I just became the proud owner of a pair of these ES10. Also own the A900X, another fine Audio-Technica product, this is definitely an upgrade.
They just listed these for $325 equivalent brand-spanking new on amazon.co.jp, and I was about to pull the trigger, but then I found some used (but very nice shape) that I ultimately picked up for $210 equivalent.
I was blown away by the dynamic range of these headphones, while maintaining great separation and performance all across the spectrum. Wow! Here's my brief impressions thus far:
Test tracks: Violent by 2Pac, What Love by Jagwar Ma, Multilateral Nuclear Disarmament by the Beastie Boys, Inside Out by Anthrax, Show Me How to Live by Audioslave, Double Trouble by the Roots featuring Mos Def.
1) iPhone 5 source: Best sounding cans I've listened to on this source. They give good frequency response but you can hear the source struggling at the highest and lowest ends, and lacking a bit of separation in the middle. It would be a crying shame to listen to these cans using only this source!
2) MBP Retina with iTunes: Similar to iPhone 5 but with more power, sound fills the cans much better, fills out the bass and treble a bit more, but still no where close to the potential.
3) MBP Retina with Audirvana: Now we're starting to see some real audiophile grade excellence, much better definition at high and low end, still not fully separated in the middle, but already very musical and starting to just enjoy the music without analyzing the sound so much.
4) MBP Retina USB digital out to Fostex HP-A3: Wow! This is a dream! The bass has such a deep tight punch! I've never heard cans this size that deliver such fast powerful bass that is so deep in extension. I absolutely love it! The highs are polished, cymbals shine without sibilance, the separation across the spectrum is fantastic, the mids and vocals are not as forward but blend nicely with everything else going on.
5) Marantz M-CR603 CD direct source: Super clean, and quite nice across the spectrum, but lacking the same deep bass punch as with #4 above. The Marantz seems to roll off at low frequencies, and is anyways built for loudspeakers+subwoofer (a pair of Dali Zensor 1s sound wonderful, but don't have the deep bass extension).
I think I will be looking to modify the pads as suggested above, I feel like these can achieve even better soundstage. Also, I have a very big head, and these don't even fit over the top of my head, I have to have them scooted toward the back of my head…still very comfortable, but I can sense the potential improvements. With the stock pads there is really good sound isolation, I wonder how much I will sacrifice by modifying the pads?
The only downside is the cord(s), which seems to be somewhat flimsy for cans that certainly deserve much better. I'll be reading once again through this thread for any information on improving this aspect.
Wow, I still haven't spent more on a pair of headphones than I paid for my Fostex HP-A3 ($280 equivalent), but the ES10 especially sound simply miraculous when paired with this higher-end DAC/mid-level amp. I hope others who own the ES10 have the chance to listen to them downstream of the HP-A3 (or of course even better, the HP-A8)…together they sound vastly more expensive and rich, I can't say enough for this pairing! The HP-A3 tightens up the bass and trims any flab that exists on other sources to zero…you simply get ultra-nice bass punch, and 32 bit high-level DAC polishing across the higher end of the spectrum (you won't need to worry about it).