truths. Audio is one of those.

My most listened genres are, in no particular order: jazz, singer/songwriter, slow-paced electronica, ambient, rock, metal, blues, trance, techno & pop.


Disclaimer: I have received the Kefine Klean directly from Kefine. Even if I wanted to shill this to the moon and back, I am way too mindful of others' money to overly hype stuff that does not deserve it, so there's that.

Feel free to check out their official site here: https://www.kefineelec.com/en/ProductDetails.aspx?iProId=25


How My Reviews Are Structured

This will be a barebones stripped down version of my reviews which I will use on sets below a certain price tag from now on. Meant for those sets where writing thousands upon thousands of words is not really worthwhile. Let's face it, no one's reading a book about a 49USD set, so let's trim the weeds and cut straight to the point with a quick rundown of packaging, accessories, design and fit, then moving on to my graphic tools and finishing with a few comparisons.

I have left the set to burn-in for 50+ hours and listened to songs of varied genres to better convey what one can expect from the Klean. As sources I have been using my FiiO BTR7, Venture Electronics Megatron, iBasso DX180, and Venture Electronics RA2B-FE AMP + Prime DAC (in short, called the 'VE Stack'). Certainly no lack of power and quite a different taste on all. Listening was (mostly) done at a volume ranging between 75-85dB. I am using the stock tips and cable.

Here is the quick and rough description of how I understand various star ratings:

Do not even think about it
It has too many drawbacks and gets demolished by competition
This item has the potential but feels a bit too bland and has multiple issues
Wonderful item with rare and mostly subjective drawbacks
Eargasmic performance with all the aspects covered at an incredibly high level

Keep in mind these ratings are certainly affected by the item's price in the overall assessment too. Sometimes that will result in slightly higher score than based solely on my scoring of bass, mids, and treble, while other times it results in a slight penalty if I deem the item a tad overpriced.

In layman's terms - anything rated below 4 stars overall does not get a space in my regular rotation and is either stored and revisited some time later again just to see if my thoughts have changed, or it gets gifted.


I am still catching my stride on how to describe the sound aspects in a clearer way. It is a slow but enjoyable learning curve. I am attempting to make my reviews as ballast-free as possible. The graphics were the step in the right direction, I feel. Capturing the essence of sound characteristics in a less wordy way is next on the list. We all have our own busy schedules and I understand reading a review for 15+ minutes is in (nearly) no-one's interest.


Let's Get Going!

Packaging, Accessories, Design & Comfort

I always take into account the item's price and want to see most of the budget used on the IEM itself, so while packaging is indeed very important for that initial impression that colours our perception, it's secondary to many other things. With that preface, I am happy to say that Klean strikes a great balance. It offers a decent cable and a case, while the tips selection is a bit lacking.






Klean is a tiny set that is bound to fit nearly everyone. The nozzle isn't extra short, so I think that shouldn't be a problem for most either. It feels heavy and durable and its appearance goes along with the form factor. It is a fit and forget kind of set.




Graphics, Graphs & Scores

As mentioned a little earlier, I have worked on trying to cut down on wordiness and all excess gibberish and rather improve upon my nikbr trademarked graphics to truly be able to compare IEMs visually since that offers an easier-to-comprehend, more interactive and simply more appealing experience.

These truly cover most topics in a pretty straight-forward manner. I have described each of these in a bit more detail in my previous reviews. If anything remains unclear, here I am at your service.

Six Basic Traits

comfort is second to none. It comes at a cost of not isolating too well. Bass struggles a bit due to its occasional boominess, midrange is well done with ample openness and naturalness. Treble is well judged and sweetly detailed for being a single DD. Overall cohesion is nearly perfect, but again, the boominess just slightly detaches the bass.
Magic Balance Boards


Soundstage Measurement Tool

Good width with okay height and depth.

Quarter Circle Playground

It stays very much dead center. It's neither laidback nor energetic per se, and I would say the bass and treble cancel each other out to help reach a neutral W-shape to my ears.

Overall scoring

Looking Very good. Bass struggles a bit with slight midbass softness and boominess. Mids and treble are almost spot on.


Extra

Fun factor: Another tough one to simply close by saying either yes or no. It exemplifies a well balanced set that is not dull by any means. Is it the most energetic listen ever? No. Is it fun while randomly playing through a varied library? Very much so!

Q: What kind of source to pair it with?
A: A neutral source will do just fine. The tonal balance is spot on from the start.

Q: What genres are its strength/weakness?
A: No real standout failures while it does not completely excel at any certain one either.


Comparisons



These two sets were the ones I ended up choosing. To the left of the Klean is the Sivga Que, another single DD, while to the right is the FitearxQDC SuperiorEX - yes, single DD as well. Yes, they are both more expensive than the Klean, but the Que is like a better accessorized and arguably better looking Klean, and the SuperiorEX tries to do a bit of the same as the other two in being a rich sounding single DD. Let's give these a fair shake over a couple of songs.

I used the iBasso DX180 and the same cable and just reattach different IEMs to give this A/B the fairest battling grounds. The cable is my best to date, the Effect Audio EROS S II.




Soldier of fortune, Deep purple

Guitars are one of my go-to's. Not easy to pull them off in smooth, weighty, but bitey and lively fashion. It often leans either way. Working my way through the three sets, the Que leans far towards the weighty and smooth side, individual notes are not the focus, but rather to make the whole package feel like a musical journey which brings the somewhat blurry and thick texture. Klean is less in your face in the upper mids and makes the guitar even less forward, but it's not as free and unruly in the low mids, hence the guitars sound a bit more sterile. Individual notes are more pronounced and offer clearer microdetails. Still not my perfect guitar replay. SuperiorEX is much easier to drive so I need to lower the volume by 30%. Guitars are free of bloat and aren't too spicy, but they feel somewhat hollow. None of these excel at guitars is the final answer. If I had to line them up, it'd go: S-EX > Klean > Que

Male vocal is an often occurrence in my playlists. So, back to Que. It offers a well placed vocal and the song is built around it. It's chesty, touching, and sufficiently detailed. Klean places it further back but not in a bad way, it simply sounds like the vocalist was actually standing further away. That provides an even larger perceived stage which goes well this song. It's not as detailed as on the Que, though. S-EX makes it sound more ethereal as if it's floating around and thus makes it more difficult to pin point singer's placement. It also sounds more veiled than the other two. Result: Que > Klean > S-EX


Summer by Emeli Sande

Female vocal obviously comes in multiple flavours, but Emeli's velvety and alluring quality is a real gem. Que does it very calmly and she feels even warmer and weightier. I miss some of that luxurious detail. The song therefore becomes a bit more tedious and not as touching. On the Klean she is much clearer and out in front. Her placement and clarity allows for better detail perception and allows the song to breathe better. On the SuperiorEX I like her placement and feel it's most well balanced to the rest of the mix, but she has this veiled and somewhat muted feel. It is more rounded and larger in how much stage she occupies. I like my female vocals forward while still well judged, so: Klean > S-EX > Que

This song also offers a great test for low bass tactility, texture, precision, and midbass attack. Let's see how it goes starting with the Que. Que offers a big bass that is more diffused in nature, not a very clean and surgical one. It has plenty of character and happily follows the song's progression down to the lowest note in its chorus. Initial note attack could be better and overall bass quantity could be more for this song. Klean is just a bit snappier at the start of the note, but still lacks midbass solidity. Low notes are not a problem, it descends into low 30s sweetly, but has a bit less texture and naturalness to it than the Que. Superior's note beginnings are better defined and less strained. It also rumbles the most ecstatically and gives me a feel it could easily keep on descending into infrasonics. The bass quantity is the highest, also in part thanks to its very attenuated higher range. This gives us a score of: S-EX > Que > Klean


Rosita by Coleman Hawkins and Ben Webster

I'll be looking out for timbre, detail retrieval and soundstage+imaging. Without further ado, Que excels in providing a natural harmonic listen full of character. It remains timbrally correct throughout and expands nicely to the sides as well as having okay depth and height. A truly well-suited set for this groovy masterpiece. The Klean is almost as characterful as the Que while having a more pronounced subbass and treble. This makes it a bit less organic to my ears which goes well with its appearance vs the wooden-faceplated Que. It's timbrally fine, but I preferred the way Que rendered the sax. It's also a bit less spacious. On to SuperiorEX, the note weight is a standout feature I spot from the get go. All notes are larger and more dense. Only the sax is too hollow and occasionally plasticky, however, which kills the whole gig. The stage feels more crowded, they step on each other's toes. Imaging-wise, it's close between the Que and Klean, but Klean takes it. Overall: Klean >= Que > S-EX

Summing Up The Kefine Klean

This is a quality set that I feel does so much right and it easily falls into the 'Suggested' category. Either as a gift to your closest ones or to yourself, this set will not disappoint anyone but the biggest opposers of neutral-warm leaning sets. Even then, in this avalanche of warm sets, this has the correct balance to tastefully counterbalance the healthy bass shelf. At this price, it is a no-brainer.

Thanks for reading and stay wonderful.

DISCLAIMER

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

The Kefine Klean can be gotten here: https://hifigo.com/products/kefine-klean or https://www.amazon.com/dp/B0DK4WR4FJ/kefine+klean/ (no affiliate links).

SPECIFICATIONS

• Driver configuration: 10 mm DLC diaphragm dynamic driver
• Frequency response: 20 Hz - 20 kHz
• Impedance: 32 Ω
• Sensitivity: 107 dB
• Cable: 2-pin 0.78 mm; silver-plated copper cable; 3.5 mm termination
• Tested at: $49 USD

ACCESSORIES

Other than the IEM, these are included:
- 3 pairs of wide-bore silicone eartips (S/M/L)
- Cable
- 2 pairs of tuning nozzles
- Carrying case

The accessory line-up is okay for the sub $50 USD asking price, nothing ground-breaking, but focusing on practicality.




There is only one set of silicone eartips included, with no provision for alternative types or foamies. Nevertheless, this sole set of tips are serviceable from a sound and comfort perspective.




Included is a stock silver-plated copper cable. This is on the thinner side, but is braided well with minimal tangling. There's a chin cinch for added grip, with negligible microphonics.




We have a small carry case, which is semi-rigid externally, with inner webbing. It isn't that big, but should be able to fit the IEM and cable at least.




Lastly, we have 2 pairs of tuning nozzles, which we will dive into below in more detail.

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


BUILD/COMFORT



The housings are manufactured from metal-injected mold, and are built like a tank, culminating in a smooth matte finish. The inner aspects are comfortable to be worn for longer listening sessions.



Being a vented IEM, isolation is below average. I did not encounter any driver flex on my set.


DRIVABILITY

I tested the Klean 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 easy to drive, with no hard requirements for amplification.


INTERNALS/TUNING NOZZLES

The Klean utilizes a 10 mm DLC diaphragm dynamic driver.

This IEM is quite versatile, boasting of 2 sonic options via tuning nozzles:


With the black nozzles installed, we have a bright U-shaped curve, which is very resolving. The bass is tight and fast, with crisp transients. The treble is clear with solid technicalities, though it may be spicy and sibilant for the treble-sensitive.

On the other hand, the silver nozzle confers a warmer and bassier signature, with thicker note weight and less sizzle in the top-end. This setting is definitely more relaxed and smoother, though we lose technical chops compared to the aforementioned black nozzles.


SOUND & TECHNICALITIES

The following impressions are done with the black nozzle in use.

As per the graphs in the previous section, this setup furnishes a bright U-shaped tone.

This has a sub-bass focus, with decent descent but no big basshead reverberant rumble. The bass is however, very tight and clean - as its "klean" namesake would suggest - and bass texturing is well done for its $40ish pricing. So it is a case of quality over quantity.

The lower midrange has a slight dip, and then we hit a 9ish dB pinna gain, which translates to forward vocals that are just at the edge of shout (it may be more prominent at louder volumes as per the Fletcher Munson curve).

The black nozzle provides decent treble extension with good resolution and clarity. Micro-details are captured well, though cymbals and high-hats may be a tinge spicy, with some sibilance in play. This black nozzle setup would be a kindred spirit for trebleheads, though treble-sensitive peeps better keep to the tamer silver nozzles to reduce fatigue.

In the area of timbre, the Klean performs okay, it is bit thinner in note weight on this black nozzle setup, with the silver ones giving a thicker and fuller sound.

In technicalities, the Klean has above average soundstage. Micro-detailing - as alluded to - is pumped through well in the mix, and for a sub-$50 set, imaging and instrument separation are well above average.


COMPARISONS



The Klean will be compared against other single DDs below $50 USD. Hybrids, multi-BAs, and planars, which have their own pros and cons, are left out of the comparisons.

Once again the following impressions are done with the black nozzle in use.


Tin HIFI C2 2025

The Klean kills the lacklustre C2 2025 easily in every technical department, from imaging to micro-detailing to soundstage.

The C2 2025 is however, smoother in the treble and thicker in note weight.


EPZ Q1 Pro

The Q1 Pro is more Harmanish, with a mid-bass scoop out and a more sedate top-end.

The Q1 Pro is weaker technically, with a smaller soundstage with less pronounced micro-details and imaging.


CONCLUSIONS



For sub-$50 USD, the Kefine Klean is a solid choice, espousing good price-to-performance ratio.

This IEM is quite a versatile beast, with 2 tunings on offer - a laid-back and relaxed thicc sound versus a more technical and brightish affair with a "klean" and textured bass. However, there are some trade-offs among the 2 signatures, with the silver relaxed nozzle sounding a bit lowFI, and the black analytical nozzle having some treble fatigue and sibilance. Timbre is otherwise quite natural, more so on the silver nozzle.

In the non-sonic arena, build is solid, with easy drivability and comfortable ergonomics.

All-things-considered, this IEM should be in the conversation for a budget introductory pair, and is kind of a jack-of-all-trades.

Hello friends!

Today the review is about a new product, hot, intriguing and for some, controversial.
Kefine company has released another dynamic IEM. Two versions of Delci have not had time to rattle off, another interesting thing appeared.
The name of the model is Klean. With a “K”. The name is based on the English word Clean, and the first letter is replaced in favor of the company's name. A little symbolism.


Today will be a comparison with current models, we will analyze the sound on different sources.
The cost is about 55$ for today, without taking into account sales and discounts.
Let's go to the main part!

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Packaging

The packaging and bundling has been redesigned. The box is completely different. It is smaller in size and of higher quality.
The front part shows us the appearance of the headphones with the full name.
On the back part there are classic configuration information in several languages and manufacturer's contacts.

Sliding the shirt we get access to the main box with a hinged lid, reminiscent of Simgot's packaging solution. Inside there are 2 boxes inside - for the IEM and accessories.



There is a dense fabric case, which reminds me of a similar case from ARTTI. Inside silver-plated cable, two cores, metal quality fittings and functional separator. The plug is 3,5 mm with 2Pin 0,78 mm connectors. And of course a set of 3 pairs of good quality silicone eartips.

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Сonfiguration

The IEM have one dynamic driver 10 mm with DLC diaphragm. From the features of the magnetic system N52 and high-performance voice coil, named DAIKOKU CCAW.
There are also interchangeable filters that have a real impact on the sound.
Sensitivity is 107dB, impedance 32 ohms.
Frequency range 20 Hz-20 kHz.
I used Xinhs 7N copper cable and JVC Spiral DOT Pro fx 12 eartips.

---

Appearance

The shells have also been completely redesigned compared to past models.
The eartips fitting issue is completely gone now. The IEM fit 99% of the time comfortably with any eartips. Passive noise isolation is excellent.

KEFINE appears to be pushing its way towards the entry-level audio market segment as they keep releasing some well-tuned sets with an affordable price tag on them. Since the release of their well-received models, the Klanar and the Delci, KEFINE continues to be bestowed with some approvals and plaudits from the audio community on the quality of their products.



And the audio item that will be featured is their latest entry-level IEM model, The KEFINE Klean. And this is apparently their third model that still makes use of similar driver configuration but they added some features that were implemented before on from their Delci AE.



The KEFINE Klean still furnishes a single dynamic driver with a DLC diaphragm which is known for its tensile strength and resistance against external force for better surface tension on its dual cavity magnetic structure. In that process, it provides a better transient response for deeper and stronger bass response, clearer midrange and then, clarity and high resolution treble response.



The driver was then encased in a solid CNC-milled aluminium alloy shell in a compact size shell chassis. Its outline shape has a rounded trapezoid shape and both parts of the shell underwent an anodising process to achieve that matte-like finish on its surface. It has a nozzle made of brass and it can be detached and the attached other nozzles with different tuning filters that are also included in the box. Like all KEFINE models, it uses a bi-pin connector of 0.78mm as its interlocking mechanism for its detachable cable.


9
The compactness of its shell's size allows it to be worn by almost all ear type sizes as it offers a comfortable fit and also gives a good passive noise isolation from external noises from the outside surroundings. The quality of its stock cable is quite decent as it is flexible, offers some entangled-resistant and doesn't have any microphonic issues at all and it is made of silver-plated copper wire in a braided 2-core structure with a 3.5mm termination jack on its end.





The product packaging of the KEFINE Klean is quite minimalistic on its approach but it offers a decent amount of inclusions inside of its packaging box just like all previous sets that they released before.



Here are the following contents we can find inside:

• Pair of KEFINE Klean IEM transducers.
• Stock cable
• A canvas fabric storage case.
• A pair of tuning filter nozzle (black-coloured filter).
• Three (3) pairs of balanced bore silicone ear tips of different standard sizes.
• Paperwork like instruction manual and Q.C. card

The KEFINE Klean is relatively a sensitive one that can be driven with decent sources such as smartphones, tablets and laptops. A normal gain power output will deliver an optimal performance which sounds full and sufficiently dynamic quality.



As for tonality, since this set has a detachable tuning filter nozzle feature, it offers two distinctive tonal profiles as I will indicate the following tonal description on each tuning filter nozzle.



Silver Tuning Nozzles - a mild U-shaped sound signature which also has balanced-warmish tonality, it has a more emphasis on the low and high frequencies with slight dip on the midrange.
Black Tuning Nozzles - it has a brighter U-shaped sound profile as it has more emphasis on the high frequency part while the midrange appears to have more dip across the frequency range.


(FR graph was provided by @baskingshark , credits to him)


LOWS/BASS:

SILVER FILTER

The bass quality on this setting is quite well-balanced as it has a noticeable sub bass presence and adequately textured mid bass that gives a rumbly, punchy and impactful bass response. While it has solid bass depth and texture, I don't still consider it as an ideal for bass head's preference on low frequency.

On its sub-bass depth, there's a discernable amount of reverberations and grumble from sub bass-focused instruments. The quantity mid bass texture on it conveys a firmness on its musical notation on instruments and vocals concentrated on the bass notes and it also slightly permeates across the midrange.

INSTRUMENTS:

Bass guitars - weighty and sombre sounding.
Double basses - heavy, dark and menacing sound
Kick bass drums - dark and sonorous sound.

VOCALS:

Basses - they have those deep resonating vocals to give a dark and thick sound.
Bass-baritones - full, hefty and resonating voices which have a slight dusky sound that defines this vocal type.


BLACK FILTER

Evidently, the tuning of this one appears to be more focused on sub bass presence rather than mid bass texture unlike the SILVER FILTER. It has a more rumbly, incisive and a tad cleaner bass response but it somehow penalises the mid bass texture to sound less full and less authoritative.

The sub bass presence is even more apparent as I clearly felt the rumbling and reverberations from certain instruments like synthesisers, drum machines, low tuned bass guitars and double basses. The mid bass texture appears to sound a bit leaner on its note weight that also affects the tonal colour of some bass-clef instruments and low octave male vocal types.


INSTRUMENTS:

Bass guitars - resonant with a tad hollow sounding.
Double basses - a bit mellow and rasping sound.
Kick bass drums - rumbling yet softer sounding.

VOCALS:

Basses - they still have those rumbling and resonating sounds but noticeable it has less heavier and less darker tone.
Bass-baritones - they have a resonating voice but it sounds less full and deep to give that gruffness.


MIDRANGE:

SILVER FILTER

The midrange presentation of this one is a bit slightly recessed but it provided that adequate warmth to give a full, well-bodied and a nearly natural tonal colour on vocals, especially male ones and instruments.

As I mentioned, this type of tuning will most likely benefit on most types of male vocals but some female vocals like contraltos and mezzo-sopranos will also gain on this one too. The brasses, percussives and some strings will have these organic and almost life-like sounds from this tuning filter mode.

VOCALS:

Baritones - vocals have a warm, smooth and steely sound.
Tenors - vocals sound brassy and rich which is good for spinto tenor down to heldentenors.
Countertenors - smooth, velvety and pleasant sounding.
Contraltos - rich, heavy and strong sound from their chesty vocals.
Mezzo-sopranos - smooth and velvety sounding.
Sopranos - its more of a creamy side of sound with some emotiveness which is excellent for dramatic sopranos and to some extent, spinto sopranos types.

INSTRUMENTS:

Guitars - they sound a tad warmer and a bit meaty sounding.
Cellos - mellow, sonorous and calm sounding.
Violins - full, sensuous and but rounded.
Trumpets - they sound substantial, full and round.
Trombones - powerful and round sounding with a dark tone.
Horns - they have this warm, full and resounding sound.
Piccolos - graceful, delicate but it has a less brilliant sound.
Concert flutes - they have a rich and soft sound on them.
Clarinets - warm, rich and mellow sounding.
Saxophones - they sound warm and sombre.
Snare drums - they sound hard and shuffling.
Tom-toms - they have that warm and resonant sound.
Field drums - full and sonorous sound.
Kettledrums - resonant with a hint of velvety sound.
Pianos - warm and mellow tone as it has a rich and round sound.


BLACK FILTER

It seems that it has a more noticeable dip and presents a bit more leaner midrange presentation compared to the SILVER FILTER mode. But with some changes on its tonal characteristics, they sound more transparent, crisper and quite spirited while retaining that smoothness that the other tuning filters have.

With this kind of tuning it will add some sense of spaciousness and energy on some female vocals like mezzo-sopranos and sopranos, and also on some instruments like strings and woodwinds.

VOCALS:

Baritones - they sound more lighter and also a bit more mellow but still smooth but it has a bit less warmth and richness which sounds better on light and lyric baritones.
Tenors - a bit bright, clear and a tad brassy sound which suits well with leggero and lyric types.
Countertenors - tender and a bit fiery sounding on their vocals.
Contraltos - it sounds less depth, less warmth and less darker tone as it sounds less plush and less husky from their chesty vocals.
Mezzo-sopranos - it has a golden, fiery and emotive sound.
Sopranos - they have this clear, lofty, and gleaming sound in which lyric sopranos will fare better.

INSTRUMENTS:

Guitars - balanced to a tad dry sound from their notation strings.
Cellos - lively and sensuous sounding.
Violins - stately, clear and lustrous sound.
Trumpets - full and a bit vivid sounding.
Trombones - hard and eruptive with a hint of metallic sound.
Horns - sounds velvety and resounding.
Picollos - they sound clear and brilliant.
Concert flutes - bright and silvery sounding.
Clarinets - they have a lively and brilliant sound.
Saxophones - lively and bright tone with a hint of reedy and hollow sound.
Snare drums - precise and bright sound.
Tom-toms - less warm but still resonant sounding.
Field drums - menacing and resonating sound.
Kettledrums - resonant, hollow and a bit dry sounding.
Pianos - they sound even and bright as it has clear and some brilliance on its overall sound.


HIGHS/TREBLE:

SILVER FILTER

The treble quality of this one is relatively smooth, well-balanced and even with a modest amount of air and enough sparkle on its brilliance section on this particular frequency region. The upper-mids up to the presence part is just mildly elevated just enough to give some clarity, detail and definition on vocals and attack of instruments.

I already mentioned its modest airy extension of its brilliance section and sufficient degree of its sparkle quality.

INSTRUMENTS:

Cymbals - lustrous and undulating sound.
Hi-hats - a short dull yet full tone on its distinctive chick-y sound.
Celestas - mellow and velvety sounding.
Glockenspiels - it has a lustrous sound.


BLACK FILTER

This tuning setting has a tad brighter response as it has more gleam, crisper and a tad airier treble response. The upper-mids up to presence treble section has more emphasis as it highlights the clarity and definition on vocals and instrument for better delineation on them.

On its brilliance section, it has a sufficient amount of its airy extension with an ample intensity on its sparkle.

INSTRUMENTS:

Cymbals - bright and sizzling sound.
Hi-hats - short buzzing and resonant sound.
Celestas - it has a sweet and shimmering sound.
Glockenspiels - it has brilliant and silvery sound on its key notes.


SOUNDSTAGE, IMAGING AND OTHER TECHNICALITIES:

Its perceived sound field dimensions are in between average to above-average size with a median width on its lateral span and decent height reach and good depth that it gives me a moderately roomy head stage within my aural sphere.

On its stereo imaging, this is probably its strongest point on how it pinpoints the almost exact cues of well-separated instruments and vocals in a concave-like decently layered soundscape. This is quite an impressive performance for a single dynamic set that is capable of playback some of the most complex multi-instrumental tracks that I usually tested for this testing phase without any sort of congestion.

Driver coherency of this one is quite competent; it has a notable transient response that some phasing issues and distortion are near impossible on this one. Resolution capability-wise, it has satisfactory resolving for both macro-dynamics and micro-detail retrieval as former shows solid and ample depth its note composition while latter is able to show some details and nuances like vocals ends, notation attacks and reverb tails (BLACK FILTER appears to have a more sharper definition compared to SILVER FILTER).


PEER COMPARISONS:

KEFINE DELCI AE

• Klean's predecessor and a bit more pricey, it still retains the DELCI regular's design profile.
• It has a metal-alloy shell chassis but its driver uses a composite material on its diaphragm.
• KEFINE's first model that features detachable tuning filter nozzles.
• Due to its detachable tuning nozzles, it offers U-shaped sound profiles, from warm to bright tonality.
• In SILVER TUNING, compared to Klean's it has a similar punchiness on the bass response but it has less authority and impactful but appears a bit more cleaner, a noticeable recessed midrange presentation and similar smoothness on the treble response albeit it has a bit more airy extension.
• On technical performance, both have similar performance but the DELCI AE is quite more resolving on resolution, while the Klean has better stereo imaging presentation.

SIMGOT EA500LM

• The successor of the mega-hit EA500, but it's a bit more pricey compared to the Klean.
• Like the Klean, it has a metal shell chassis but on its dynamic driver, it uses a composite material on its diaphragm.
• It has a similar quantity of inclusions like one type of silicone ear tips.
• As this IEM has a detachable nozzle system, it offers different types of sound signature with three tonal profiles in which this set makes it more versatile.
• On its RED RING BRASS nozzle setting, if it is compared with SILVER FILTER mode of the Klean, it has more rumble but less punchy bass response, a similarly warm and rich midrange but a tad more energetic on it, and a bit brighter treble response with more sparkle.
• On its technical performance, it has an average to above-average sound/speaker stage size in concave-like stereo presentation while it is quite a tad more resolving in terms of resolution capabilities.

TWISTURA D-MAJOR

• It is on the same price point with the Klean as both of them are at around US$50.
• It also has a metal alloy shell with an unusual design language but it has composite diaphragm on its 10mm dynamic driver.
• This one is pretty well-accessorised as it includes another type of ear tips and a USB-C DSP headphone amp which is an unusual inclusion.
• Like the Klean, it also has detachable nozzles with tuning filters that offer other tonal profiles, but it offers not just two but three sound profiles.
• On its BLUE RING NOZZLE settings, compared to BLACK FILTER Mode of Klean, it has tighter, less impactful bass response, a more recessed, less warmth midrange that affects the timbre of some vocals especially baritones, tenors and contraltos, and a more brighter treble which is more susceptible to sibilance and piercing sound.
• Technical performance-wise, it has a similar performance with the Klean but it has a sharper micro-detail retrieval but appears less natural sounding on timbre.

As I concluded this product assessment, KEFINE will always stick to their goal that they will deliver a refined audio product to music lovers at the best value at an affordable pricing, and Klean is indeed the core of it. The Klean is now the most affordable KEFINE product right now and its tonal performance alone will assure an engaging and pleasant listening experience among audio enthusiasts. As I mentioned, its imaging capability is one of its highlights. I am quite impressed by a single DD set like this IEM on how I was able to determine some of the spatial cues of instruments and vocals.

KEFINE Klean is now available in selected online vendors on e-commerce stores, non-affiliated link guaranteed.

LINK: https://www.linsoul.com/products/kefine-klean?srsltid=AfmBOoqjL56OE_jh8wJxTbULt3avkQSfxxPlhZ9sOsSNqND76cwcP9up

For more KEFINE product reviews, check out my previous product reviews links below.

● KEFINE KLANAR

● KEFINE DELCI

● KEFINE DELCI AE





SPECIFICATION:

MODEL: KEFINE DELCI
IMPEDANCE: 32Ω
SENSITIVITY: 107dB
FREQUENCY RESPONSE: 20Hz – 20KHz
CABLE LENGTH: 1.2m
PIN TYPE: 0.78 2-PIN CONNECTOR
PLUG TYPE: 3.5mm
DRIVER UNIT(S): (1) DYNAMIC DRIVER


TRACKS TESTED: ( * = 16-bit FLAC, ** = 24-bit FLAC, *'* = MQA, '*' = DSD, *'= .WAV)

Alison Krauss -When You Say Nothing At All *
Jade Wiedlin - Blue Kiss**
Led Zeppelin - When The Levee Breaks **
Mountain - Mississippi Queen *
Queen - Killer Queen **
Guns N' Roses - Patience *'*
Eric Clapton - Tears in Heaven '*'
Sergio Mendes- Never Gonna Let You Go '*'
Pearl Jam - Daughter **
Roselia - Hidamari Rhodonite *
Assassin - Fight (To Stop The Tyranny)*
Celtic Frost- Visual Aggression *
New Order - Blue Monday *
The Corrs- What Can I do (unplugged version) *
Jimi Hendrix Experience - Voodoo Child *
The Madness- Buggy Trousers *
Metallica - Motorbreath **
Mariah Carey- Always Be My Baby *
Destiny's Child - Say My Name *
Malice Mizer- Au Revoir *
Mozart - Lacrimosa *
New York Philharmonic Orchestra - Dvorak- Symphony 9 " From the New World." *
Eva Cassidy - Fields of Gold (Sting cover)*
Michael Jackson - Give In To Me *
Exciter - Violence and Force *
Diana Krall - Stop This World **
Debbie Gibson - Foolish Beat *'*
The Sisters of Mercy – Lucretia My Reflection**
Suzanne Vega – Luka **
Lauren Christy – Steep *
Ottoman Mehter - Hucum Marsi *
Diana Damrau - Mozart: Die Zauberflöte*
Type O Negative - Black No.1 *
Felix Ayo - Vivaldi: Presto **
Three Tenors - Nessum Dorma *
Mercyful Fate - Witches' Dance *


P.S.

I am not affiliated to KEFINE nor receive monetary incentives and financial gains as they provide me a review unit for an exchange of factual and sincere feedback from yours truly.

Once again, I would like to send my gratitude to Mr. Collin Yang for providing this review unit. I truly appreciate his generosity and trust towards me and other reviewers.

Kefine Klean Review​

​

Kefine Klean Review​

Intro​

Hello, this review and feature covers the latest from the audio brand Kefine named the Kefine Klean. The Klean is a single dynamic driver earphone with an MSRP of right around $49, which happens to be the least expensive set made by this young brand. I was actually surprised to see this price point after such enormous successes as the Kefine Delci (Delci Review), and the Kefine Delci AE (Delci AE Review). I would’ve thought Kefine would shoot a bit higher in price. Perhaps break the $100 threshold. However, here we are, and I am very curious about where the Klean lines up sonically against the other two single DD sets from Kefine. It is surely going to be interesting.

Kefine​

Every review that I’ve conducted featuring a Kefine set (only two… Lol) I’ve spoken of how impressed I am with this young but very successful brand. I will always root for the little guy, or the smaller outfit. Kefine was actually born from a group of friends who decided that they could do better than what was currently on the market. However, not only could they craft and create better products, but they could do so cheaper as well. The name “Kefine” actually stems from the founder’s name “Ke” and the word “refine” which is almost a mission statement in and of itself. Kefine promises that in the journey to making the best products for the smallest price they have to make use of every cent. Nothing wasted, no arbitrary and pointless accessories, nothing unnecessary, and a simple packaging helps to keep costs down and in turn keeps prices down for you and me. I won’t go too long with this, but I do want to lightly champion this smaller brand. Of course, Kefine certainly doesn’t need my help…I think they’re doing just fine on their own.

It’s your money…​

At the moment of writing this intro, I’ve just received the Klean, and I am about to spend a long amount of time listening. However, there are certainly some things I’m looking for. First off, the Klean finds itself in a very competitive price point with some absolute ballers under $50. Perhaps the best price to performance sets in this price point than any price point in audio. I feel I can say that, maybe. So I really want to see how it does considering there are sets like the Simgot EW200 (EW200 Review), Rose Technics QuietSea (QuietSea Review), CCA Rhapsody (Rhapsody Review), KZ PRX (PRX Review), KZ ZS12 Pro X (ZS12 Pro X Review), BGVP P05 (P05 Review), Celest Pandamon 2.0 (Pandamon 2.0 Review), EPZ Q1 Pro (Q1 Pro Review), Celest Ignite Beast, Inawaken Dawn, Kiwi Ears Cadenza (Cadenza Review), Celest Wyvern Abyss (Abyss Review), TRI Draco, Juzear Clear, KZ AS10 Pro (AS10 Pro Review), and about 50 more iems which truly compete. By the way, those were only the sets at the tip of my tongue. No doubt it is a good time to be a hobbyist in the best hobby that our earth has to offer…my opinion of course. Another thing I’m looking for is if it makes sense to simply save up and look at a higher price point. To add to that, does the Klean compete with sets at higher price points? Our ultimate goal is to help you, the buyer, to make a decision that makes sense for you and your money.

See you in a week…​

So, there’s some stuff to unpack here, thankfully it is an absolute joy to do so. At this point in the process the Klean is being burned-in, and I am awaiting critical listening for the next week or so. With that said, I’ll see you all in about a week (in the sections ahead). The Kefine Klean everyone…

Non-Affiliated Purchasing Links:​

–HiFiGo
–Amazon US
–Amazon JP
–Aliexpress (HiFiGo)
–Aliexpress (Kefine)

Disclaimer:​

I received the Kefine Klean from Kefine as a review sample and in exchange I will conduct a full review and feature at Mobileaudiophile.com. I have not received any payment or any other form of compensation for this review. This set is a review sample iem. Kefine has not requested to pre-read any review and doesn’t have any control over “what” or “when” anything gets published to mobileaudiophile.com. All thoughts within this review are my own, though please take note that I will always have my own biases. This is impossible to get around. I try to be as objective as my subjective self can be, but this is an opinion piece folks. Thank you to Kefine and thanks for reading.

Gear used for testing​

–Ifi Go Blu

–EPZ TP50

–EPZ TP35

–Aful SnowyNight

–Shanling H0

–Fiio Q15

–iBasso DX240 with Amp8 MK2

–Shanling M6 Ultra

Packaging / Accessories​

Unboxing​

As per usual, the Kefine Klean came in a reasonable simple small white box (average size) that has a graphic of the Klean in the front and some specs in the back. Perfectly nice packaging, but simple. As Kefine says they would do in their mission statement. That is, keep the packaging simple, nothing unnecessary, or over the top, keep prices low. Still the unboxing isn’t bad at all. Take off the box top and you’ll see the Klean sitting in foam cut-outs. Under that layer you’ll see the gray carrying case. Inside of the case are a couple baggies. One has the eartips in it and the other has the tuning nozzles. You’ll also see the cable in the case as well. That’s about it. Not bad by any stretch for a $49 iem.

Eartips ​

In the packaging Kefine includes three pairs (S, M, L) of silicone eartips. Those being dark gray in color and very similar to KBear 07 tips. Just like the 07’s these tips have a semi-wide bore and are also very rigid and fantastic for sealing. The flange is firm, stem is firm as well and the bore size works very well for the Klean. In fact, this is one of the few times that I didn’t feel the need to tip-roll. This almost never happens. These are really nice eartips and actually fit the Klean nicely in the sonics department. Not much more to say other than… Awesome!

Carrying Case​

Kefine also included at $49 a carrying case which is most certainly not the norm at this price. I don’t use cases all too often, but I was pleasantly surprised to see one included. Also, it’s actually a very nice case. A fantastic size for carrying in the front pocket of my jeans too. About 4” in length, 3” wide, and 1 ¼” deep. Close to a perfect size and shape for my pockets actually. Oddly enough this is how I deduce how nice a case is. Lol. Just slim enough to not look ridiculous in my front pocket. Anyways, the case has a nice fabric covering and comes with a working zipper! How about that? It actually works! Additionally, the case is just large enough to store the Klean and the cable along with the EPZ TP35. Perfect! You know how I said I never really use cases? Well, I used this one every day. I realize that this isn’t the biggest deal, but not many sets come with cases at this price and so it is nice to see. That’s all.

Cable​

Also included in the packaging is a very good cable for this set and this price point. I don’t really expect anything worth using but I actually used this cable for all 3.5 single ended listening. That said, it is in fact a 3.5 single ended 2-pin cable. It’s a white colored SPC (Silver-Plated-Copper) cable with a total of 2-cores, 108-wires in total, white in color with black fittings and is actually nice to look at. It fits the Klean aesthetically in my opinion. Also, functionally it is nice too with no microphonics (very little), it doesn’t spring apart every time I roll it up (this is huge), and it isn’t super heavy and unyielding when in the ear. Now, many of my sources run balanced and so I did have to use balanced cables and did so to get the most of this set. The cable I chose was the Tripowin Noire modular cable and used the 4.4 balanced jack for most of my critical listening time. The Noire fits the color scheme fairly well, but I also like the sound pairing. I truly don’t feel this is necessary (cable swapping) however as the included cable is very good for the price point.

Build / Design / Internals / Fit​

Build Quality​

The Kefine Klean is like any other Kefine set in that it is built very well. The Klean is an all-alloy earphone crafted by way of injection molding in a very sophisticated manner. I love the six-sided design which is a rather unique shape. I found the nozzles to be medium in length, not so long that they run too deep, not so short either. At least for me. The nozzles themselves measure right around 6.5mm at their widest using my calipers. That’s with the tuning nozzles attached. You’ll notice two small vents as well. One for the front acoustic cavity and one in the rear acoustic cavity. Really the Klean are just a nicely built set for such a price tag. Granted, we’ve seen these types of builds around this price point by many other sets and they are all good for the price. That still doesn’t take away from how well the Klean are built. Kefine does it right and they know how to make an appealing looking iem.

​

Design​

Now, the design will go one of two ways; you either really like the design, or you won’t. I feel the great majority will really like the six-sided build with the grid-pattern faceplates and the unimposing “Kefine” written down the middle. The black color is bold, classy, and masculine and the golden nozzles contrast very well against it. It’s quite gallant and distinguished. I cannot tell you how much I like simple and yet tasteful design language. It’s not easy to do. There’s such a fine line between classy and dignified looking and boring or too underwhelming. I realize that we don’t buy earphones for the design first and foremost. However, the design matters to a degree, to at least some people. I’d say Kefine nailed this one. That’s just me though.

Internals​

Kefine decided to once again go with a single dynamic driver setup inside of the Klean. That being a 10mm dynamic driver with a DLC (Diamond-Like Carbon) diaphragm making use of N52 Neodymium magnets set up in a dual cavity structure. Kefine also used .0035 mm Daikoku voice coils as well. Nothing we haven’t seen before as far as driver material etc. Still, it’s all in how it’s implemented in the end. Every slight variance changes what we ultimately hear and based upon what I hear, Kefine produced a fine sounding set.

Tuning Nozzles​

Like I’ve said, the Kefine Klean comes with two sets of tuning nozzles to further dial in the sound to fit your preferences. Those nozzles are the black and silver nozzles, and each presents the frequency in a slightly different way. I’ll make this pretty quick because there really isn’t a whole lot to say. Anyways, the nozzles are the type which thread onto the earphones with male threads on the earphone side and female on the tip side. Be careful if these little guys as it will be very easy to lose them. I suggest changing them out over something large like a bed or a table because if these fall, they can quickly become lost. Just a suggestion. So, the “Black Nozzle” is definitely more rambunctious, with a lift in the upper midrange and lower treble providing a more energetic sound of the two. The black nozzle bass also feels a hair less meaty, maybe less commanding. Great for better detail retrieval, more crispness, better instrument separation etc. The “Silver Nozzle” on the other hand is bassier, slightly more relaxed, less energetic but also less sharp or glaring. The silver nozzle has a smoother demeanor and in my opinion is the more musical of the two. Coincidentally, it is also the nozzle that I used for the entire review process. I definitely enjoy the silver nozzle more.

Fit/Comfort​

As far as fit, the Kefine Klean is very comfortable for me. There isn’t much I can say that will resonate with you concerning fitment, but the Klean fit me like a glove. How they will fit you is another question. The second I put them in it was a very good feeling, an easy seal, perfectly cradled in my ears. This makes comfort something special too. Again, for me.

​

Drivability / Pairings​

Output power​

The Kefine Klean are rated with an impedance of around 32 ohms (give or take), as well as a sensitivity of roughly 107 dbs which translates to “the Klean are easy to drive”. In my opinion the Klean absolutely need nothing more than a smartphone to get a fulfilling listening session in. I used my iPad, and the sound was actually quite good. Having said that, it does pay off to a degree to give the Klean some juice. Like most any iem. Beyond juice, the Klean also adapts to different source tonalities very well too, but I’ll cover that next. As far as output needed to bring the Klean to its best fidelity, I’d say around 50-100 mw @32 ohms. It doesn’t take much folks. Heck, even my 53mw Fiio UTWS5 worked like a charm. I use 4.4 balanced on most source devices and found that no matter the device the 4.4 seemed to sound a hair tighter in note structure. Of course, this is just me listening as best I can from one cable to another. So take it with a grain of salt. Still, I do feel that giving more power does help the Klean as it does scale well with power.

Source pairing​

Now we get to a somewhat polarizing subject in source pairing. Now, I’d say the Klean are warm/neutral in tonality with a slight leaning towards warm. What this means is that the Klean doesn’t have an outright specific preference for source tonality pairing. At least I don’t feel they do. I quite literally went through about 17 sources in total, and many sounded very nice. Pairings such as the brand new EPZ TP35 or the TP50 both came across awesome for me. The neutral of those devices yet slightly more energetic tonality does help. Another that I adored listening to was the Shanling H0. Really a great tonal pairing. As far as daps, my Shanling M6 Ultra which is warm, velvet, and clean dynamic, was easily my favorite device out of any of them. Something about that warm resolving sound with a boatload of output power makes the Klean really sing. Of course, I used many devices during critical listening and each one came across good in their own way. I honestly don’t feel there is some requirement to find a certain tonal color from your source device. Go cold, bright, neutral, warm. As long as you enjoy it, that’s all that matters.

Sound Impressions​

Note: I should note that I burned-in the Klean for roughly about three days prior to listening. I also gave the Klean about a half day after burn-in to actually listen to them. Of course, I didn’t really listen beforehand to know if this helped or not. I know this doesn’t help you, but it is in the name of full disclosure. All my music is flac or better files stored on my devices. Also, I listened almost exclusively to UAPP (USB Audio Player Pro), along with Hiby Music Player at times as well.

So far Kefine has a strong track record, albeit a slightly more limited record. But still a good one. Every set they’ve made is a solid product. The Klanar, Delci, and Delci AE are all very good sets for the money. The Delci and Delci AE are two sets that are warmer, with that groovy and robust energy, good note weight, bassy, smooth. Each are different variations of those descriptors. I’d say the same about the Klean, only I do feel the treble is a hair more noticeable and the spectrum as a whole is a very small titch tighter. This is great in my opinion, because the Klean is the cheapest of all of their iems. Leave it up to Kefine to create iems which thrive in price to performance.

So how does it sound?​

The Klean is warm/neutral in tonal color with a slight V-shaped Harman inspired sound signature. I say that because the sub-bass is emphasized with slightly recessed lower mids, boosted upper mids and there’s a nicely balanced emphasis in the treble as well. I’d say a variant of a Harman tuning. I don’t feel that any one area of the mix necessarily dominates the rest of the frequency either. As far as timbre is concerned; the Klean sounds like what I would call organic, or “mostly” organic, less vibrant, less unnaturally illuminated, less artificial and dare I say… a nice version of “natural”. Now, energy could be a bit more rambunctious for some folks as the Klean is not the most expressive set as far as bombastic macro-dynamics are concerned. The Klean won’t make the hairs on your head dance. Instead, the Klean ushers in a smoother rhythmic type of sound which borders on a lean-lush approach (to note weight) and it does present some shimmer, some air, and moderate levels of brilliance up top as well. So, it’s not so spirited, bouncy, or sprightly as some sets in the price point. The Klean also isn’t outright thick, weighted, overtly warm, or dark either. Very close to the Delci AE in the way it presents music. That being… a well-adjusted spectrum with a pleasing dynamic balance as well as a musical flare that’s effortlessly groovy. My version of “musical” today… that is.

Laid back?​

Some may call the Kefine house tuning “laid-back” and I would partially agree. I suppose it depends on what you subjectively feel “laid-back” even means. I could say this… you definitely don’t get those Simgot bright-energy vibes. You won’t hear anything too glaring in the upper mids and lower treble, sibilance is held in check, and the Klean won’t provide that ultra crunchy crispness that a set like the Simgot EW200 or EA500 would give you. However, the Klean also isn’t without that dynamic energy. A smidgen of warmth keeps the edginess or coarse note outlines at bay as the emphasis given to the pinna rise is well balanced against the slightly more lifted low-end. The Kefine house tuning is actually really well played as their sets run along a fine line. Very much Harman inspired yet without the pitfalls which seem to plague Harman sets. Also, the Klean isn’t as warm as something like the Letshuoer S08 for example. There’s more luster in the treble, more air, less bass fullness, and a better balance in my opinion. The Klean finds itself in a great spot tonally, not pushing any area of the mix too far, yet not completely disregarding any area of the mix either.

Condensed Sound Between the 20’s ​

Really quickly let me run through the sound in each 3rd of the mix in a condensed version for those who really just need a quick rundown. So, the bass region is just-above-moderate in terms of bass depth, impact, fullness and density. It’s a beefy bass that doesn’t fill out the sound field too much, doesn’t mask too badly and is still tight enough to sound defined and clean. It’s a fun bass that doesn’t seek to overwhelm the mix. Next, the midrange is only a hint recessed around the lower mids yet with a nice boost of shimmer in the upper mids. The midrange is smooth overall, semi-thick note weight, reasonable technical abilities and very musical with a touch of crispness when a track calls for it. Next, the treble region is mostly non-fatiguing in the way that it isn’t ear gouging and bright. Not full of crispness and crunch either yet not devoid of crispness. However, the treble carries some nice emphasis to offset the bass with nice detail retrieval for the tuning and plenty of air. I hear no sibilance (at least not enough to be bothersome), no shrillness or splash either. Treble timbre is actually quite nice if you like a balanced rendition of the treble.

Condensed Technicalities​

Technical ability is good for the tuning as well. I hear solid details for a smoother sound, decent enough instrument separation, and the soundstage is what I’d consider about average (average is good btw) with pretty nice depth too. Also, Imaging is probably above average and is in my mind a strong suit of the Klean. Really a solid sounding set that should be considered among the best that the under $50 market has to offer. Providing the sound signature agrees with you…of course.

Bass Region​

One of the first things I check upon receiving any iem is the bass. Bass is usually the underlying bedrock of most budget sets today and that is mostly true for the Klean. Finding out the emphasis will dictate so many other regions too. So, always my first check. I went straight to Lil Baby & Lil Durk’s collaboration effort album The Voice of the Heroes and the 1st track I play is “How it Feels”. Right away you get a sense for the meat of this bass region, the depth, and the solidity of each note. The bass doesn’t sound too forward in the mix or too potent and focused to mask over the rest of the mix too badly. I’d say the Klean is in line with the better sets in the price point in this regard. Nicely impactful with a thudding presentation and a very enthralling style bass. It hits pretty hard without losing the refinement within each note. Per the track of course. I can tell the Klean doesn’t come across soft, pillowy, or weak in this area. Quite the contrary actually. I’d call the Klean’s bass fun, yet in a mature way. It’s tight for the quantity, not loose or flabby, and the bass has a clean note outline. You can tell right away that the low-end serves as a light foundation of this set. Having said that, the Klean does have an overarching balance of the spectrum. Bass notes have some nice refinement for $49 and the bass is in the fun side, but you should keep expectations in check. However, for $49 I’m very happy.

Some bleed…​

The bass region does bleed over into the midrange a bit and the bass does give the midrange (particularly the low-mids) some additional note body and warmth. I feel this is a good quality of the Klean but I’m sure there will be those who only desire an untouched and pristine midrange without any bleed from the bass region. Also, I wouldn’t call the low-end a “fast bass” type either. Of course, this is neither a good quality or a bad quality, more so it is a preference one way or the other. In my opinion the low-end is more atmospheric, less snappy, harmonics seem to run their course without seeming to be “cut-off”, which can be very satisfying during a listening session, but maybe not as great for faster or more complicated bass tracks. In the same breath, I would not call this a slow bass either. When you combine good density, clean notes, and pretty nice note definition it usually makes for a non-muddy sound. Beyond that, the low-end doesn’t come across one-noted and it isn’t a basshead set. The sound down low is beefy enough, but it won’t please those who yearn for a bulbous and bullish bass-boi type sound.

Sub-bass​

The sub-bass reaches deep enough to indulge most genres and satisfy the listener. Sub-bass rumbles in tracks which require it with a good haptic feel to the sound. I wouldn’t say it’s the most guttural in the price point, but it is one of the price points’ higher quality sub-bass efforts. The Klean has that hard lined attack, a fast thud approach, and is very engaging for the cost to own it. I’d also say that the sub-bass is the focus of the low-end and comes with a round presentation on most notes (depending on the track) as well as a low droning style. Nothing flat or too wide in presence. It is more condensed and concentrated than it isn’t with most sub-bass notes. There’s some definition there which doesn’t muddy the waters of the mid-bass as much as some other sets. I’d say better than the Delci in this regard, which is pretty nice praise. Like I said earlier, it comes across clean but does so with plenty of fullness. I realize that not everyone wants a lifted sub-bass such as this, but I find it very good for what the Klean was tuned to. For example, the track “Lone Star Lake” by Waxahatchee delivers a concise, composed, and commanding bass guitar groove to begin this track. For instance, the Delci was slightly less compact, slightly more softened in comparison as well. Again, I know that some folks desire an even more expeditive, textured and snappy sub-bass but I would think the majority of people would be happy with the sound here.

Mid-bass​

The mid-bass is less convex and lifted then the sublevels of the bass region but that doesn’t mean it’s any less impactful. Let’s put it this way; the Klean has a fun style bass and will replay a bass heavy track with bass heavy presence. I don’t feel anybody is ever going to call this set weak in this department. Certainly, lifted to the point of full, rotund, and gravelly bass guitars. Bass guitars like in the song “Use Me Up” by Lake Street Dive. It’s simply full without blurring or masking and on this track, you can easily make out the finger slides and the abrasive edginess as well. It has a natural feel to it. Kick drums are also pretty solid on this $49 iem. The track “Billie Jean” by Weezer is a track I routinely use for testing as the kick drums hit right away and are very repetitive which really helps as a reviewer. The Klean once again has a concise and authoritative boom. Not as thunderous as more elevated iems but the Klean can really come across in a full-bodied and thick way while also keeping a reasonably tight note delivery. Again, nothing weak or sloppy on the Klean. Now, will it be to your preference? I hope I’ve explained it in a way that makes sense. Basically, for the quantity, the Klean presents a quality sound down low, it’s a fun sound, attack is immediate, and decay lingers just enough to call it atmospheric. For $49 it’s pretty gratifying.

Downsides to the Bass Region​

The obvious downside is the level of low-end emphasis. We all know plenty of folks who desire less of a showing from the bass. Perhaps snappier, even more fast and rigid with better texture. Having said that, there isn’t many sets which actually carry that type of bass replay at these prices. You don’t have good balanced armature bass at $50. Maybe some planar sets like the KZ PRX can provide the texture, but even it has a bigger emphasis. Beyond that, plant of folks also won’t want to see any bleed over into the midrange. I completely understand this thinking too. Sometimes I too want to hear a pristine and uncolored midrange without the haze that some bleed can induce. That all said, the low-end is decently detailed, nicely defined for the price and emphasis, and is authoritative in a balanced way against the rest of the mix. The bleed into the mids doesn’t sound as though it is detrimental to my ears either. So as with anything it will come down to what you prefer. However, I truly feel that for $49 the Klean does very well per its tuning.

Midrange​

The first word which comes to mind is probably “smooth”, quickly followed by “enriched” and “musical” when considering the midrange. That said, there is a slight recession within the midrange, particularly in the lower-mids, but I really don’t feel that this recession takes anything away from the Klean’s sound. Mainly because the midrange has very good presence and a certain engaging quality which seems to follow more musical iems. With the silver tuning nozzles threaded on I find the Klean to carry almost a milky type of rhythm and very nice note weight, lean-lush, not too thick, never thin and very cohesive with solid energy as you enter into the upper midrange. The Klean can replay with some shimmer when needed even though I’d describe this set to have more of a creamy approach. I would still say that resolution is nice for such a rich and musical sound. It’s a clean sound which is a nice contrast to the heavier low-end. Brings on some macro-dynamic energy to the mix. I’d even say that detail retrieval is fairly nice as well in this region too.

Timbre​

However, the best quality of the Klean’s midrange (to me) has to be the overall timbre & tonality. Just a silky rendition of an organic approach. It has just enough energy to not come across as dull and enough of a sprightliness to replay with fairly tight transients in my opinion too. Again, you aren’t missing many details here. Beyond details, separation of instruments isn’t bad either. Not by any stretch of the imagination. To add to that, Imaging is certainly one of the best attributes of the Klean as instruments and vocalists share the stage with very good left to right and front to back placement with coherent and decisive note outlines for a smoother type of sound. Nothing grainy, nothing metallic, nothing sharp, glaring, processed or artificial sounding to my ears. Really a well-tuned midrange if an organic sound jives with you, if a clean midrange which outlines a very melodic semi-rich body.

Lower-midrange​

As I said, the lower midrange is a hint recessed to my ears. Please don’t look at this like a negative though because the Klean’s low-mids have a very nice natural weight and warmth which comes across as lifelike. This additional weight comes from the bass region successfully spilling over into the midrange in a measured and helpful way. I’ve said already that I know there are those who much more enjoy a pristine and pure lower midrange, but for those who prefer something a bit more realistic, I’d say the Klean will fit the bill. Male vocalists have just enough authority to their voices, and they don’t usually carry any edginess to them. Always a smoother note progression and cadence. Singers like Chris Stapleton in the track “Higher” sounds completely unprocessed with the right tonal warmth to not exaggerate the coarser inflections to his voice. Especially when he’s belting out with emotion like in the track “Sometimes I Cry”. He never really sounds knife edged at the crest of those notes. While I don’t think the Klean necessarily specializes in male vocals, I also don’t feel that males sound bad at all. “I’m Still Fine” by The Red Clay Strays is proof of that with the Klean in my ears. Again, very good presence for the tuning and for the price with a timbre accurate sound and plenty of weight for a more emotionally gratifying type of listen.

Upper-Midrange​

The upper midrange has a slightly thinned down, bubblier and livelier of a sound. With a 10db pinna rise it isn’t so intense that it causes fatigue though. I enjoy the level with which Kefine decided to counter the bass region with here. Like I said, there is a nice dynamic balance on the Klean and the upper mids are (in my opinion) a benefactor of that tuning. Female vocalists in particular. However, everything naturally sounds more effervescent and sweeter in this region. Females benefit from the slightly lusher note weight, yet the definition of those notes is pretty clean. Transients are speedier to decay and there is some level of crispness in this region as well. Instruments sound very nice with this tuning. Violins sound silvery, with enough edge. Piano has that resplendent type of resounding tunefulness & strings have enough bite to satisfy with good body. Percussion has just enough snap and kick to sound dynamic for stuff like cymbals, snares, etc.

Those females…​

Yet it’s the females which make this tuning work well for me. Vocalists like Adele. Pick any track. Her voice comes across with that hearty and sweet rasp which coalesces very well on the Klean. Songs like “Hello” have that haunting emotional quality which works on this set whereas it may not come across as well on some other sets under $50. Caitlyn Smith sings “High” and her voice goes from subtly soft and feathery leading up to the chorus and then so very mellifluous and ballad-like in the chorus. I like that the chaos of instruments and sound during this chorus doesn’t seem as though it’s too blurred, too smeared or too chaotic. Like I said transients are fairly quick, notes are clean, separated well and they can work around more complicated sections of music nicely for a single DD. I feel Kefine did a very good job on this set and females certainly pay off. Obviously, there are mid-centric and vocal-centric sets which may come across traditionally better, but the Klean puts it all together very well.

Downsides to the Midrange​

There aren’t a whole lot of “downsides” that I could list here that won’t be positives to the next guy. Really a well done sound here. However, not everyone enjoys a set that isn’t bloated in bright energy and crystal-clear note transparency. There are analytical sets which can resolve subtle details better with more distinct note separation. Not everyone wants a musical sound. So many hobbyists love a detail oriented and airy sound. I suppose that is one place that the Klean is just average in. That is… airiness. I wouldn’t call the Klean the most open sounding, yet I also wouldn’t say the sound feels closed in and narrow either. Those who enjoy a warmer, even richer, even darker sounding midrange with even creamier closer to velvet style mids may want to pass to. So, the Klean will not please everyone, I think we know that. Still, I really feel that Kefine tuned this set with a very nice balance and a pleasing tonality and timbre.

Treble Region​

The treble region of the Klean is just-past-safe for me. Meaning, I don’t consider it a knock-off safe tuning which keeps all dynamics and vivaciousness tucked away so as not to offend. I don’t hear that. Actually, I’d say there is some solid vibrance and some spunk with this treble. Just a peppering of it. A little spritz of extra brilliance and treble luster. However, you could also call it non-fatiguing and you wouldn’t be wrong. You could also say the treble region is “somewhat” laid-back. Now, what I believe we have here is a smart treble tuning from Kefine in which they made damn sure to create the best balance they could while still remaining musically gifted, organic across the mix, but also not totally dull. We’ve heard those dull and boring sets. Those darker treble sets, no life, all note weight and veil. Without question the Klean is NOT that. I’d actually say the treble has some good energy and even some air, some openness. Also, I’d say that the treble does bring some levity to the entire frequency. One thing about good timbre is that it takes a whole frequency to get that good timbre. Thus… the treble is not bad at all.

Well balanced​

With this non-offensive treble, the people at Kefine also tuned in some crispness up top. That’s right, this isn’t some smooth fest with no bite. On the contrary, there is some treble bite, edginess, and even some treble punch. Of course, it’s to the extent that a $49 single dynamic driver earphone can gain that bite. There certainly is an acute pulse of treble chime when needed without ever sounding discordant to me. I like it. What’s even better is that Kefine didn’t feel the need to add any uncultivated forced resolution or bright overstimulated treble sheen to get some semblance of detail retrieval or satisfying snap to treble notes. Granted, the Klean is certainly not a detail monster, but for something I’d call “musical” first… it’s pretty good in the subtleties. However, to put it in the easiest way possible, the treble on the Kefine Klean is simply well balanced and that balance extends to the technicalities too. I don’t feel the highs on this set are forced to the background, lackluster, or robbed of any vigor and vitality. Instead, I’d say there’s a healthy focus on this region and really it just… works. This is a slightly V-shaped iem after all.

Fine Line​

A few areas where the Klean does well up top, for me, is in the extension past 8k, the subtle airiness, and the timbre in this region. Once again, it all comes together very well and in the end the treble does a good job at replicating the music I’m listening to. The secondary harmonics of a cymbal strike or a hi-hat does not sound splashy to me. Maybe some poorly recorded track will make me a liar but by-and-large the upper treble is not a tizz fest. Cymbals decay fairly naturally in my opinion. Violin has that slight edge that is so savory and delightful while still remaining dulcet and charming to the ear. Perhaps the treble won’t completely engage the treble-heads or the treble junkies, but I do feel they are probably the minority anyways. Not that they don’t matter, they always have EQ. At any rate, I could keep going on and on trying to find different ways of saying the same exact thing; that the treble walks a very fine line seeking to not offend whilst also bringing some solid energy.

Downsides to the Treble Region​

I feel that we’ve covered this but the first thing I’d say is that the treble won’t be considered very good in the eyes of real treble heads. Those treble junkies who love refined and gourmet style treble with perfect note contour, note body, note inflection and note definition. May I also remind you that the Klean costs… $49. Oh, and it’s a single dynamic driver earphone. Just a reminder. I’d also say that those who much more prefer a darker toned treble and are allergic to any vibrance, those folks will also not be purchasing this set due to an educated decision. No sir. However, for the tuning I feel that Kefine did a very nice job on this set and the treble is ⅓ of the reason for that. Again, it all has to come together. Having said that, there are other sets in the price point which I feel simply provide a more contoured and even clean treble. Now I have to add that those sets do not share the same musicality of the Klean or the timbre of the Klean. This cannot go understated. All things considered, Kefine did a fine job on this set.

Technicalities ​

Soundstage​

Soundstage is such a tricky thing to deduce, let alone explain. Anything other than saying “the Klean has an enormous stage” to the reader sounds like it isn’t good. Well, the Klean doesn’t have an “enormous” stage size. It’s about average. No more or no less than most iems in the price point. That said, I truly don’t feel a grand stage automatically means the stage is “good”. It just doesn’t mean that. I’ve heard super wide sound fields in iems where I felt it sounded disjointed, odd, and just bad. What the Klean offers is a stage which makes sense dimensionally. About average height, average width, and average depth. What separates the Klean from other single DD sets in the price point is how the Klean places elements within that stage and how those elements psycho-acoustically get relayed to the brain. It’s hard to explain. Hence why most reviewers simply say… “The stage is good” or “The stage is bad”. I think the Klean presents an average sized stage with a great layout of that stage. Also, other factors do come into play that cannot go untalked about. Stuff like what source you use, the recording quality of each individual track, the genre, the track itself, what eartips you choose, even your hearing are all factors to name a few. Overall, the stage is definitely not bad and never really feels overly congested or closed in.

Separation​

The Kefine Klean is not some technical wizard of a set. It wasn’t tuned to be that. If it was tuned to be that… then Kefine didn’t hit their mark. I say that not in a critical way at all. Actually, I think that the people of Kefine are much better than that because not only did they hit their target… they punched a cannonball sized hole right on center mass. Musicality first! The Klean wasn’t supposed to be this crystal-clear separator of elements within an imaginary stage. It was supposed to be melodic, musical, tunefully mature, yet also fun. Kefine didn’t tune the Klean to dry analytical precision and the Klean are better for it too. So, now that I’ve said all of that I must also interject that the Klean is actually pretty darn good at creating clean distinct note outlines. Even with the slightly more robust, or semi-rich note weight. Especially from the mid-mids on-out. Nevertheless, In the grand scheme of things I’d probably say the Klean is about average to slightly above average against other competitors in instrument separation.

Imaging​

This naturally veers into imaging. Usually, separation and imaging walk hand in hand. Most of the time anyways. However, the imaging on the Klean is a bright spot for me and I do feel that they excel in this area. I find it easy to mentally place instrumentation within the stage. Left to right, front to back. However, with tracks which come across more congested or super bass heavy it is a bit more difficult to place those images. So, there are some caveats. In any event, the Klean will keep a well oriented stage with nicely partitioned-off elements on that stage and it will be fairly easy to discern. Certainly, one of the very nice aspects to the Klean.

Detail Retrieval​

I would say that the Klean has good detail retrieval, average to above average. Though some tracks will be easier than others for the Klean to resolve in a clean manner. Like I said a couple times in this review, the Klean is not exactly a technical wizard. That’s not its fortay. It doesn’t specialize in illuminating the subtleties as it simply wasn’t tuned for that purpose. Having said that, I will also repeat what I’ve said a few times that the Klean is actually very good at bringing out those macro-level-details and even pretty decent with the micro-level-details for what it is and for what it was tuned to be. Definitely it’s a musicality first iem which features a solid timbre and tonality, deeper bass and less intense upper portion of the mix. This combination usually won’t translate to “good at detail retrieval”. However, I cannot say it is bad either. I was actually quite surprised how well the Klean performs in this area. Obviously, with more complicated tracks you won’t get the finest note distinction and definition. Also, just like separation, in bass heavy tracks there will be some slight masking happening. However, for everything else I’d say you won’t miss many details which is great for a set which doesn’t specialize in this area. Overall, average to above average.

Comparisons​

Simgot EW200 ($40)​

I feel that the Kefine Klean Review wouldn’t be complete without a comparison to one of its largest and most well-known adversaries, the Simgot EW200. I reviewed the EW200 last year some time (EW200 Review) and I found it to be a welcome change at the time from what was circulating the market. It really did hit the scene and take over, like a brush fire. Truly a home run for Simgot. Now, the EW200 is a single dynamic driver earphone with 10mm SCP diaphragm and a gorgeous mirror polish housing. Truly a winner in all ways for the price. Let’s see what some differences are with the Kefine Klean.

Differences​

No doubt the Klean is slightly larger, but both sets have an all-alloy build, both built wonderfully, and both look nice as well. The designs are great for different reasons though. The EW200 has the silver polish housing while the Klean has its classy design. Both are very cool. I’d say the Klean is outfitted with better accessories than the EW200 and is a better unboxing too. As far as fit is concerned, both sets seal very well for me, but the Klean is a bit better. I have no way of knowing how your ears will make out here.

Sound Differences​

To begin, the EW200 is flat-out brighter sounding, more electric, more energized with a more brilliant top end and less timbre accurate. The bass of the Klean is deeper & rumblier with rounder notes and more impact. The graph shows them almost the same in emphasis, but in real world testing the Klean simply has more oomph and gusto down low. Looking at the mids, the Klean has the more organic sound, more atmospheric, more controlled midrange. While the EW200 is all about large macro-dynamic energy with a brighter pinna rise, a smidgen better detail retrieval and more airiness. The EW200 has more crispness and crunch in this region compared to the Klean’s better note weight and musicality. However, the EW200 can also come across much more glaring in the upper mids too. Now, the treble of the EW200 is certainly brighter, more brilliant, airier and more open. Having said that, I also feel the Klean has the more talented, controlled, and concise treble region of the two. Where the EW200 can come across splashy with a wilder presence, the Klean sounds cleaner almost with much less chance of fatigue from long sessions. Technically, the EW200 is simply tuned to bring the details to the surface. Leaner note weight, more decisive and transient swift notes usually mean better separation of those notes and in this case it is true. As far as Imaging is concerned, both sets are fairly nice, but the Klean represents a stage better between them both. I’d say they are equal sized stages in width and height, but the depth goes to the Klean.

Final thoughts on this comparison ​

I would say that the Kefine Klean is certainly the more polished performer of the two. Not to take anything away from the EW200. I just find the sound field is cleaner in the Klean. Less rambunctious energy but calmer and more collected. So, it’s a wonder why I’d also say the Klean is the more fun set. Mostly due to the thicker and more booming bass. Still, I enjoy both iems quite a lot and both for different purposes. No doubt both sets are some of the best that the under $50 market has to offer.

Is it worth the asking price?​

Usually when I’m reviewing an under $50 iem that is clearly one of the better iems in the price point then it probably means that I feel it is worth every penny. There’s no “probably” about it… without a doubt the Klean is worth every penny. I don’t even need to go into the reasons why. I probably will though. Anyways, even against all of the competition that I’ve heard (which is a lot) I feel the Klean can stand tall amongst most any set. I never say the word “best” and I will refrain from using it now but most certainly the Klean will be considered one of, if not thee, best in this price point. Again, competition is fierce and also, not everyone reading this is going to prefer the sound signature of the Klean. So of course it won’t appeal to everyone, all the time. However, the Klean represents some of the best tuning that this young brand has completed and if I were Kefine I’d be damn proud of this set.

The Why…​

Because look at this set! Made entirely from metal, clean lines, rounded corners, rounded edges, black-on-gold, minimalist, ergonomic. Looks like it should cost twice as much. The unboxing isn’t bad either. It’s just a nice package for $49. However, of course it’s the sound which makes this set a no brainer at $49. I love what Kefine did with less money than their previous iems. Now, I don’t think the Klean is better than the Delci AE, but I do feel it outshines the Delci OG. It has deep, rumbly bass, but also it keeps tight reigns on that rumbly bass. Very good density, its compact, rigid, and not fluffy at all. The midrange is great for vocals for a V-shaped iem too. Nice presence across the board, good lean-lush note weight, good note density, even some texture at times. Looking at the treble, it is just brilliant enough, nicely detailed, good extension and it comes across nicely controlled for the price too. Great imaging, and nice stage depth helps the Klean to have some dimension, rounded notes, and just a pleasing sound altogether. Folks, this is an unmistakable no brainer for me. Of course it’s worth the asking price.

Ratings (0-10)​

Note: all ratings are based upon my subjective judgment. These ratings are garnered against either similarly priced sets or with similar driver implementations or styles with the unique parameters of my choosing. In the case of the Kefine Klean ratings below, that would be $35-$55 iems of any driver configuration. Please remember that “ratings” don’t tell the whole story. This leaves out nuance and a number of other qualities which make an iem what it is. A “5-6” is roughly average and please take into consideration the “lot” of iems these ratings are gathered against. $35-$55 is a very large sized scope of iems. So, It should be a nice surprise to see a rating above a “9.0”. My ratings are never the same and each set of ratings tells a different story. Each time you read one of my ratings will be unique to that review. Basically, I create a Rating that makes sense to me.

Aesthetic ​

–Build Quality: 9.5 Built very well.

–Look: 9.1 Dope industrial design.

–Fit/Comfort: 9.6 Fit and comfort is great for me.

–Accessories: 9.3 Nice unboxing, above average.

–Overall: 9.4

Sound Rating ​

–Timbre: 9.6 Natural, earthy, organic, semi-rich.

–Bass: 9.2 Heavy, deep, foundational bass.

–Midrange: 9.5 Those creamy & forward vocals!

–Treble: 8.9 Laid-back yet skilled, very nice.

–Technicalities: 8.4 Good techs per the tuning.

–Musicality: 9.7 Musicality over everything else.

–Overall: 9.2

Ratings Summary:​

To summarize the ratings above I’d say the Klean represents a “top class” performance in almost all areas. I rated the Klean against any and all iems of any driver configuration between the prices of $35 and $55. I’ve personally heard most of the better sets in this price point ($35-$55) and also, I own most of those sets too so you can imagine this was a very long ratings period. My method is to take a track which represents each rating, and I go through each set and then the Klean. I listen to a set, then listen to the Klean, listen to another set, then again listen to the Klean. It takes a while. Despite that, it is actually very fun for me. While I think ratings are a waste of time and barely helpful to you, I still have a blast in the process. Still, ratings leave out so many integral nuances and doesn’t account for newer sets which come out after this review. So, take my ratings with a grain of salt. Another thing is this, I feel the Klean is better than a “9.2” in overall sound. However, when you rate per each attribute and average the scores it usually won’t equal what something is worth to you. That said, the Klean did very well in almost all categories which is a huge testament to Collin Yang and the folks over at Kefine. Another thing, a “9.2” is definitely one of the highest scores given out in this price point.

Explain Yourself!!​

I don’t think there’s all that much to explain here. Obviously, some people will take issue with me over a few of these ratings and I wouldn’t blame them. We are all different after all. I’d definitely say the “Midrange” is a Rating that folks may have a problem with, especially since this is not a mid-centric iem and even more so because it is a V-shaped set which means there is a recession of some sort, somewhere. I could see those who want a more forward sound with vocals which seem more on a pedestal then the Klean has. A “9.5” is a very high score. However, I gave it that score due to the very good timbre, the note body and the presence in this area. Actually, that is the only score that seems as though I’d get some words from some of you. Oer than that I’m happy with these scores.

Conclusion​

To conclude my full written review and feature of the Kefine Klean, I absolutely need to thank the good people of Kefine and Collin Yang in particular for providing the Klean for a fair and honest assessment, albeit a subjective assessment. So, thank you very much Collin and thank you Kefine. Truly a special young brand that I do hope great success for moving forward. Also, I thank you, the reader, for actually taking the time out of your busy lives to click the link and check out this review. It means a lot to my partners at Mobileaudiophile.com as each click is of huge importance. We are committed to providing the best content that we can, and we certainly hope it is helpful to you. So, thank you.

Other perspectives​

Now that I’ve thanked you for checking out my review, I also hope that you’d check out some others. There are so many good reviewers out there folks. Just solid people who really do a good job breaking down these products. I hope you’ll listen to, watch, or read dither reviews and perspectives so that you can gain an even better understanding of what you are getting with the Kefine Klean. Folks, we are all very much different. The guy sitting right next to me may have a completely different opinion than I do. Yes, I really enjoy the Klean, but the next guy may not. Or maybe he loves it too. It’s just more info to help you make an informed purchasing decision. I am not the last word on audio, and I do have my own subjective likes and dislikes, so does the next guy. So please click on some more links. Okay, with that all said I think I’ve covered it all. Please take good care, each and every one of you. Stay as safe as possible and always… God Bless!

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