OSTRY KC06 High Fidelity Stereo Inner-Ear Earphones


100+ Head-Fier
Pros: Great Details, Drivability, Design and Fit.
Cons: Isolation, Chin Slider
I bought this little gem online last year and been using it since. It only came with a pouch, 2 sets of tips and earphones themselves.
KC06 features a single Dynamic Driver and a "Vibrating membrane technology"
Sources used: LG V10, iFi Micro iDSD.
Genres: Rock&Metal, Jazz&Blues, Electronic&Dance
Build Quality and Comfort
Build Quality is quite nice for a 50$ IEM. Feels very solid in hand and cable is quite durable. (After nearly 1 year of abuse, it is really!)
KC06's design is simple yet beautiful. It is surely not a usual design and they may seem uncomfortable at first sight but they really are not. They're really comfy and I can even sleep with them. They can both be worn straight down and over-the-ear. One more thing worth mentioning is they're very lightweight for a metal earphone. 1/3 of DUNU DN1Ks. 
The only thing I didn't like is the Y splitter. It could have been thicker. Again, I've seen far worse built earphones priced 5 times more than these.
Sound Quality
Let me divide this into sections and start with Bass, Mid and Treble.
BassKC06's bass is quick, punchy and smooth. Just like you'd expect from a Dynamic Driver. Ostry tuned KC06's bass lightweight. It is not rumble tumble rolling thunder kind of bass. It is "be like water, my friend" kind of bass. Furthermore, bass region never bleeds into mid region. It is very well controlled. Bass resolution is also on par with higher priced iems. Don't get me wrong, compared to a single BA or even Dual BA like Havi B3 or Westone W20, Ostry has pretty meaty bass response. 
Mids: One word. Clean. Ostry did a really great job in mid region as well. Overall mids are very detailed, clarity oriented and bright. Ostry did smoothed upper mid section little bit to avoid sibilance land however KC06's mids can crush any earphone between 50-100$ IMO.
Highs: Prominent, crisp and vivid. Although a bit colorized, I find KC06's trebles pretty good. Ostry managed to tune it a hair below the "hot" area of trebles. No one wants to go to sibi-town of course.
Some may find treble little too much for their taste, but without this kind of tuning ostry wouldn't be this revealing/detailed. 
Soundstage: Width is alright but, depth is not very good to be honest. Well hey, it's only a minor setback!
Instrument Seperation: Sub 150$ earphone king in this section. It is very airy. You won't feel congestion or anything like that. Even when listening to high PRaT tracks. 
Rock&Metal: Quite good. You can definitely listen blind guardian, iron maiden etc without feeling claustrophobic. 9/10
Jazz&Blues: Soundstage comes into play, ostrys could really use a bit more depth but instruments are clear and detailed. 7/10
Acoustic + Female Vocal: Absolutely terrific with KC06. Alanis Moriette, Birdy.. etc. Bliss. 10/10
Electronic&Dance: Quite fun to listen to. Definitely could use a bit more bass authority and rumble BUT with those, perhaps mids wouldn't be this clear. So, I am being generous and rating this 8/10
Driveability: It is very easy to drive. Almost anything can drive these earphones.
Isolation: Isolation is not very good. If shure iems are 10, this would be 6 max!
Last Words
Definitely the king of sub 150$ earphones. Current price is 45$.. Brilliant! 
Disclaimer: I am in no way affiliated with Ostry and this review is my %100 honest opinion. 
It sounds like another RHA MA-750.. Which isn't a bad thing.. They are very detailed and revealing, with that moderate bass.. But never rumbly bass...
nice review!
i have been using ostry kc06 for a year now too..still going strong!
my only con with it is sometimes it can be bit fatiguing, but with sound quality and price like this i shouldn't be complaining :)
 Thank you and yes exactly, they are thin sounding but still tuned pretty nice for a 50$ IEM :)@WhatToChoose 
@sledgeharvy Compared to MA-750, these are less muddy IMO.  MA-750 feels little grainy..
@Blazer39 Thanks! I have 2 more friends with KC06s and they're going strong for over 6 months too! 


An expert on his own opinion.
Pros: Comfortable, Well Constructed, Aesthetically Pleasing, Easy to Drive, Fairly Balanced Sound, Bass Can Be Modified
Cons: Stiff Cable, Average Isolation
This is an IEM that caught Head-fi by storm. Featuring a single 10mm high-bandwidth dynamic, using two patented technologies, Ostry made quite the statement. A company that was otherwise unknown before, actually had quite the experience in creating drivers [over 20 years!], likely for other companies as an OEM. They finally decided to release their own products and while I don't necessarily know the patents involved, I have read that the driver in these carry principles from a moving-iron transducer. This IEM leads the way at it's 60-65$ price, sounding better than anything below it's price range, while competing with stuff that's more than twice it's price. In addition, it hits all the marks, in construction, isolation [average but solid] and comfort, leaving little to fault. It is quite the package and an IEM to be still be recommended for quite some time!
Accessories & Packaging
  Packaging is quite nice, with a great presentation. The KC06 comes with quite the array of tips which are organized with white plastic small boxes [pictured below]. Standard single flanges, wide bore [tip opening] red single flanges (which are identical to those of  the TTPOD T1E), small bore single flanges and gray small bore single flange tips. In addition, you get a pouch, shirt clip and ear-guides. The KC06 is well accessorized, though I would have preferred a small hard case, better ear-guides and shirt clips. Personally, I've had no luck with ear-guides as they tend to slide off while in use and just become unpractical, these are just generic and don't have anything to prevent that. The shirt-clip is a generic one I find in many other IEMs and this type of shirt clip, simply doesn't hold the cable well, so it's rather cumbersome. Overall, nothing to fault here though, you get plenty of accessories, Ostry didn't skimp the consumer here.
Build Quality 
  First off, the shell is made of metal and is titanium plated, so quite scratch resistant! Unlike other metal shells this one feels very light, making it not only aesthetically pleasing, but also quite practical. The housing is gorgeous and puts those of the higher priced Vsonic GR07 to shame. The only drawback is that the back of the housings, with the logo, is prone to scratching as it isn't plated, but it should be quite minimal for the most part. The housings have proper strain reliefs, but I do wish the jack had a better, longer strain relief. I would handle the jack with care, only unplugging from the jack's shell.  Y split isn't protected very well either, but I don't expect much failure here due to the cable's thickness. Cable is protected with TPU, giving it a soft slippery feel, but it's not very supple. There is some cable noise but wearing them over the ear or using a shirt clip rids of that. I do have some issues with the cable tangling and sometimes being hard to manage though. Another complaint is the lack of a chin slider, so finding a way to make your own may be necessary. I've had luck using a thin layer of tape. Nozzle is protected with a metal mesh that is quite sturdy, but be sure to check it once in a while for debris. Overall, the KC06 feels well built and aesthetically pleasing, looking like an IEM that is worth much more, the cable is the only slight drawback here. 
[KC06 also comes in a limited Gold Color!]​
Comfort & Isolation
  The housings of the KC06 are quite small, light and it's nozzle is the diameter of smaller IEMs like the Sony MH1/Tenore. This and the fact that it be worn both straight down or over-the-ear [shown below] makes it quite versatile. I can wear these for hours with no discomfort, using Comply T200 or S200. Heck, I'll say, it's one of the most comfortable IEMs I've used to date! These things simply disappear in your ears despite the metal shell. One of the main factors for their comfort is that all you need is a shallow fit, no need to dig them deeper. 
Isolation is average but quite sufficient for commuting in my experience. The use of foam tips helps it isolate, but don't expect it to isolate like a fully sealed IEM. While the ER4 isolates -43db of outside noise, the KC06 isolates about 15-20db. 
Sound Quality
  The signature characteristic of the KC06 is quite hard to pinpoint. I will say it's generally flat, with perhaps a small tendency of being u-shaped, emphasis on the higher treble and midbass. I can confirm this based on InnerFidelity's graph results. To note, the KC06 proves to have a high quality driver, by graphing with very low distortion, in addition to being well-matched between channels. A shocking feature of the IEM is how sensitive the driver is, it is very, very efficient! This is unlike most dynamic drivers and more like a balanced armature driver IEM. This makes it quite dynamic even with your smartphone or portable player and you won't have any problems with quiet recordings, it can get loud! I have a feeling this has something to do with one it's patents, it is quite nice to have and gives it quite the advantage over many inefficient IEMs like the Zero Audio Tenore, in terms of dynamics. Matter of fact, of all the IEMs InnerFidelity measured, I found only the Dunu DN2000 and Shure SE535 to be more efficient, and those use multi balanced armature drivers. To note, because of their high sensitivity, they may hiss with players that are noisy. 
bass: This is the more subtle portion of it's sound. The midbass is elevated above neutral, but very minimally perhaps 2-3db at most and actually rolls off, starting at about 100hz. The bass is clean, quick, punchy and stays out of the way of the midrange very well, I've only heard similar bass control coming from the likes of Hifiman RE400 or the discontinued Sony EX600. The issue lies in the subbass, the bass simply lacks rumble and authority, those wanting realistic bass thump, will simply be missing it here. In this regard it is also quite like the Hifiman RE400, with about -4db below neutral at 20hz. 
midrange: Midrange is surprisingly reminiscent of the Hifiman RE400. There is a slight bump in the 1-2k region, giving a very small emphasis to higher pitched instruments. Higher in the midrange, the 4-5k region is a bit subdued, making it lack some crunch and bite with higher pitched instruments, but it also prevents it from getting sibilant. \
treble: Here you will find two peaks, one at 7k and another at 10k. Luckily, I found neither to be too extreme, but this where tips play a role. Wide bore or short tips, will accentuate these peaks, making it a bit edgy and sibilant. I chose, Comply T200/S200, whose length helps tame those peaks quite well. I also had luck with Meele M6 biflanges. 
Soundstage is quite big and airy, this and it's dynamic nature gives it a very engaging sound. In addition, placement of instruments is done very well, only high-end hybrid or Balanced Armature IEMs will have noticeably better placement.  Bandwidth is only held back by it's slight lack of bass extension but there's a remedy for that.............
Bass Vent Mod: As shown below, the Ostry KC06 has two vents, which can be covered with tape. Covering the top vent [vent pictured on the bottom] reduces bass, but also creates a peak at around 2k, so covering this vent is not recommended. Covering nozzle vent [vent pictured on the top] on the other hand, boosts subbass, with  a gradual rise starting at 250-300hz. Cover the vent completely and you get a slamming subbass, bassheads rejoice! Issue is that the bass does mask a bit of lower midrange detail so for those wanting more clarity theres an alternative. Simply cover the nozzle vent, but then poke a hole with needle or pin. This will reduce the subbass boost to about half of fully sealed and while I still find it to be a bit boosted above neutral, simply use  S200 and you get a fairly well controlled bass with proper subbass, so I use this configuration. Some may live with the KC06's  stock bass roll-off just fine and may not want a sub-bass boost as it makes it linger a bit more, I personally like the boost with the addition of foam tips as it expands it's range. Graph below the comparisons displays what I perceive the KC06 to sound like stock and modded, in comparison to the Hifiman RE400/RE600 which have a similar sound signature [yes it's a simple microsoft paint line on top of Rin's graph lol]
[Setup: Shallow fit, Comply S200, vent pinhole>iPhone6]
Hifiman RE400 Comparison: Starting with the bass, the modded KC06 simply sounds more filled out in the bass, due to more subbass, while having similar midbass levels. I do find the bass of the RE400 a bit tighter, even compared to a non-modded KC06. Bass characteristics are quite similar when the KC06 is not bass modded as they both roll-off in the subbass, with the KC06 having more upper subbass but rolling off more than the RE400 in the deeper bass.  Midrange is surprisingly very similar between these two in terms of tonality, vocals are presented in a similar fashion throughout the range, which is quite surprising. There is a hint more warmth on the KC06, while the RE400 sounds a tiny bit clearer, but the difference is subtle. Upper midrange they are both a bit laid back in upper midrange energy and get very similar throughout. Get to the treble and the RE400 is a bit soft, subdued and rolled off, KC06 on the other hand has better energy and extension. The KC06 sounds airier and detailed in the higher ranges, making the RE400 sound a bit more closed in, in comparison. Both are quick and snappy throughout the range, but the bigger soundstage and added bass and treble extension give the Ostry a more euphoric feel. Both are very close in performance, but I'll give the slight edge to the Ostry. 
Vsonic GR07 Bass Edition Comparison: The bass edition of the GR07 portrays quite realistic sub-bass, a bit less in quantity compared to a modded KC06, with more realistic sub-bass compared to a stock KC06. The midbass levels are similar, with the GR07BE having a bit more bass control, with the KC06 having a little more warmth, midbass to lower midrange. 1-2k region sounds a bit more refined on the GR07, overall the higher midrange sound similar between the two, with the GR07BE being a wee bit more refined. Get to the overall treble and the GR07BE has two apparent peaks, one at 6k and another at 8.5k. KC06 has peaks at 8.5 and 10k. I found the GR07BE to be peakier overall, with a deep fit and Sony-Hybrid tips I was able to tame the 8.5k peak but the 6k peak remains quite present. With the Comply S200, KC06's 8.5k peak is tamed and the 10k peak became minor. The KC06 has better treble extension, sounding more airy and open in these high frequencies, though a bit splashier than the GR07's treble despite being less sibilant. Overall, the KC06 simply sounds a bit more refined in the high regions with a smoother, more extended treble. Soundstage depth sounds a bit better on the GR07BE, but the KC06 is wider and more airy. To note, the KC06 also sounds more dynamic, overall it's a more engaging sound while being about just as balanced. Hard to pick a winner here, the GR07BE's bass and lower midrange sounds a bit more refined, while the KC06 sounds better in the higher midrange and treble. 
Dunu DN1000 Comparison: Here comes an IEM that gets closest in sub-bass quantity compared to a modded KC06. The modded KC06 still has a bit more sub-bass, but the difference is about 2db at most. The DN1K is a bit  tighter in the bass, but both have good sub-bass thump. Midrange warmth is similar overall but the DN1K's midrange is a bit more forward and clearer, guitar accompanies, were more apparently detailed . With the wrong tips DN1K has a quite the big peak that ranges from 7-10k [typical of TWFK BA drivers]. Using Comply TSX400, the DN1K's peak range becomes narrowly placed at 10k and is tamed. KC06's treble is splashier than the DN1K's which is more mature and refined. Both have similar airyness and soundstage width, though the DN1000 carries a bit more depth. DN1000 also places instruments a bit better than the KC06, though it's relatively close. In the end, the DN1000 sounds like a more mature, refined KC06, but the latter makes quite a battle against an IEM that is more than twice it's price. 
Ostry KC06A Comparison: KC06A said to be an improvement than previous iteration, but it just didn't live to my expectations and here's why. Where I found most improvement was the bass, not only was the midbass a bit more refined, the sub-bass was finally present compared to a stock KC06, though to my taste, I still would have preferred a bit more. Midrange is very similar between the two though the KC06A is a bit more clearer in the lower midrange, so male vocals sound cleaner and crisper. Trouble lies once you get higher up the frequencies. I found that the treble peaks of the KC06 were accentuated on the KC06A, resulting in quite an abrasive midhigh region and treble. I used all the tips that I could but to no avail, refinement up top was lost, though I did enjoy the added treble extension. Simply put, the KC06 will overshadow the KC06A for me with it's more subtle treble and tune-able bass. To note, the vent mods didn't quite work on the KC06A, though I was happy with the bass for the most part. Below is a graph between the two I found on a Chinese site, where the engineer was interviewed. Red is KC06A, Blue is KC06, measurements here are raw, so they are not as how the ear perceives it, but it's helpful is showing the difference between the two. 
  Below is a graph of the KC06 as I perceive it, in addition to the effects of the nozzle mod. To note, the 7k peak here is actually situated at 7.5k in my case and 9.5k is actually 10k for me. These are approximate super-impositions from the InnerFidelity graph with added perception results of my ear, not meant to be 100% accurate but gives a good idea as where they stand. 
             . KC06.jpg
Below is the current EQ I use on the KC06, using Equalizer on iOS. -4db at 100hz with q=.5, +2db at 4k with q=1, -3db at 8k with q=3]. This is with pinhole modded KC06. I find the KC06 to EQ very well!
I am currently on a very tight budget and have just been using these, but have not regretted it one bit and neither have I been tempted by anything in it's price range. That goes to show you, how well this IEM fares for me. Ostry have a winner here, I find the isolation adequate, it's very comfortable, well built and sound is great. Even though the KC06A didn't quite do it for me, I am very curious as to what Ostry have in store in the future!
notable links
KC06 Thread
Inner Fidelity Graph
Ostry Website
Hey, does the T-200 have a larger bore than the S-200? Have you tried the comfort series? What size are you using in the pics?
If I did not want to change the sound (a bit more bass is an exception as long as it does not change mids and highs), what Comply's should I get?
Get T200s, different than the picture but I like those more now unmodded
Paulus XII
Paulus XII
Best review of the KC06. Thanks.
Pros: Very good build, easy and comfortable fit, sturdy cable, clear vocals
Cons: No chin slider, female vocals can be strident
Because I’ve been involved with some review samples with my Australian brethren in the last couple of years, I’ve had the chance to hear some IEMs I’ve been curious about in the last year or so, but haven’t been able to (or inclined to) purchase for myself.

One of these has been the Ostry KC06 – and I’d like to take the opportunity to thank my Ozzie mate Vic for the loaner over the last 4 weeks. I’ve enjoyed the opportunity immensely.

For this review – I have abridged it (compared to my normal reviews) for a couple of reasons:

  1. To cut down on postage costs, the KC06 arrived just as an IEM, with the soft cover pouch, and no tips – so I can’t evaluate the packaging or accessories.
  2. I’ve spent a lot of time with other IEMs in the last month as part of planned reviews for other companies, so my time with the Ostrys has been minimal (I’d guess around 15 hours or so). So this just constitutes my general notes and impressions – rather than a full blown review.

Also – I have grabbed a photo from Penon Audio (to cover for missing packaging and accessory shots). I thank them for having the photo available – and duly give credit at this time.

Read on to find out my personal thoughts on the Ostry KC06.


I was provided the Ostry KC06 as a loaner unit from fellow Head-Fier djvkool. I am in no way affiliated with Ostry - and this review is my subjective opinion of the KC06.

PREAMBLE - 'ABOUT ME'. (or a base-line for interpreting my thoughts and bias)

I'm a 47 year old music lover. I don't say audiophile – I just love my music. Over the last couple of years, I have slowly changed from cheaper listening set-ups to my current set-up. I vary my listening from portable (Fiio X5, X1 and iPhone 5S) to my desk-top's set-up (PC > coax > NFB-12 > LD MKIV > HP). I also use a portable set-up at work – either X5/X1 > HP, or PC > Beyer A200p > HP. My main full sized headphones at the time of writing are the Beyer T1 and Sennheiser HD600. Most of my portable listening is done with IEMs - and up till now it has mainly been with the Fidue A83, Dunu Titan and Altone200. A full list of the gear I have owned (past and present is listed in my Head-Fi profile).

I have very eclectic music tastes listening to a variety from classical/opera and jazz, to grunge and general rock. I listen to a lot of blues, jazz, folk music, classic rock, indie and alternative rock. I am particularly fond of female vocals. I generally tend toward cans that are relatively neutral/balanced, but I do have a fondness for clarity, and suspect I might have slight ‘treble-head’ preferences. I am not treble sensitive (at all), and in the past have really enjoyed headphones like the K701, SR325i, and of course the T1 and DT880.

I have extensively tested myself (abx) and I find aac256 or higher completely transparent. I do use exclusively redbook 16/44.1 if space is not an issue. All of my music is legally purchased (mostly CD – the rest FLAC purchased on-line).

I tend to be sceptical about audiophile ‘claims’, don’t generally believe in burn-in, have never heard a difference with different cables, and would rather test myself blind on perceived differences. I am not a ‘golden eared listener’. I suffer from mild tinnitus, and at 47, my hearing is less than perfect.

For the purposes of this review - I used the Ostry KC06 straight from the headphone-out socket of my iPhone 5S, X5, and X1. I also used my Beyer A200p and also the E11K amplifier, but IMO they do not benefit from additional amplification (in fact it can cause issues as they are extremely sensitive so if your amp has balance issues at low volumes it would be best to avoid). In the time I have spent with the KC06, I have noticed no change to the overall sonic presentation (break-in), but am aware that my impression of their sonic footprint may have changed over time with use (brain burn-in).

This is a purely subjective review - my gear, my ears, and my experience. Please take it all with a grain of salt - especially if it does not match your own experience.



As I explained earlier, all I will document here is what the KC06 normally comes with, and include the picture from Penon. I can’t comment further as I have not seen either the retail packaging or accessory package.


The KC06 are packaging in a black and white retail box with foam inner compartment housing the IEMs. Included as part of the accessory package are 6 sets of silicone tips, 2 sets of earhooks, shirt clip, and soft suede type draw string pouch.


Single dynamic driver inner ear monitor
10mm dynamic driver
Frequency Range
20 Hz – 25 Khz
16 ohm +/- 15%
110 dB at 1 kHz
3.5mm gold plated, straight
1.35m “environmental antibacterial TPU wire”


Borrowed (with due thanks) from Innerfidelity. This coincides a lot with what I hear – good vocal clarity (especially with male vocals), but a dip in the upper mids which does make some of my female vocalists sound hollow and strident. A mid bass hump, but good treble articulation / detail.

The KC06 has what looks to be a mostly metal light weight shell. It’s ergonomically designed to be worn over ear (I tried cable down and fit was troublesome – YMMV). The body is pretty tiny measuring 15mm by 13mm and 15mm in depth from the back of the IEM to tip of the nozzle. The unit I have here has a silver coloured faceplate and dark chocolaty coloured body. There are 2 vents or ports – 1 adjacent to the cable exit, and another one at the base of the nozzle. The nozzle has a good lip, and is mesh covered to protect the driver.


KC06 shell - ports visible

KC06 - ergonomic shaping

3.5mm jack and y-split

The KC06 has extremely good cable relief from the IEM body. The TPC covered cable is shiny, and flexible, but does retain quite a bit of memory. It is microphonic, but this pretty much disappears wearing them over-ear with the cable tucked inside clothing. The Y-split is metal, looks like a letter Y, but has no cable relief at all. It does not have a cinch / chin slider either. The cable terminates in a skinny (smart phone case friendly) gold-plated 3.5mm straight jack. The jack has good strain relief.


KC06 - rear view

KC06 from the front

KC06 from the rear internal side

The L/R markings on the body are a little hard to see, however as the earpieces themselves are ergonomically designed, it is easy to tell left from right, even if not sighted.

Overall the build quality is a very good standard for the cost. I would have liked to have seen strain relief at the Y split, but the cable material does look pretty strong. The missing cinch would be my biggest critique so far.


I have one ear canal slightly different to the other one (my right is very slightly smaller) - so I tend to find that usually single silicon flanges don't fit overly well. I couldn’t try any of Ostry’s tips – so I used Comply, standard silicones from my own collection, and also a pair of L Sony Isolation tips. These gave the best combination of fit and comfort – so they were used throughout the review.


KC06 with Sony Isolation tips

KC06 - shallow fit, but for me a reasonably good seal

KC06 - solid build

Fit is actually pretty good – but it is shallow (due to the shape and design), and I have no issues getting a consistent seal each time. They are also flush (actually recessed) with my outer ear, so wearing them lying down is easy and comfortable.

Isolation with a good insertion and correct seal (for me) is average for a dynamic IEM, mainly due to the IEM ports. With music playing, most ambient noise is well and truly filtered out. These would not be my choice for a long haul flight though.

So how does the KC06 sound to me?


The following is what I hear from the Ostry KC06. YMMV – and probably will – as my tastes are likely different to yours (read the preamble I gave earlier for a baseline). Most of the testing at this point was done with my Fiio X5 as source, no EQ, and Sony Isolation tips.

Tracks used were across a variety of genres – and can be viewed in this list http://www.head-fi.org/a/brookos-test-tracks.

Thoughts on General Signature

If I was to describe the default signature in a few words – I’d choose the words “clear”, “forward vocals” and “relatively balanced”.

The KC06 has a signature which mixes clarity in the lower mid-range with a bit of a mid-bass emphasis, and a nice sparkle in the lower treble. The only issue I have with them personally is a bit of a recession in the upper mid-range which makes some of my favourite female artists sound hollow and strident. It also has a tendency to make a lot of my music sound darker than it is with some of my more regular IEMs.

Overall Detail / Clarity

For this I always use both Steely Dan’s “Gaucho” and Dire Strait’s “Sultans of Swing” as there is a lot of micro detail in both tracks, and the recording quality for both is excellent.

First up was Gaucho, and it is a very nice presentation with everything from bass guitar, keyboards, vocals and sax nicely balanced. There is plenty of contrast, good impact from drums and nice detail from cymbals. Likewise, “Sultans of Swing” displays another excellent sonic presentation, and the KC06 represents Mark’s vocals brilliantly. Bass is really good, and actually reasonably fast and tight. Cymbals are there but not overdone. There is sparkle, but it is also smooth.

Sound-stage & Imaging

For this I use Amber Rubarth’s binaural recording “Tundra”. I use this because it’s a pretty simple way to get comparative data on sound-stage.

It’s usually difficult to get a reasonable stage size from an inner ear monitor. The stage is often quite small / close – with an average impression of space. The KC06 has a very closed in stage with this track, and not at all what I am used to with my regular IEMs. I’m actually quite surprised with this because the actual imaging suffers accordingly with the instruments struggling to find their own space. The violin is a little wider – but overall staging and imaging (for me) is very intimate (and it shouldn’t be).

Next up was Loreena McKennitt’s “Dante’s Prayer” and whilst the presentation was still pretty good, Loreena’s vocals didn’t have their normal magic. Her vocals are pretty close through the KC06, but there is some width with the cello. Again the KC06 struggles with depth for me though. In this track, the applause at the end is so well presented that with some headphones (HD600) I can actually close my eyes and imagine myself in the crowd. With the KC06, the applause is behind me (instead of around me), and it feels detached/impersonal.

Bass Quality and Quantity

The KC06 so far has had pretty good bass response – maybe slightly elevated through the mid bass, but not unnatural or over contrived.

On tracks like “Muddy Waters” by Mark Lanegan, the bass impact is just right, and the vocal presentation (dark and brooding) is brilliant. There is no sign of bass bleed.

Switching to “Royals” and the overall impact is great, with enough sub bass to add a little bit of rumble to the bass guitar and kick drum. The bass delivery is copious but it is controlled, and the KC06 really does well with this modern pop track.

To get a further idea of quality this time, I next played Zoe Keating’s “Escape Artist”. The KC06 presents Zoe’s cello a little more forward than I’m used to, but captures the overall timbre really well.

Female Vocals – A Special Note

I have added this section simply because around 60-65% of my music revolves around female vocals – be it jazz, pop, rock, electronic, or even opera. I’m an unabashed fan. For me the sign of a successful IEM is how successfully it conveys emotion and timbre with my female vocalists. Other IEMs I’ve owned in the past had sometimes struggled with some of the artists I like – and this includes IEM’s like Shure’s SE535 LE (upper-mids on the SE535 LE are quite forward).

I was already fearing the overall “critical listening” results with these after listening to them casually for the first few days. Some artists sounded great (a little darker than I’m used to) but not unpleasant. One of my hardest tests (for my own preferences) is how an IEM handles an artist like Agnes Obel (some of her recordings can become quite strident or shouty if the mids aren’t quite right). Sure enough, the presentation was slightly strident compared to what I am used to, and not really to my personal tastes.

I then proceeded to play my normal medley of other tracks from artists including Christina Perri, Gabriella Cilmi, Florence and the Machine, Feist, Julia Stone, Sarah Jarosz and Norah Jones. For me, it handled most reasonably well – but I couldn’t help feeling that their vocal presentation sounded darker than my normal preference and again that hollowness and stridency reared its head (especially with Perri and Jarosz). It was also pretty unpleasant with Netrebko and Garanca’s “Flower Duet”. I had no problems with Jones and Cilmi though – so it does seem to be a bit hit and miss.

Male Vocals

At the other end of the scale sits a lot of my rock tracks.

The KC06 was very energetic with everything I queued. Clean and clear in vocal presentation, and able to nicely contrast the crunch and edge of lead guitar with very good bass impact. Best of all male vocals sounded right – really natural and full.

Time for what has become my litmus test with male vocals – Pearl Jam. Like the rest of the Rock tracks I’d already listened to, the KC06 was very good with Pearl Jam – presenting Vedder’s vocals wonderfully. Cymbal hits are clear, the background bass guitar is complimenting. The KC06 do Rock well.

Genre Specific Notes

Again for tracks, albums, artists – please refer to this list: http://www.head-fi.org/a/brookos-test-tracks

This is just very quick thoughts on where the strengths and weaknesses lie (for me) with the KC06.

  1. Rock – already covered with the Male Vocal section above. The KC06 does rock (particularly male vocals) well.
  2. Alt Rock – pretty good. Floyd was good – especially vocals. Had the occasional stridency with the guitars upper registers though. My personal preference for PT’s “Trains” would have been for a little bit more brightness, but the bass impact was good.
  3. Jazz / Blues – Hit and miss. Portico Quartet was mostly good, but the sax was slightly off (strident). Bonamassa on the other hand was excellent. Great timbre and tone and good contrast between guitar and vocal.
  4. Rap / EDM – The KC06 shines with these genres for me. The clarity of the vocals along with the impact of the bass is very good.
  5. Pop / Indie – Was very good with most pop, but a little dark for the Indie artists I follow. The KC06 was just lacking that little bit of upper mid-range euphonic sweetness that I love with artists like Wildlight. This is simply my preference at work though.
  6. Classical / Opera – very good with male opera, but not (for my tastes) with female. Does solo piano and cello exceptionally well – but I prefer a slightly brighter IEM for full orchestral.


I covered this in the introduction – but to me the KC06 definitely don’t need any extra amplification. They were easily powered out of all my portable devices, and with the X5 I was often below 30/120 in terms of volume. I did volume match and compare the X1 and X1+E11K, and apart from a slight change in tonality (minimal) there was no real change in dynamics. It was also pretty difficult doing this as I had to have the volume so low on the E11K I was in danger of channel imbalance. The KC06 is exceptionally easy to drive.


The KC06 was a very interesting trial for me, and one I’m really glad I got the opportunity to try. At sub USD 60.00 I can see why they are so highly regarded by many.

They are very well built, comfortable to wear, and reasonably well balanced. Their strengths (IMO) are for most rock, and modern pop, EDM and rap / hip-hop. They provide very good vocal clarity, and a nice level of detail.

For me personally though, I had issues over time with the very forward nature of the KC06 vocal presentation, and also the rather small (depth) soundstage, and the stridency and hollowness of the upper mid-range (comparative recession in the 3-6kHz area). This may not affect a lot of people – but for me and my music tastes, I find it a deal breaker.

For the strengths it brings to the table (particularly for the value it offers), I give it 3.5 stars – but I’d struggle to go higher because of my own particular tastes.

Thanks to Vic for the opportunity to try them. Good IEM – but won’t be on my “to buy” list.

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Thanks Tom - my favourites so far would be the A83 and Altone200.  If you want a cheaper pair which are very good - then the Dunu Titan should definitely be considered, and a new discovery for me (review coming soon) - the Havi B3 Pro 1.  These all have one thing in common - an elevated upper mid-range.
Great review Brooko! It mirrors my own impressions really well (and I also listen to a lot of female vocals) which makes me curious about your impressions on the B3's since they're one of my all time favourite IEM.
Lets just say it took a little while for me to warm to the Havis - but once I did, I really like them.  Enough that despite all the IEMs I have, I'm actually considering buying a pair.  Review should be up this weekend.  They are a real sonic diamond.


twister6 Reviews
Headphoneus Supremus
Pros: detailed sound quality, great design and build quality, accessories
Cons: stiff cable
This is a review and comparison of Ostry KC06 and KC06A in-ear headphones.  http://www.ostry.com.cn/item/detailPage?itemid=28 and http://www.ostry.com.cn/item/detailPage?itemid=29
I get a chance to review and to compare a lot of different headphones some of which represent an amazing value with an OK sound while others have a great sound with a price tag that makes you question their value.  Once I got a chance to listen to Ostry's latest KC06 and KC06A headphones, I knew right away these represent a rare combination of both amazing sound and value!!!  As a matter of fact, these headphones got quickly escalated to the top of my all time favorites.  Let me tell you more why I'm so excited about these.
Due to similarities in packaging and design, most of the review will be combined with an exception of sound description where KC06 and KC06A have their own individual style.
Starting with a packaging, I was truly impressed in how much thought went into its design details.  Everything from a foam padded outer sleeve with a distinct cutout to reveal headphones under a plastic display cover to an etched out spec on the back of it (which unfortunately I wasn't able to capture in pictures due to unique nature of it) and ergonomics of accessories placement inside of the box - represent a great level of pride this company took to showcase their flagship product.  I also noticed that original packaging of KC06 from 5 months ago has been re-designed, and now KC06 and KC06A look similar with an exception of red details of "A" version.
When it comes to accessories, both models include an ample amount to keep everybody happy.  You get a pair of soft earhooks to assist with wearing these wire up in addition to a default wire down, a shirt clip, a soft velvet drawstring pouch where surprisingly KC06A had a wider one (more appropriate in my opinion), a warranty/spec card, and plenty of custom eartips.  Both include a set of S/M/L wide-bore short stem eartips (enhances high frequency) and a set of S/M/L narrow-bore longer stem eartips (more balanced with bass emphasis enhancement).  In addition, "A" model includes a very unique set of S/M/L eartips with a built in filter which I found to enhance bass performance even further.  All these eartips look to be custom made, rather than cheap generic ones, and I was able to achieve a great fitment comfort and the best sound with narrow-bore tips.  But for enhanced sound isolation, since I do have a relatively wide ear canal opening, I settled with my go-to UE900 eartips.
Moving on to a build quality, I was very impressed with what Ostry had to offer.  Unlike your typical cylindrical in-ear shape that sticks out, these have a flat vertical design with a very comfortable fitment.  For me personally, these didn't require any additional adjustment after the initial insertion.  As a matter of fact, you can lie down with these on a pillow and they still feel comfortable.  The body of the earpiece supposed to be made with some lightweight titanium material with a very durable construction.  Both models have a similar pinhole opening at the tip and the body of earpiece, overall have an identical size/shape, and the only difference is the design graphics with a more neutral sort of question mark of KC06 and a more aggressive KC06A with red accents.  The wire is attached to the back/side and gets wrapped in a strain relief which blends with a tear drop shape of the earpiece.
The cable between two models is identical with an only exception of red accent marks on KC06A model.  The cable jacket, though offering a great protection, unfortunately is stiff and has a "memory" effect where after unfolding it doesn't get straight.  I guess it's one of those things you have to live with.  Y-splitter has a very interesting "Y" shape design, and the end of the cable is terminated with a very slim 3.5mm gold plated straight connector.  It has a short strain relief, and I would prefer it a little bit longer considering wear of straight plug.  Also, surprisingly there is no chin slider, though it's not a deal breaker and mostly useful for behind the ear wire fitment.  Furthermore, I didn't sense any microphonics.
But as you know, all these eye-candy design details would mean nothing without a sound to back it up.  Here, both KC06 and KC06A deliver with a top notch performance!  Starting with KC06, I was very pleased to hear a well balanced sound with a touch of mid-centric brightness.  Starting with a bass, you get a great quality with a detailed performance.  I can clearly hear separation of sub-bass and mid-bass, but sub-bass quantity is just there to give sound a body rather than a rumbling to make you feel it.  Mid-bass punch is snappy and quite satisfying to my taste.  The bass feels a step above of the reference performance, and it's pleasantly well controlled within it's frequency range.  Mids are very detailed, clear, slightly upfront but still in great balance with the rest of the sound.  I really like how this performance translates into vocal delivery, very organic, with a touch of brightness, and still smooth.  Treble is well extended, detailed, with enough brightness without being too overwhelming, and still very easy on your ears.  For the comparison, if I consider RE400 to have warm reference sound, KC06 has a balanced reference sound.
Now, the KC06A kicks it up a notch into a direction of a more commercial sound signature with a slight v-shape cut (relative to KC06).  Luckily, they did it a smart way without doing any extreme tuning to kill the mids which sounds a bit warmer in comparison to KC06.  The bass here gets a refreshed quantity of rumbling sub-bass that can even put a smile on some bassheads.  You still get a great separation between sub and mid bass where the later one is on par with KC06 performance.  Bass is still well controlled without spilling into lower mids or the rest of frequency range.  Mids are still detailed but now just a bit recessed to bring up a power of the low end.  I was very pleased Ostry didn't reduce the quality of the mids except for smoothing out some brighter peaks, and just slightly scaled down the quantity while keeping most of the original attributes from KC06.  Treble is still well extended, has a similar crisp performance without any hint of sibilance.  Also, I didn't find any significant difference in soundstage width.  A principal change from KC06 and KC06A is enhanced/additional sub-bass and slightly recessed warmer mids.  As a matter of fact, I'm still on a fence if what I'm hearing as "slightly recessed" could be an effect of enhanced bass and a bit of brightness reduction.
Overall, I was very impressed with everything about these fantastic headphones.  Well, almost everything except for the cable where I would prefer a softer jacket to get rid off that wire memory effect.  Now, when it comes to ergonomics of the design and it's comfortable fitment and the sound signature - both KC06 and KC06A quickly got elevated to the top of the list of my current favorite headphones.  I was actually thinking which one I would like better, and it was a hard decision to make because I enjoy both of them very much, and would highly recommend either.  With a current price of around $60-$80 (newly introduced KC06A is higher in price), these headphones represent a true "giant killer" value in every aspect of their design and sound performance.  Can't wait to see what Ostry going to come up with next!!!
Here are the pictures of individual models.
if i get to choose between the Vsonic VSD3/S and KC06/KC06A which one would be good for Vocals and classical music ;-;
DJ The Rocket
DJ The Rocket
"The cable jacket, though offering a great protection, unfortunately is stiff and has a "memory" effect where after unfolding it doesn't get straight. I guess it's one of those things you have to live with."

Really? The cable on my KC06a must be completely different then, the cable is the softest, most supple cable I've ever had the pleasure to use! It's so nice and soft that cable memory with it would be a joke.

I got mine through Massdrop, maybe that explains the difference? Also I only got one pair of the red screened tips. Still, for the lovely cable, that's a trade I'll make every time!
@DJ The Rocket : you just rehashed 2+ year old review, I'm surprised they still make them :)  And if they do, most likely they revised their design based on the feedback received over 2.5 years since its introduction.  That's very common, and I'm glad they addressed the cable issue because back then it wasn't good.


Member of the Trade: mobileaudiophile
Pros: Balanced but mid oriented with a good bass (for armaure lovers, not bassheads), comfortable, a very wide stage, ultra rich and well designed box
Cons: Plastics under the drivers, cable (looks weird), L and R markings are prone to get erased.
The box is perfect I must say. Many tips and that designed by ... print and all that patented tech. And don't forget the lovely wide soundstage though not 3d.
is this supposed to be a review or what??
A short one, easy to read.
Paulus XII


100+ Head-Fier
Pros: tonaly balanced, good details, comfort, low profile
Cons: cables are rather sucky, isolation
Alrighty I just got the Ostry's this morning. Out of the box they sounded a bit weird... which disappointed me :frowning2:
With a big sigh, I put it in my ears for a bit longer hoping that it would eventually get better.
Aaand conveniently it did
It's like a car in a cold morning when you just turned it on and you gotta wait a bit before driving it.
Build quality:
Very solid 
whoever said the build quality on the KC06 is cheap........ well they were wrong.. you don't know what cheap build quality feels like, VSD1 felt much cheaper than this.
This is not the most rugged IEM i've ever had but this is VERY solid.
The cable is somewhat annoying but it's not the worst. The top half (from Y splitter) tend to keep the bends from the way they were packaged, like the klipsch reference s4i.
Flat cables like the ones on FAD Heaven series or cloth cables like the ones on monoprice/RE-400 are worse, but this cable is not as good as the ones from ATH IM series. 
It also lack a cable cinch making it overall not the worst nor the best but it doesn't bother me
Score (4/5)
3 sizes of 2 different types of tips, (dome shaped [largest diameter at the base] and the egg-ish shaped [largest diameter close to the middle])
shirt clip
small carry pouch
ear guides
score (3.5/5)
When it comes to comfort the ostry's win by miles. I'm not saying the IM70 is uncomfortable, but the KC06 is just far better.
You just put it in with the cables down and it just sits right there very comfortably. The IM70 requires a bit of fiddling around and adjustment of the memory wire before it fits right.
When worn cable up, it is less comfortable because of the ear-guides, but even when worn cable down there’s hardly any microphonics so cable up is a bit unnecessary.
The actual IEM is very comfortable but the cable can be a bit annoying especially since it’s lacking the cinch, this takes off 1 point off a perfect score.
Score (4/5)
The KC06 is really bad in this department. In fact it's so bad that it doesn't feel far off from wearing an earbud. I wore this on the bus on the way to uni and I could hear the bus engine very clearly, it was very distracting. I could hear a phone ringing from the lady in front of me and I could hear her conversation. When I got off and walked, I could hear the cars passing by. 
I would give the isolation a
score of  2/5 
It is only present if you actually tap the cables, otherwise you won't really hear it. The lack of cable cinch also has an effect here
Score (4/5)
Sound :
For about $60 this is truly a giant killer, this is far more enjoyable than something like the RE-400. 
In comparison with the ATH-IM70, I still think the ostry's are a little inferior in terms of sound quality alone (by a little i mean really little). 
The IM-70 is able to pack more punch and reach lower in the bass and has better soundstage.
In my opinion the two have a similar sound signature, but the ostry's are about 85% or even 90% of the IM70's quality.
The bass reaches fairly low, without being bloated or bleeding into the mid range.
It packs more punch than the RE-400 but less than the IM70.
The bass might not be enough to satisfy for bassheads but by no means are this IEM bass shy!
I can only imagine the KC06A being closer to IM70 with how some people describing it with having more bass and better sound stage.
The mid range is very clear and very smooth. It produces quality mids that can be on-par with some $200 IEMs out there. Vocals are rather sweet and lush, not as dry as RE-400
The highs have a bit of sparkle to them without being sibilant but I found them having a bit of grain to it.
They are quite prominent compared to something like the RE-400 but not as smooth as UE700 (with foam) or as piercing as UE700 with silicone tips
The overall sound signature is very balanced! The weakest point of the IEM is probably the soundstage but that is a very minor gripe.
Just because it's the weakest point doesn't mean it's weak at all, by the way.
For $60 I would totally recommend this, if isolation is not an issue. To me this is like a more engaging, more fun and cheaper than RE-400.
This should for sure be the first recommendation for a sub $100 IEM, hands down
Thanks...I think you expressed my impressions exactly! These stop me from wanting to spend hundreds of dollars on other iems and just have fun at these prices...