I was one of the one of the lucky group of fellas that got in on the KC06 tour (thanks gnarlsagan, Eke2k6, et al!), and I finally got a chance to spend a few hours tonight listening and taking a few notes. I hope to be able to listen more and flesh these out a bit more, but as the rest of my week is a bit insane, I thought I'd go ahead and post what thoughts I've had thus far. The below are basically just my listening notes with a few spelling corrections and clarifications. A few opening caveats:
Prior Knowledge: I specifically did not read anything about these IEMs (other than occasionally reading an offhand remark here or there in non-Ostry threads), so I could come into the review with as little bias as possible. This might be one of the reasons I wasn't initially too excited to review them, and kind of found myself thinking of it like a chore. (Fortunately, my initial listening quickly dispelled this notion.)
Gear Used: Dell Venue 11 Pro (controlled by desktop) > JRMC 19 > Lynx Hilo [HP Out] > headphone extension cable > KC06. I also compared it briefly to the Aurisonics ASG-2 (my daily driver IEM) and the HifiMan HE-6 (Hilo > Audio-gd Master 8 > First Watt F5 clone > HE-6). I fully recognize these are horribly unfair comparisons, especially from a MSRP perspective. But these are what I listen to most often and feel the most comfortable making comparisons with, so hopefully you'll excuse the obnoxiousness of using these as benchmarks.
Reviewer Preferences: I tend to value texture and tone over just about everything else. I am also, apparently, a bit of a treblehead. I listen at significantly lower levels than most people, which tends to mean that the bass is of a lower level than I'd prefer (presumably due to loudness contours). I almost never listen for soundstaging, other than a quick note on whether or not something feels "out of head" or not. I value detail over euphony, but I'm not averse to a touch of euphonic goodness here and there. I listen most often to metal, but have almost psychotically varied musical tastes (I've listed the evaluation songs below). I like pina coladas and getting caught in the rain. My favorite One Direction member is Zakk Wylde. Not sure what else is relevant here.
Pre-Listening Whatnots: I did not receive original packaging, so I can't speak to that. But the first impression of the actual KC06 itself was very positive: these look and feel like very, very nice IEMs. The metal housing doesn't just look nice and feel pleasantly solid; the finish makes it just exude quality. The cable itself also impresses, as it feel like a slightly less flexible version of the Sennheiser IE8 cable, which was a bit of a benchmark for cable quality, as far as flexibility and feel went. Even the little detailing on the splitter looks great and screams quality. (After I pasted this from my notepad, I actually went and looked up the pricing, thinking it was around $100 and looking multiples better than that-- and then I saw it was $60. This has no business looking anywhere near as good as it does for a measly sixty bucks, and anybody who makes less attractive headphones at higher pricepoints [coughETYMOTICcough] needs to take a lesson from these guys on making a high pride-of-ownership IEM, at least from a build and looks perspective.] Damned impressive, overall!
Tips Used: I used the smallest tips (washing them before using, of course), and the KC06 seems to protrude from my ears very little. This bodes well for possibly using as a going-to-sleep IEM. I was originally a bit concerned that a few spots might cause my ears to start hurting, but they never did. (Haven't tried to use them while sleeping yet though). I might try using a different set of tips at some point, but the small ones fit fine and never caused physical fatigue, so I never changed them through this evaluation.
TL;DR Summary: Overall, these IEMs are just extremely impressive at their pricepoint. They do not unseat the ASG-2 in any area in my opinion, which shouldn't surprise anyone, given the discrepancies in cost between the two. They have a beguilingly smooth sound that works really well with some music, and not very well with others.
They tend to sound very, very good during passages where the music is simpler and there is more space to breathe in the track itself, but they tend to get congested when the music gets complex, multilayered and full (see Between the Buried and Me). As a result, they appear to have a fairly narrow genre bandwidth, but are very, very enjoyable given the right musical pairings. Bass is a bit woolly, and recedes into the music when things get hairy, but has the capacity to sound good when there isn't a wall of music in the midrange (see Massive Attack's "Antistar").
One benefit of the smooth sound is how it tends to tame some tracks that might otherwise be fatiguing to listen to (A&P "Terrorbird," any horned instrument that John Zorn is physically proximal to). This is actually not a bad idea with IEMs (which you'll understand if you've ever heard a trumpet blare too loudly and aggressively with IEMs buried deep in your ears). Author & Punisher, in particular, can be extremely fatiguing to listen to for even short periods of time, but I had no issues listening to "Terrorbird." (I actually picked A&P specifically to see if the KC06 could make it listenable, and it passed with flying colors).
For someone who listens to music that benefits from these characteristics, $60 is an absolute no-brainer, and this should probably be on the short list of head-fi'ers looking for inexpensive audio-related gifts for friends and family. If texture, ultimate detail retrieval, and/or metal music are particularly important, however, there are probably better options available... Although maybe not, at $60. That's a bargain for an IEM that does this much right.
Track-by-Track Sound Impressions:
[Note: after taking my notes, I decided to go back and color-code the tracks by whether or not I felt the song paired well with the KC06 in one way or another. A few patterns will become clear by which tracks pair up particularly well and which don't.]
First impressions: popped them in and started listening to the new Opeth album, Pale Communion. The song that was playing was "Moon Above, Sun Below," and my knee-jerk reaction was "wow-- these have a very clear sound!" Midbass has decent impact, subbass is present but slightly recessed, I think. Smooth sound, but not overly so (which is a problem I have with some gear-- the texture of a badass guitar riff is almost never smooth, and gear that makes it seem that way tends to annoy me).
Protest the Hero, "C'est La Vie": vocals seem a bit recessed. Guitar texture is somewhat smoothed over. Bass is discernable, but definitely somewhat woolly. Instrument separation is pretty good. Sound seems a bit overly smooth; although it's not unpleasant, it doesn't seem as accurate as it could be. Something about the bass seems off-- maybe a slight emphasis paired with the muddiness/woolliness? Cymbals sound better than average, but still not as clear and lifelike as ASG-2.
Radiohead, "Technotronique": Bass here is MUCH better, more clear, more impact. Overall, this song sounds really, really good on these. Everything seems distinct and clearly articulated.
Radiohead, "Paranoid Android": Guitars sound a bit more closed-in than they should. Bass again is not as clear. Vocals again slightly recessed. Instrument separation (other than bass) is again pretty good. An enjoyable listen overall. Some of the distant sounds at roughly 2:10-2:15 do sound distant, but they sound a bit fake somehow. Guitar tone at 2:50 is a bit smoothed over again. Top end doesn't seem as open as ASG-2.
Radiohead, "Down Is The New Up": piano doesn't have quite the texture it should. Still a pleasing listen though. Bass again seems better here... Seems like if bass lines are simple and there isn't as much going on elsewhere in the spectrum, it does better-- even though it's still a bit woolly, just not as much as in some other songs. Some fine detail is not discernable.
Masada, "Ne'eman" from Masada: Live in Sevilla 2000: Again sounds a bit confined and damped on the high-end, but the horns sound pretty great. Too smooth, but that can almost be a good thing, as the horns here can be a bit aggressive and biting at times. Soundstage seems congested, although instrument separation isn't bad. These are actually pretty good for listening to horns, as they make them a bit easier to listen to when they would otherwise be a bit biting and strident. Found myself leaving Masada playing longer than some of the other stuff just due to not having to wince at some of the too-upfront horns. Percussion images okay, but not as well as on my speakers (ATC SCM7) or reference headphones (Hifiman HE-6).
Author & Punisher, "Terrorbird": Chose this because it has a very caustic, intensely textured sound, and a strong electronic bassline, which seemed like an interesting mix of things the KC06 does well and things it struggles with. Had to turn the volume on the HPA from the Hilo down as low as it would go, but the song manages not to be fatiguing-- which is impressive, as it is even fatiguing through the LCD-2. Bassline seems a touch out-of-focus, but not terribly so. You can definitely hear a lot of texture in this track, but that's probably because it's just an overwhelming attack of textured sound. It's impressive that these make this track listenable though, as it's pretty rough on some of my other setups. Bass has some impact, but a bit less than it probably should. Listened to the whole track, which I can't often do.
Between the Buried and Me, "Extremeophile Elite": Sound is a bit closed-in and rolled-off in the treble. When the music gets complex, the sound starts to congeal a bit. Again, guitar texture isn't great, too smoothed over. Cymbals are still a bit splashy, but I'd still say they're better than average. Bass gets buried a bit. [At this point, I took a break, got some more water, and got my ASG-2 out to compare. Came back and picked up to the same track where I left off, still listening with the KC06.] My impressions still seem the same-- a bit overly smooth, separation is good when there isn't a lot going on musically. Sound is closed-in and not as extended as I like up top. Little interlude at 4:30 sounds pretty good, everything very well separated and distinct. When guitars kick back in though, it loses something. [Pausing to switch to ASG-2]. On ASG-2, top end is MUCH better, guitars sound much better, texture is back, everything sounds in it's place and rightly proportioned. Sound is still a bit closed-in on top end, but significantly better. Bass is clear, no woolliness. Sound does not congeal together. Sound is just obviously much better with ASG-2. Cymbals sound clearer, more actual sound instead of splash, sounds better. Still not as much detail and texture as HE-6, but better.
Bosnian Rainbows, "Turtle Neck": [ASG-2] Had to turn volume up quite a bit from prev track. Sound seems a touch dark, maybe it's the Hilo, cable, or adapter? [Switch back to KC06]. Actually sounds really good on this track. Guitars seem pulled forward slightly vs ASG-2, which is not what I expected. Sounds more open than I'd anticipated. This seems like a good pairing w/ KC06. Bass missing a bit of impact, but not bad. Vocals sound good. Instrument separation is good. Cymbals sound more like splashy static than they should. Decent sense of space to the sound. Actually started singing along with it at one point. Not a perfect pairing, but a very good one.
Juana Molina, "Dar (que dificil)": Bass was a bit muted at first, got proper pop once I turned volume up a bit. This sounds good! Music is very rhythmically engaging. Instrument separation is good. Tonality sounds good, if not quite spot-on. Sounds good when there are multiple layers, everything well articulated. Perhaps still a bit closed-in sounding up top, but not objectionable, and not really a big deal here. This is another good pairing. The smooth sound works well with her vocals. When music opens up at 4:10, sounds really good, really engaging. Kind of hard not to bob your head with the music on this one. Have no urge to move to another song, good sign. This IEM seems pretty clearly limited in a genre-bandwidth way, although it works quite well with some music.
Mastodon, "Chimes at Midnight": Made the mistake of not turning down the volume before the track started, and this track is just too friggin loud (who the #@$ mixes and masters this stuff these days? Jesus...). Turned Hilo down as low as it would go again. Guitar tone actually seems a bit better than I anticipated, sounds pretty good. Cymbals are really splashy. I kinda thought this would sound like crap, but it's actually pretty good. As with all the metal songs so far, the bass gets buried beneath everything else. Chorus at 2:25 sounds pretty good (cymbal taps sound better, guitar sounds good), although bass is still hard to distinguish. Much better than I'd thought it would be, overall. Instrument separation (other than bass) is good. Started singing with this one too (although that's at least partially due to the fact that this is just a killer song). Sound at 4:57 when it goes back to slower, more open theme is good, but guitars lose some of their texture for some reason.
Massive Attack, "Antistar": Time to turn the volume back up. (Damn jacked-up metal volume levels). Same thing here, when I turn up the music a bit, the bass impact gets noticeably better. Wow, this sounds pretty great, actually. Vocals sound really good, instrument separation is great. Music is a touch less euphonic than it probably should be during chorus, but not badly so. Bass could probably stand a bit of a boost here, but still sounds good. Not exactly taut, but not loose and woolly either, thankfully. Snare hits sound good and open at times. Strings at 4:22 sound good, but aren't as enveloping as they are on other headphones and IEMs. Sounds a touch distant, but not overwhelmingly so. Found my mind wandering a bit, but that's probably to be expected (I often listen to this as I relax before going to sleep). Sounds well-separated, enjoyable. Good pairing overall here.
Massive Attack, "Angel": Bass impact is definitely less than normal. Sounds muffled and closed-in overall. Bass is a bit woolly here too, which I didn't expect, but it isn't nearly as bad as on some other songs. Also sounds a bit distant. Again, misses a bit of the euphonic enveloping that some other headphones/IEMs have that would work well on this track. This doesn't sound bad, exactly, but it's definitely not as good as I imagined it would be. This IEM seems to like to defy expectations (apologies for the annoying anthropomorphism here). Guitars are a bit smoothed-over here too.
Alice in Chains, "Heaven Beside You" from Unplugged: Sounds pretty good! Sounds less muffled than some previous tracks. The two vocalists are a bit better delineated than on some other headphones I've heard. This isn't the best I've heard this track, but it's darned enjoyable. Cymbals are still a bit splashy. Instrument separation is good. Bass isn't nearly as buried here, much easier to pick from the mix, although it's still a bit woolly. Bass doesn't disappear during more full-sounding passages like with other tracks. I can see someone listening to this track really liking these IEMs. Doesn't sound as real as my recollection of listening to these through the ASG-2, but still sounds good.
Nine Inch Nails, "Discipline": Music is kind of congealing here again. High hat sounds a bit static-y. Bass line is a bit buried again. Drums in this song typically have a really noticeable impact, and that impact is muted significantly here. I would have imagined this would be a better pairing than it is. Doesn't sound terrible, but it could sound a lot better. Song doesn't quite sound right somehow, although it's subtle. Guitars are again overly smooth. When there's a lot of texture around 3:30, it just sounds like noise. Not a great pairing, although it doesn't sound awful by any means.
Nine Inch Nails, "Copy Of A Copy": Better pairing already. Bass is easy to distinguish, sounds tighter. Whatever the little sounds are at 0:37 sound good, easily distinguishable, and sound like they're moving around a bit in the soundstage. Bass impact could be better, but it isn't bad. Deeper bass seems MIA or very rolled off. Well separated and articulated sound. Never sounds congealed, this would be a good demo track for these IEMs. When music kicks in at 3:05, sounds really good. Only problem on this track is bass is a little underwhelming. Even when there's more midrange synths at 4:20, doesn't get homogenized, everything still distinct. Great track for these!
The Omar Rodriguez-Lopez Quintet, "Melting Chariots": Sounds very pleasant, although a bit too smooth for my tastes here. Still engaging, as this is a pretty great track. Horns aren't strident in the slightest (as they shouldn't really be here). Separation is quite good. Another good pairing. When things quiet down a bit at 1:55 and afterwards, sounds great! When things get more complex at 2:58, sound does not homogenize, everything still very distinct, nice! Again, horns sound really good, if just a touch too smooth.
Masada, "Bith Aneth" from Masada: Live in Sevilla 2000: Again, pleasing sound. Horns are pleasant and aren't biting, even when they get quite a bit louder than everything else. Bass sounds pretty good here, if not the most taut or clear I've ever heard. Music here holds up well, another good pairing. For someone who likes live jazz, this would be a great track to show off the KC06 sounding really good. Horn is definitely sharper on basically everything else I listen to regularly, but here that almost works in favor of the KC06, as it can be too much to handle on more revealing gear. Music has the right feel to it, even if it's less open feeling than on my speakers and HE-6. Horns aren't even caustic when they kind of try to be (4:34ish). Doesn't sound as "live" as it should, but still sounds really good. Probably because it doesn't sound particularly open? This is music I'd enjoy listening to on the KC06 if I owned it. No real urge to go to something else musically, even though I know this is not the most accurate rendition of the music.
Opeth, "Eternal Rains Will Come": Sounds good, if not particularly well textured (a bit over-smoothed again). Separation is really good, no congealing here. Having listened to this most recently (and extensively, thus far) on the HE-6, I know that there's significantly more texture and microdetail to be had, but if I didn't know that, I'd be really impressed with the sound here. It sounds quite nice, and when the tempo picks up and the music kicks back in around 2:35, it's really engaging. Vocals sound really good, you can again separate the backup vocal tracks from the main one easily. Bass is slightly buried, but not annoyingly so.
Opeth, "Cusp of Eternity": If I hadn't heard this track on the HE-6, I'd probably be blown away. Sounds really good!! Not much to add that hasn't already been said, but I chose to keep listening to the Opeth album rather than take them out, which is a good sign!
Opeth, "Moon Above, Sun Below" [switched to HE-6]: Sounds much more "right." Cymbals are just worlds better, not splashy but actual instruments with tone. Everything in it's right place, tone and texture are there in full force, vocals sound basically perfect, etc. This is the way music was meant to sound....
That's what I've got for now. Hopefully I'll be able to do some more listening and try pairing it up with other amps as well. Lemme know if anyone has questions (or if, in my zeal to avoid prejudice, I missed something important about how to get the best sound out of these). Thanks guys!
Edited by Theogenes - 7/20/14 at 8:57am