KEFINE Klean

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.


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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​

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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.

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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.

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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!

​

The Kefine Klean IEM steps forward as a grown-up iteration of the popular Delci model. It retains the playful energy that made the Delci a hit, but adds a layer of polish, resulting in a more balanced, refined sound that suits listeners looking for both excitement and control. In this review, we'll explore how the Klean’s sound profile, build quality, and technical abilities stack up, offering insights for those who crave an IEM that bridges excitement with precision.

Whats in the box? here is my quick unbox video:

I use the silver tuning nozzle for this sound impression.

Subbass:
Right off the bat, the Klean introduces a more controlled and refined subbass compared to the Delci. It's tighter, less boomy, but still present enough to add weight and depth to tracks that call for it. Where the Delci could feel a little loose at times, the Klean pulls things together, offering a more focused, impactful rumble that integrates smoothly with the overall sound signature. For bass enthusiasts, it may not overwhelm, but for those who value texture and detail in the low end, this is an upgrade.

Midbass:
The midbass sees a notable improvement in punch and clarity. Kefine has managed to add definition here, creating a midbass that hits harder but with more precision. This adds a sense of liveliness to drums and bass guitars without causing muddiness in the lower mids—a delicate balance that the Klean navigates well. If you found the Delci’s midbass a bit too soft or lacking in impact, the Klean will come across as more engaging and articulate.

Midrange

Lower Mids:
One of the excellent features i find in Klean is its treatment of the lower mids. They are lush and natural, presenting a warm foundation for vocals and instruments. There's a richness here that feels inviting, with male vocals and instruments like acoustic guitars taking on a pleasing fullness without becoming overly thick or too heavy sounding. The balance between warmth and clarity is well-executed, making the mids feel substantial yet uncolored.

Upper Mids and Vocals:
Where the Klean really distinguishes itself is in the upper midrange, especially when it comes to female vocals. These are pushed slightly forward, with a brighter presentation that brings out vivid details, while still sounding natural and not overly sharp. This makes the Klean an excellent choice for vocal-heavy tracks, where you want that extra bit of clarity and separation without sacrificing tonality. Instruments in this range, too, benefit from this tuning, sounding more lifelike and engaging.

Treble:
The treble on the Klean is balanced, offering just the right amount of sparkle to keep things exciting without crossing into harshness. There’s a noticeable improvement in how the Klean handles the upper treble compared to the Delci. While the Delci had a splashier, more extended treble, the Klean dials things back slightly, resulting in a smoother, more refined presentation. The roll-off in the upper treble is subtle but contributes to a more relaxed and less fatiguing listening experience, particularly for longer sessions. For those who found the Delci’s treble a bit too splashy, this will be a welcome change.


Left to Right: Kefine Klanar, Kefine Delci, Kefine Delci AE, Kefine Klean






Technicalities, Soundstage and Black tuning nozzle.

Imaging and Separation:

The Klean takes a lot of what made the Delci great and elevates it, especially in terms of imaging and separation. The Klean edges out the Delci slightly in imaging, giving each instrument its own defined spot in the soundstage, everything feels properly spaced and klean There’s a clarity here that really highlights the Klean's more mature tuning—nothing ever feels crowded, and every detail shines through with precision. For a single dynamic driver, Kefine has really nailed it, delivering a refined and coherent performance that feels impressive.

Soundstage:

The Klean does take a small step back compared to the Delci. The Delci had a slightly larger soundstage, offering more roominess and depth. That said, the Klean still provides an impressive stage, just a touch more intimate. It creates a sense of closeness that works well for genres like jazz or vocal performances, where intimacy adds to the emotional impact.

The black nozzle, on the other hand, extends the treble just a bit further, adding a touch more airiness to the top end. There’s an additional sense of openness that enhances the perception of space around instruments, particularly in tracks with a lot of high-frequency detail. This extra airiness adds a more energetic feel to the upper treble without sacrificing control. If you enjoy a slightly more open, airy treble, the black nozzle offers that extra shimmer while maintaining the Klean’s overall refined signature.

Both the silver and black nozzles offer tonal variations on the Klean’s already stellar sound, allowing you to tweak the presentation to your liking without altering the core signature.

In tecnicalities both nozzles maintain the Klean’s strengths in precision, layering, and resolution. There are no major trade-offs here, meaning you won’t lose out on detail or clarity when switching between the two. The black nozzle’s forward mids and airy treble might give the impression of a wider stage or more detail, but these are more tonal differences rather than technical leaps.

Final Thoughts

The Kefine Klean is a clear and deliberate evolution from the Delci. While it maintains the fun and lively sound that made the Delci popular, it does so with a level of sophistication and balance that makes it more versatile and refined. The tighter subbass, punchier midbass, and brighter, more detailed upper mids all point to a tuning that has matured. Add to that a more rounded controlled treble and strong technical performance, the Klean positions itself as an IEM that can handle a wide variety of music with ease.

And for those who loved the Delci but are looking for something more grown-up without losing that sense of excitement, the Klean is an excellent choice. With its balanced yet engaging sound signature, the Klean proves that refinement doesn’t have to come at the cost of fun—it just makes it more enjoyable.

Hifigo link:
https://hifigo.com/products/kefine-...WBlgQAgREaf87xngcA_aem_HA8I0gD4fDedx_imWv_MlA

Amazon Link:
https://www.amazon.com/dp/B0DK4WR4F...xJNFUvI9wEu2Q_aem_dEP4Q3b3JLNtr5L657wQow&th=1

Introduction​

Kefine is already well known for the Klanar, the Delci and the Delci AE, and they have just launched a new product: the Klean. In this review, I am going to speak about this new product and compare it with some other products from other brands.

Disclaimer: the Kefine Klean were sent to me by Kefine so that I could write an honest review. This review represents my personal opinion on the set, it isn't promotional or paid content and I don’t get any revenue from the sales of this product.
At the time of the review, the Kefine Klean were on sale for about $49 at Amazon US, Amazon JP, HiFiGO and Aliexpress.

Click to expand...

Technical Specifications​

• Driver Configuration → 1 x 10mm DLC Dynamic Driver
• Impedance → 32 Ω ± 15%
• Spec-sheet Frequency Response → 20Hz-20kHz
• Nozzle Diameter (widest point) → 6mm
• Sensitivity → 107 ± 1 dB
• Cable → 1.25m detachable silver-plated copper cable with 0.78mm 2-PIN connectors
• Plug Type → 3.5mm

Packaging​

The packaging of the Kefine Klean is rather sample and contains:

• The Kefine Klean
• The detachable cable
• One set of silicone tips
• One pair of different nozzle filters to tune the sound
• Carry case
• User manual

I would really like companies to include at least two sets of different tips, one set isn’t enough in my opinion.

Design, Build Quality, Comfort and Isolation​

The design of the Klean is… “clean”: the metal shells are superbly crafted and are painted in black color. The faceplate only shows the KEFINE brand logo, providing for a minimal design (just like every other KEFINE’s set).



The nozzles are interchangeable and the black ones can be used to fine tune the earphones to a brighter and more “forward” signature.



The earpieces are very comfortable, the nozzle is long enough to grant a decent insertion depth and even though the stock tips aren’t enough to do some proper tip rolling, the fit is already pretty good with them. The earpieces are slightly heavier than average but they are built to last.
The isolation from external noises is average.

Cable​

There are some other brands who include a slightly better cable in the box, but the Klean come with a stock cable that is perfectly in-line with the price range.

Sound​

GEAR USED FOR THE TEST

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

Do they need an amplifier?
No, an amplifier is not strictly needed. An amplifier slightly tightens the low-end but it’s not a night and day difference since the driver is already quite efficient.

Sound signature
The Kefine Klean are U-shaped.
The description of the various frequencies will be based on the stock silver nozzles, whereas at the end of this section you’ll also find out what are differences with the black nozzles.

Lows
The sub-bass and bass are forward in the mix, with proper punch, extension and control. The bass is of good quality, and even though not the punchiest out there, it’s still impactful enough to grant a good reproduction of most tracks, even those that focus on the low-end dynamics.
It’s not a basshead set, but those who love some added bass will definitely like the Klean.

Mids
The midrange is slightly recessed, with more focus on female vocals than male ones. Male vocals and acoustic instruments still have proper weight and warmth, which is good news considering that on most U-shaped sets they lack depth and presence.
Female vocals are spot-on, energetic, lively, never shouty, providing for very enjoyable sessions with female singers’ tracks without becoming fatiguing.
It’s not a set for those who like an uncolored and neutral reproduction, but those who like some coloration will certainly love the way the Klean do it.

Highs
The highs are lively, they pack a good amount of detail, and the general tuning of the upper range isn’t neither aggressive nor fatiguing. I think it’s the type of low-end that will fit most listeners provided that you like a very soft touch of added energy and spice. The upper treble has decent extension too, yet without becoming fatiguing or artificial.
There isn’t any kind of sibilance too, which is great news.

The soundstage is well rounded with nice width and average depth and height. The imaging is very good too for the price range and so can be said for the overall layering.

BLACK FILTERS vs SILVER FILTERS
Pretty easy: the black filters increase the upper mids and the treble, improving the overall energy and the detail retrieval, and slightly reduce the low-end presence. I personally find them a bit too aggressive for my taste, the silver filters make them a lot more balanced, natural and pleasant.

Some comparisons:​

Kefine Klean vs Kefine Delci
The Klean is basically a cleaner and more balanced Delci: slightly more lively and airy female vocals, a tad less treble “spice” due to less emphasized mid-treble and a softer upper-end roll-off. The result is a more correct reproduction of vocals and more coherent sound along the spectrum.
Technicalities are 90% identical, but the Klean has a touch less soundstage width and slightly more precise imaging.
The build quality is good on both sets, but comfort and isolation are better on the clean, also thanks to the thicker shell that provides for a deeper and more stable insertion in the ear canal. The cable is not that different even though Klean’s cable looks a bit better, and the overall tips’ selection isn’t that different.
I’d say just get the Klean since it’s a more mature and more refined Delci, that’s all. If KEFINE told me that Klean’s driver was the same used on the Delci, I wouldn't even read the specs and I would believe that since the technical prowess is quite similar. If you already have the Delci, instead, I would not buy these: there’s not enough difference in performance to justify the expense for the Klean.

Kefine Klean vs Sivga Que
The Que are slightly less U-shaped than the Klean, with inferior end-to-end extension and more forward mids. The two don’t share much, but we could sum-up the comparison by saying that the Klean sounds overall more engaging and lively with a fuller low-end. They also sound a bit more technical and snappier than the Que. If the Klean will be sold for a lower price, then the Que could experience some hard times.
The imaging is better on the Klean, whereas the soundstage is of similar size.
Build quality is good on both, the Que come with a better stock cable and a wider tips’ selection while the Klean provide for better isolation and comfort.

Kefine Klean vs Truthear HEXA
Completely different sound approach: respectively U-shaped and fun-oriented vs neutral and analytical.
The Klean have more bass and sub-bass, with better punch and note weight, the lower midrange is a bit more recessed than on the Hexa and the upper mids are slightly more controlled than on Truthear’s set. The Klean are slightly more natural and vivid up-top even though the Hexa carry some more informations. Overall the Hexa are slightly more analytical sounding and more sterile, whereas the Klean are still quite competent while never sounding boring or sterile at all.
Imaging is good on both sets, stage is a bit more spacious on the Klean.
The build quality of the Klean feels superior even though the Hexa are built very well too. Klean’s stock cable is better. Comfort is good on both sets, whereas the isolation is a bit better on the Hexa.

Final Thoughts​

The Klean are well-rounded and competent IEMs, and they are actually what the Delci would have been if Kefine had applied a few refinements before releasing them. But this is not a bad news, and instead really shows how Kefine has listened to reviewers and users in order to improve a product that already offered a lot for the asking price.
It’s hard to go wrong with a well-tuned set like the Klean, and the price is spot-on for what you receive (except for the fact that I would have liked to see a few more tips in the box).

Another strike (more like a spare in this case, since they had already done a good work with the Delci) from Kefine, hopefully they’ll keep working like this.

Kefine Klean Review​

Introduction​

Kefine made a strong entry with the Delci, an IEM that showcased the brand's ambition through solid build quality and a design that opted for a more refined, non-resin look. Today, we have their latest release, the Kefine Klean—an IEM that maintains the brand's commitment to a robust, full-metal build with a modern aesthetic. Let's dive into what makes the Klean stand out.

Unboxing​

The Klean comes in a clean, minimalist white box with a central render of the IEM. Much like the Delci, it’s a straightforward, no-fuss package that serves its purpose well. On the back, you’ll find the usual specifications.

Inside, you’re greeted with the IEMs, a small accessory box, and a carrying case—sturdy enough to be a makeshift mini soccer ball in a pinch. Inside the case are a selection of eartips and two interchangeable filters to tweak the sound signature.

Build Quality​

The Klean’s design combines sharp angles with softer lines, giving it a sleek, six-sided faceplate that feels sturdy in hand. This design choice is both practical and stylish, offering a no-nonsense aesthetic with a comfortable fit.

The nozzle incorporates interchangeable filters, which add versatility to the sound profile. Rather than swapping the entire nozzle, you simply change the tip where the filter sits. The stock silver filter offers a classic V-shaped signature, while the black filter introduces more upper mids for an airy feel. In this review, we’ll be using the stock silver filter.

The Klean features a 2-pin connection, with a twisted silver-plated copper cable ending in a 3.5mm jack. The cable is impressively solid for its price, easily a step above many budget options.

Comfort​

The simple, ergonomic design of the Klean makes it comfortable for extended use, with no awkward protrusions or bulky angles. The nozzle is reasonably sized, and the cable is manageable, adding to overall comfort. Long listening sessions are easy to enjoy with the Klean.

Sound​

Kefine’s previous model, the Delci, established the brand’s tendency toward a V-shaped signature, offering good price-to-performance value. The Klean refines this approach, dialing up the sub-bass and upper mids to create a more engaging sound without sacrificing balance. With a single 10mm dynamic driver featuring a diamond-like coated diaphragm, the Klean achieves a natural, cohesive tonal character.


The interchangeable filters allow for flexibility: the stock silver filter delivers a classic V-shape, while the black filter enhances upper mids for an airy, slightly lifted profile.


Bass
The Klean has a sub-bass-focused presentation that’s deep and punchy. It excels at delivering rhythm and pulse, making it an engaging listen. While sub-bass takes the spotlight, mid-bass is present enough to add warmth without muddling the sound. Kick drums have a balanced weight and quickness, allowing for a good balance between energy and smoothness.

Resolution in the bass range is impressive for the price, with a nice blend of impact and subtlety. Dynamics are average, and a touch more liveliness could enhance the experience.

Midrange
The midrange performance varies with filter choice, mainly in the upper mids, but the overall tonal quality remains consistent. With the silver filter, the Klean steers away from an overly elevated upper midrange, opting instead for a smooth, balanced response.

Testing with Yorushika's "Sunny," the Klean handles the guitar riff's creamy tone beautifully, preserving the signature chime of single-coil pickups. Vocals have a natural warmth, avoiding a thin or tinny feel. Midrange resolution is solid, keeping up well with its competitors.

Treble
Treble on the Klean has a pleasant balance, with enough air to create a good sense of space without any harshness or sibilance. While V-shaped tuning often runs the risk of sounding overly dark, the Klean manages a balanced treble presentation that remains clear and crisp.

Soundstage

• Width and Height: The Klean’s soundstage is average in terms of width and height, creating an even, comfortable listening space.
• Depth and Positioning: While not exceptionally deep, the Klean’s tuning offers good positioning, aided by a well-handled treble. Dynamics are average, so it lacks some depth, but overall positioning is solid.

Comparisons​

VS Simgot EW300
The Simgot EW300 combines a dynamic driver, planar driver, and piezoelectric tweeter, making it more complex than the Klean’s single dynamic setup. While the EW300 excels with elevated upper mids—ideal for female vocals—the Klean’s cohesive tonality and versatility make it easier to enjoy across genres.

VS NF Acous RA15
With a similar metal chassis and single dynamic driver, the RA15 offers high resolution and elevated upper mids, making it ideal for those prioritizing detail. The Klean, on the other hand, has a smoother, more approachable tone that may appeal to a broader audience.

Likes and Dislikes​

Likes:

• Solid build quality and sleek design
• Easy-to-enjoy V-shaped tuning
• Versatile filter options
• Comfortable for extended use

Dislikes:

• Average dynamics; could benefit from a bit more excitement
• Basic packaging, though serviceable

Final Ratings​

• Packaging: Basic, functional – 6
• Bass: Punchy sub-bass with smooth mid-bass – 7.5
• Midrange: Natural, smooth articulation – 7.5
• Treble: Airy and well-balanced – 7
• Soundstage: Decent but not outstanding – 6.5

Enjoyment Factor: A-​

For under USD $50, the Kefine Klean offers an accessible, cohesive listening experience with an enjoyable V-shaped signature. It’s an easy recommendation for those seeking a well-built, balanced IEM with good comfort and versatility.