In the Box

• The Klean IEMs
• Detachable 2-pin cable
• Multiple sizes of silicone ear tips
• A compact carrying case
• User manual

While simple, everything included feels thoughtful and of good quality, especially considering the budget-friendly price.

Build and Comfort

Klean’s resin shells are sleek and ergonomically contoured to sit flush in the ear. The faceplates feature a unique marbled aesthetic, giving them a custom look. The nozzles are well-angled, aiding in both seal and comfort. Long listening sessions are fatigue-free thanks to their lightweight build.

Sound

Bass

Klean delivers a warm and well-textured bass response. Sub-bass extension is solid but not overwhelming. Mid-bass is punchy and provides body to instruments and drums without muddying the mids. Bass is more about musicality than raw impact.

• Compared to the Moondrop Aria, Klean offers slightly more mid-bass punch and warmth.
• It is less sub-bass focused than the 7Hz Zero 2, but more organic sounding.

Overall bass is smooth and pleasant; great for those who enjoy a musical low end without excessive thump.

Mids

Mids are slightly warm and intimate. Male vocals sound full and rich, while female vocals retain clarity and emotion. Instrument timbre is natural, with acoustic guitars and pianos sounding particularly lifelike.

• Compared to CCA CRA+, Klean’s mids are less recessed and more natural.
• Not as dry as some Harman-tuned competitors; retains a lush character.

Mids are standout aspects of the tuning, well-suited for vocal and midrange-centric genres.

Treble

Treble is smooth and non-fatiguing. There’s enough sparkle to keep things engaging, but it never veers into harshness. Detail retrieval is above average for the price range, with cymbals and strings sounding realistic.

• Less aggressive than TRN MT4, which can get peaky.
• Not as airy as more expensive IEMs but strikes a good balance.

Treble is easy to enjoy across genres, especially for treble-sensitive listeners.

Technicalities

• Soundstage: Moderate in width, slightly more intimate than wide.
• Imaging: Clean and accurate; instruments don’t blur together.
• Separation: Good for a single dynamic driver—each element has space.

Not a technical monster, but performs very competently within its price tier.

Tuning Philosophy

Klean follows a balanced-warm tuning style, aiming for a musical and fatigue-free listening experience. There are no tuning switches, which simplifies the user experience and reflects a focused tuning philosophy.

Conclusion

The Kefine Klean is a well-tuned single dynamic driver IEM that balances warmth, clarity, and comfort. It stands out in the budget segment for its natural mids and enjoyable, non-fatiguing tuning. While it may not excite treble heads or bassheads looking for extremes, it's a great “daily driver” IEM that most people will enjoy straight out of the box.