My friend came by with his Violectric V200 and Woo Audio WA7 today. They sounded basically the same to me. My friend is a professional sound engineer and he claims to hear differences in micro detail, but I couldnt detect the subtle differences he described.
He also brought his Beyer T90 and HD600 - both sounded bloated on my Carver - the T90 was absolutely awful - so muddy and bloated!
All the headphones sounded great on the V200
For grins, we moved the V200 down to my home theater and compared it to the headphone output of my Pioneer Elite Class D AVR. Damned if I could tell any difference between them. Again, my friend pointed out some microscopic differences he could detect (the decay of a banjo pluck being minutely tighter defined on the V200 and more blurred on my Pioneer) but i couldnt hear it.
I am reminded that most of the talk about amps and DACs here is pure hyperbole. I'm not saying differences don't exist, only that they are very subtle (or undetectable) to a casual listener. I've been an audiophile for 40 years but I definitely don't squint my eyes and play a 10 sec piece of banjo solo for 15 minutes to critique the amount of ringing I detect...LOL. After listening to the V200 (which is arguably a reference level headamp) back-to-back with my Jack of all Trades home theater receiver (with an unknown spec built-in headphone jack) I am more convinced than ever that I dont need an expensive head amp to make the HD800 sound good.
And I have fallen in love with the HD800 - it is an incredible headphone that reproduces music like no other I have ever heard. It's balanced, musical, true to the source, fun, and open/airy all at once. No frequencies or colors jump out or draw attention - it's just an organic, natural sounding headphone. So now im thinking i will either find a good quality SS headamp and DAC to place next to my Carver, or move my Carver to my office system and replace it with a modern integrated amp with a good sounding built-in headphone output.