I am an owner of the HE-6 currently.
It's a second pair [the driver died in the first unit but the replacement process was flawless so no complains + kudos to you guys ]
The headphone is awesome, I will merely post suggestions to what could possibly be improved with the new HP [might have been posted before]
Headband - could use a bit more padding [extending the HP a bit reduces the pressure in my case],the leather feels really nice though.
Supporting yokes - no complaints, only the yokes/headband could be a bit more symmetrical [not because of the looks, but it slightly impacts comfort]
it is not that bad, but it can't be completely remedied
Plastic [L,R, logo] adjusters - no problems here but according to others is the breaking point/structural weakness, so should be metallic perhaps
this point, I guess
Cups - no complaints, could be probably metallic, really like the matte finish
Pads - love the deep grayish velours [I believe they are discontinued now, but please offer a deeper variant than the current one ], leather could use improvement according to others
thicker x thinner velour pads
Connectors - XLR is the way to go probably, those SMA connectors are not ideal, generally speaking [troublesome installation, weak stress relief,...]
Cable - fine with me, OCC [or OFC] is nice, some issues with [OCC] cable oxidation according to some users though. The HE-5 [silver] cable was probably even better back then [it is the one I am currently using and love it], best would be probably silver coated copper if it wasn't too expensive but I don't really care about cable as long as it is relatively flexible and well made/sleeved.
Package - Nice in my opinion, could use a plastic box I guess :D
Those are just minor nitpicks, the SQ is awesome [almost flawless, save for a minor 7-8khz occasional emphasis], so only the build quality could use a little overhaul :]
[You could read my favorable review here - http://www.head-fi.org/t/650912/hifiman-he-6-ultimate-review-write-up-3-2-13-updated-comfort-pads-and-sound-lows-mids-vocals-expanded ]
RE-400 is awesome as well. Really love it [only nitpick is the cable, the right driver is starting to drop-out occasionally, so the internal cable wiring I guess, but it happens only rarely ] but I really love it. SQ for an IEM [+ just a 100 bucks] is simply superb.
I really wanted to thank you for offering TOTL products with superb SQ, for a rather reasonable price.
So this is not a complaint, merely suggestions. I am happy as could be right now :]
Here is hoping for even bigger things to come in the future :] Just HiFiMAN from now on for me :]
Cheers to you guys
Looking forward to your next HP [RE-600, rumored Jade II, HE-600/7,...]
Edited by conquerator2 - 5/2/13 at 1:46pm