Kefine Klean SV Review: Chasing Reference

The Klean SV is Aptly Named

Kefine is a respected Eastern HiFi brand that specializes in building affordable earphones. Their reputation is buoyed by the stellar price-to-performance ratio and refinement of hits like the Quatio and Klean. After a brief detour with experimental sets like the Arnar, Kefine is back on track with a revamped and improved iteration of the Klean, dubbed the Klean SV. That’s what we’re taking a look at today, so without further delay, let’s get into the details!

You can find the Klean SV for sale on HiFiGO for $56.

About My Preferences: This review is a subjective assessment and is therefore tinged by my personal preferences. While I try to mitigate this as much as possible during my review process, I’d be lying if I said my biases are completely erased. So for you, my readers, keep this in mind:

• My ideal sound signature would be one with competent sub-bass, a textured mid-bass, a slightly warm midrange, and an extended treble.
• I have mild treble sensitivity.

Testing equipment and standards can be found here.

The Big Picture

Pros:

• Strong price-to-performance ratio
• Tight, well-controlled bass
• Expressive midrange
• Strong vocal intelligibility
• Comfortable and ergonomic
• Solid accessory package
• Great build quality

Cons:

• Minor sub-bass roll-off
• Quite bright, even with most-restrained tuning nozzle

Key Specs

• Driver: 1x 10mm dynamic
• Sensitivity: 107dB SPL/mW
• Impedance: 32 ohms
• Cable: 0.78mm 2-pin with USB-C OR 3.5mm OR 4.4mm
• Chassis: Metal
• Tuning Filters: Yes, x3

Sound

Graph, for the sniffers. Source: HiFiGO

The Klean SV comes with three distinct tuning filters. These are “damping” nozzles, and each comes with a different thickness of diffusion material inside it. The Klean SV’s tuning nozzles seem to attenuate the 1KHz-10KHz range, leaving the rest of the sound signature unaffected.

The Gold Nozzle

This is the Klean SV’s “treble” filter. It is essentially undampened, allowing the Klean SV to lean heavily into the lower-treble and upper-midrange. This translates to a pretty forward brightness that dominates the Klean’s presentation. Roughly-mastered tracks can sound sharp and unforgiving, so expect to need to tip-roll or modulate volume if you have treble sensitivity. This increase in upper-register presence does give the Klean SV a bit more potential to surface subtle background textures and details, but doesn’t actually improve performance. After permitting my ears time to adjust to each nozzle, I was able to verify that the same details were present on the other two nozzles, just set further back within the mix.

The Silver Nozzle

The Klean SV’s default nozzle is the the silver nozzle. This is the “middle ground” between its treble-centric gold nozzle and warmer, less-dramatic black nozzle. The silver nozzle strikes a great balance between sounding organic and preserving the Klean’s iconic airiness and, well, clean timbre. Its mid-bass has subtle punch that contrasts nicely with its bright and well-behaved treble. The silver nozzle delivers a competent display of layering and dimensionality, rendering well the empty vibes of Midnight City; M83.

While the silver nozzle is indeed less bright and better-behaved than the gold nozzle, it is still sometimes capable of traveling a bit beyond my ear’s treble tolerance. Rough tracks like, well anything by Puddle of Mudd, possess pretty belligerent hi hats and cymbals, pushing their metallic slams further forward than is natural. Properly mastered songs like Father of Mine; Everclear, exhibit no such issues.

The Black Nozzle

The black nozzle is the Klean SV’s “warm” or “bass” nozzle. It reduces the IEM’s share of upper-midrange and lower-treble emphasis the most, bringing them more in line with something you’d get from a “north-of-reference” set. This is my favorite of the three tuning nozzles, so I spent the bulk of my time listening to it.

The Klean SV, with its black nozzles, is much easier to listen to at higher volumes. With its upper-mids and lower-treble tamed, I could increase volume by about 3dB. Higher volume allowed the bass to really open up. Electronic music with deep, sonorous bass lines like Promises (Skrillex Remix); Nero, sound dynamic and rich, with the Klean SV’s driver producing a respectful, but not dominant, amount of sub-bass. The black filter’s warmer, flatter midrange is incredibly organic and allows the Klean SV to really communicate a sense of harmonic weight and fullness. Post Malone’s *One Right Now *drips with richness when played through the Klean SV, contrasting Post’s floaty vocals extremely well. The Klean SV captured a ton of vocal nuance in both Post and The Weekend’s performances on that track, creating a strongly immersive soundstage. The Klean SV likewise performed well when rendering the hi hats and cymbals in Yellow Belly; Thrice. Its ability to communicate metallic tones and textures is excellent and is, in no small part, due to its unusually competent upper-treble speed.

One of the Klean SV’s greatest strengths, when equipped with the black nozzles, is its ability to render a “complete-sounding” track without indulging in over-emphasis. The manic chorus in Hell Raiders; Teminite plays through the Klean SV with a desperate precision, capturing the full weight and substance of the track’s boisterous bass lines without actually producing that much rumble. With the other two nozzles, the hi hats and treble-bound synths in Hell Raiders can sound overpowering a bit sharp, but the black filters allow me to listen at maximal volumes without issue. Really, the Klean SV possesses what I consider to be one of the best-executed interpretations of a “balanced” sound signature in the sub-$150 price point.

Build

The Klean SV features metal shells, though I wasn’t able to confirm which specific metal Kefine used. The SV’s shells feature a fine, semi-matte finish.

On the top of the SV’s shells you’ll find its 0.78mm 2-pin sockets. They set flush with the shell and securely fasten to the included cable.

Speaking of the Klean SV’s cable, the SV is available with either a 3.5mm, 4.4mm, or USB-C termination. I selected a 3.5mm cable, as I typically use my budget IEMs on-the-go and with compact sources. The SV’s cable features a simple twist braid and decently-soft strands of SPC. There’s sufficient strain relief at the base of the termination, so I’m not concerned about long-term durability.

Comfort

Comfort is a metric that relies heavily on factors influenced by your individual ear anatomy. Mileage will vary.

Given its small footprint, the Klean SV was quite comfortable for me. I was able to get a nearly-indefinite comfortable listening session with it, and even had success with it while out on bike rides. The Klean SV’s cable is well-behaved-enough and doesn’t hold on to all that much memory. It’s easy to coil and store within the included case, which is a plus for daily usability.

Accessories

Inside the box, you’ll find:

• 1x Semi-hard carrying case
• 1x 0.78mm 2-pin cable
• 3x Pairs tuning nozzle
• 6x Pairs silicone eartip

For $50, I’d not ask for more than this. You’ve got essentially everything you need for an acceptable experience out of the box. Should you struggle to get a good seal with the included eartips, the Klean’s fairly conservative price point would allow for the purchase of aftermarket liquid-silicone or foam eartips.

I like the Klean SV’s case, as its the perfect size to store the Klean SV, some spare eartips, and even a small dongle, while still fitting in a standard pant pocket. While not exactly the most protective a case could be, I’m not worried about the Klean SV’s metal shells cracking or experiencing significant damage drop a case drop.

Comparisons

Comparisons are selected solely based on what I think is interesting. If you would like me to add more comparisons, feel free to make a request in the comments below!

NiceHCK Tears

The Tears is a new entry-level IEM from NiceHCK. It costs about $30, making it around $25 cheaper than the Klean SV. The Klean SV comes with much nicer metal shells and a thicker cable. The Tears comes with pretty nice eartips, but lacks an included carrying case. The Klean SV also has solid eartips, but they don’t seal as well for me.

Compared to the Klean SV with its black nozzles, the Klean SV is cooler and less-bassy. The Tears has a more-generous lower-register tonality, allowing it to breath a greater degree of depth into dryly-mastered tracks than the Klean SV. EDM is more dynamic on the Tears despite the Klean SV demonstrating a bit more control over its mid and sub-bass. The Tears has a little more upper-midrange presence, but lacks the Tears’s 12KHz spike, instead carrying a little more energy spread throughout the general upper-treble region. The Klean SV has a bit more resolution in the upper register, and extra airiness than the Tears lacks.

Both of these IEMs are great, but the Tears has a simplicity and organic honesty to it that just… works. If I were in the mood for a more detail-oriented, critically-intended listening session, then I’d likely reach for the Klean SV. But, if I’m just listening casually, as I usually do, the Tears is where it’s at.

Kefine Quatio

The Quatio is Kefine’s current flagship hybrid IEM, packing four drivers per-side in all-metal shells. It costs $129, which is roughly double the price of the Klean SV. The Quatio features swappable tuning nozzles and a detachable cable, though the Quatio’s cable is thicker and has a modular termination. The Klean SV has fewer eartips included in the box, but both IEMs were comfortable for me without using 3rd-party eartips. The Klean SV was more ergonomic for me though, achieving better passive isolation and a deeper insertion than the Quatio.

Both the Klean SV and Quatio feature tuning nozzles, but for this sonic comparison I’ll be using the Klean SV with its black nozzle and the Quatio with its gold nozzle. Those are the ones I prefer and use when I listen to these IEMs in my free time. With that out of the way, let’s talk sound!

The Klean SV is brighter than the Quatio, even with the Quatio’s most-bright nozzle and the Klean SV’s least-bright nozzle. The Quatio, in addition to being less bright, has a smoother upper-treble than the Klean SV. The Klean SV’s upper-register is fairly performant for a budget IEM, but has to work a lot harder to approximate the effortless air afforded by the Quatio’s balanced-armatures. The Quatio is warmer, leaning more towards neutrality across the board, but particularly with its lower-mids. Neither IEM is particularly bassy, but the Klean SV has a little more meat to its sub-bass. That said, I’m able to listen to the Quatio’s less-dramatic sound signature comfortably at higher volumes, so I can achieve a similar effective level of rumble by turning the music up a bit. The Quatio and Klean both layer well, but the Quatio pulls ahead during complex passages in busy tracks. Given the major price disparity between these IEMs, that’s not entirely surprising.

The Quatio and Klean SV aren’t competitors, they’re siblings. The Klean SV is more V-shaped, brighter, and oriented towards listeners on a budget that still want clean, pristine sound. The Quatio takes that philosophy to the next level, leaning more-heavily into reference-styled tuning and cranking performance up a notch. If I were on a budget, I’d be selecting the Klean SV, certainly. But if I had the cash to spare and wanted to get a taste of high-performance hybrid IEMs, I’d go with the Quatio, no question.

Kiwi Ears Cadenza II

The Cadenza II is a budget single dynamic-driver IEM from Kiwi Ears. It features plastic shells and a metal faceplate and costs $50, making it about $5 cheaper than the Klean SV. The Klean SV’s all-metal shells have a nicer hand-feel than the Cadenza II’s shells and appear to be more-durable. Both IEMs feature detachable 0.78mm 2-pin cables, but the Klean SV is available in 4.4mm and USB-C varieties while the Cadenza II only sells with a 3.5mm cable. The Cadenza’s cable is siilar in thickness to the Klean SV’s cable, but the Klean SV’s feels a bit nicer in the hand. The Klean SV comes with similar-quality eartips to the Cadenza II, though the Cadenza II lacks a carrying case.

Compared to the Klean SV with its black nozzles, the Cadenza II is slightly warmer. It has a small increase in mid-bass emphasis and a similar degree of sub-bass extension. The Klean SV has a more-forward upper-midrange, but demonstrates a similar amount of lower-treble presence. The Cadenza II has a substantially less-forward upper-treble, however, and doesn’t sound as bright as the Klean SV, even when the Klean SV uses its least-bright nozzles. Both IEMs are airy and demonstrate decent layering capabilities, but the Cadenza II’s greater treble restraint allows it to breath more-easily and naturally. The Klean SV has a smoother upper-treble, though — and this permits it to resolve the metallic timbres of hi hats and cymbals with a greater sense of cohesion and precision. Neither IEM is a clear winner in terms of overall technical performance, though the Klean SV does handle subtle upper-register layering tasks with greater separation and consistency.

Between the two IEMs, I’m selecting the Klean SV for critical listening, but the Cadenza II for casual listening. The Klean SV’s metal shells and improved cable make for a much more premium experience, which is nice — but its higher-strung tuning may not be well-suited for those with strong treble sensitivity, or those that simply prefer darker, less-dramatic upper-registers.

7Hz G1

The 7Hz G1 is a gaming-oriented all-metal IEM featuring a single dynamic driver per-side. It costs about $35, making it roughly $20 cheaper than the Klean SV. The Klean SV comes with a nicer accessory package on the whole, packing nicer eartips, a better case, and a much-improved cable. These aren’t superficial improvements either, and the extra $20 is well-spent on the accessories alone.

Sound-wise, the G1 is a warmer, thicker-sounding IEM. It has a more-forward sub-bass and mid-bass, but exhibits a noticeably deficit in bass control. The Klean SV, in spite of having less mid-bass than the G1, punches harder and sometimes matches it in terms of sub-bass rumble. The G1’s warmer lower-mids synergize pretty well with solo acoustic guitar performances and lonesome pianos, but muck-up layering during busy passages that the Klean SV renders well. The Klean SV’s flatter lower-mids, while somewhat warm in absolute terms, are cooler and cleaner-sounding than the G1’s lower-mids, highlighting both an improvement in tuning and technical abilities. The G1 has a decently-forward treble, but lacks the airiness and precision that the Klean SV commands. The Klean SV renders the edges and decays of metallic percussion with a aplomb, while the G1 often smudges them.

Between the two IEMs, I’m going with the Klean SV. It may be less bassy, but the overall listening experience is still more-engaging. That, combined with many tangible physical improvements and an enhanced out-of-the-box experience make the Klean SV worth the extra $20 bump in price.

Conclusion

The Klean SV is a fantastic budget IEM. Its metal shells are beautifully-made, its cable is comfortable and ergonomic, and its accessories are well-rounded. For less than $60, the Klean SV packs cohesive, detail-oriented tuning into a palatable sound signature. Respectable performance, excellent ergonomics, and a solid out-of-the-box experience make the Klean SV an easy recommendation for listeners looking to take an affordable step into the world of HiFi.

Who This is For

• Treble-heads
• Those that want a neutral-leaning IEM for critical listening
• Listeners that want to experience reference-style sound without the boringness of flat tuning.
• Buyers seeking clean, airy tuning without harshness or sibilance

Who This isn’t For

• Bassheads
• Those that enjoy warm sound signatures
• Listeners seeking traditional V-shaped tuning

As always, happy listening!