Ostry KC06

REVIEW: Ostry KC06


Driver Unit: 10mm high dynamic CCAW Drive unit
Rated Impedance: 16Ω+/-15%
Sensitivity: ≥110dB (at 1000Hz)
Frequency Response: 20 Hz - 25 KHz
Distortion: ≤1% 110dB (20μpa)
Channel balance: ≤1.5dB (at 1000Hz)
Rated Power: 10mW
Maximum Input power: 30mW
Plug size: 3.5mm gold plated dual-channel plug
Cable: 1.35m environmental antibacterial TPU wire

Price: ~$60.



  • 6 pairs (S/M/L) of narrow-bore tips in 2 colors, white and semi-transparent grey
  • 6 pairs (S/M/L) of wide-bore tips in same colors
  • 3 pairs (S/M/L) of even wider tips in semi-transparent color, with red color core
  • 1 soft carrying pouch
  • 1 shirt clip
  • Earguides


Build Quality & Design:

Build quality is decent, nothing outstanding for nowadays standards in this price bracket. If I'm not wrong, the housings implement some titanium material in them. They feel quite sturdy. The cable on the housings entry is not from the rear or down part, but from the sides; short but nicely relieve. The cable is a bit stiff and springy but low in microphonics. The straight plug is quite thin and lacks the necessary relief. The Y-split is very small and there's no chin slider.
The design is quite nice, with a very classy finish, and a tad flashy.
Overall, they could be better built, but fortunately the sound quality makes up for everything.

Fit, Comfort & Isolation:

The KC06's design is quite straight and very easy to fit. Personally, I got better results with the narrow-bore tips, as they are more spherical and better sealing than the wider ones. No tip-rolling was really needed, and aftermarket tips didn't improve the fit, comfort or sound quality. The housings are very, very lightweight and smaller/shorter than what pictures may suggest. Rather comfortable for long listening sessions, but still not up there with the smaller Hifiman RE-400 or HSA Crystal, or even budget sets as the Philips SHE3580, nor as ergonomic as the Vsonic VSD1 or the Moe SS01, but nothing to complain about.
Isolation is a slightly lower than average, at least with stock tips. Aftermarket tips might improve it a tad more.


According to the company, the KC06 model has no need of a burn-in process. Even though, my pair was given a standard 40~50hrs burn-in without serious changes noticed.
Expectedly, with 16Ω of impedance and 110dB sensitivity, the KC06 are very, very effective, and the easiest to drive among every other headphone I ever tried, be it IEMs, buds, over-ears or full-sizes. Even the old Soundmagic PL50 is second to these Ostry.

The overall signature is slightly mid-centric with a noticeable emphasis on the higher regions, mainly the lower treble.

The bass is quite soft in impact and lacks some body. Mid-bass does manage to show some sense of fullness, and doesn't feel as missing or "anemic" as the old RE-0, PL50 and similar, and even richer than the Hisound BA100, but definitely a lightweight contender, especially in the sub-bass extension and depth. However, the low-end quality is another story; it's very tight and detailed and really good in speed. It won't have much rumble but has the more natural decay of the dynamic drivers.

The midrange is the KC06's main attraction. Definitely forwarded, not too thin, not too thick, with great clarity and transparency. Very well-balanced from lower to upper mids, carrying a very nice warmth that gives a better texture and makes them more enjoyable and musical. Moreover, the sound is very open and airy with impressive detail. Vocals are simply at their best, very natural. Fairly intimate and very sweet with lot of energy, without sounding grainy or edgy, and reach a level of detail that is really worth praising, and putting on shame many of the other brands competitors.

The treble is similarly forwarded. Lower treble regions are somehow more prominent than the upper ones, what limits the highs extension a bit. Fortunately, as bright as they can sound, they remain reasonably smooth and easy to listen, never harsh or sibilant, which is always a plus. The KC06 are very resolving and handle complexity without much effort; sure, not as effortless and resolving as the B2 and R-50 (or other TWFK BA 'well-tuned' IEMs), but truly impressive for only $60.

While soundstage couldn't be called small or narrow, it won't have the presentation that less intimate, neutral or v-shaped phones may offer. Even so, they will make sets as the VSD1-S sound more 'closed' and limited.


Surprisingly, despite of being too easy to drive they show quite an improvement from amplification. They're one of the few in-ears that benefit so nicely when amped without showing a hint of distortion. For best results it's preferably to match them with a slightly warmer amplifier/source to give the bass better texture and better body, making the KC06 more 'balanced' from lows to highs. With a stronger, higher-end amplifier they would rise even to a much higher performance in every aspect, matching the well-praised earphones in the $150+ range.

All-in-all the KC06 offer quite a unique sound that reminds me a lot of one of my favorite sets, the Hifiman RE-400, not only in balance and presentation, but also, and more importantly, in quality. The mids are simply beautiful, and they are the only IEM that it's capable to rival the RE-400 special and unique midrange tuning, which is no easy task, even at the $100+ range, and almost impossible in the sub $100. Bass quantity is almost identical, but the Hifiman's sound flatter with better extension on both ends, while the Ostry's give a slightly brighter tone on upper mids and lowest highs. Curiously, the harder to drive RE-400 show almost no gain from amplification, while the easy KC06 improve a lot, even beating them when well powered.


At their retail/street price the KC06 are really worth recommending on sound quality alone. The design is quite attractive, too, and while I can't complain about the fit/comfort, the isolation is sub-par for the daily use. Now, for those that don't need too much isolation and are looking for a silky midrange with beautiful vocals, the Ostry KC06 could be an excellent match that rivals the widely praised RE-400, for a relatively lower price.