BTW I linked those bass port mod measurements on the first post.
I haven't been visiting that much lately.
I also have often found the Q701 at times lacking warmth with really specific setups.
When using the docked Ipod Touch 2G to O2 it seems to be the thinnest/brightest it's ever been. I really don't like this combo at all.
I think the problem is that the Ipod Touch 2G has some harshness in there somewhere. Both of those together make the Q701 sounds much thinner and tinny sounding.
I'm not a huge fan of the O2 with the Q701. It's OK, but I prefer the technically worse Fiio E9 (just for the Q701). When I use the O2 with the Q701 I have to use a source that has extra warmth.
In my bedroom I currently am using a docked monochrome Ipod Classic 3G that uses Firewire! Sounds pretty good and has a Wolfson DAC. Somehow the bass of the Q701 seems a bit "off" with the O2.
The Vali sounded great with the Q701, but not with much else. The Vali and my Micro Amp + Astrodyne PS sounds pretty similar with the Q701.
FYI the iFI iCAN, Micro Amp and Vali also are pretty close in sound with the Q701. The iFI iCAN was the warmest but had the smallest soundstage. The Micro is like a much smoother O2 and sounds perhaps a tiny bit warmer than the O2. It's not a warm sounding amp though at all. I would say it's just not cold/analytical. Perhaps like an O2 tuned by ear with dozens of headphones.
Lately i've been trying the Q701 with a Bravo V2 ($60 hybrid tube amp) and really don't like it. It's kind of harsh with any source. It has tons of volume but seems to just not sound great with the Q701. It does however sound amazing with my HD-650. My guess is that the Bravo V2 is just not a good match for the Q701.
Sometimes I wish I had two Micro Amps because the Q701 always sounds amazing with that.
I swear that someday i'll do a head to head deathmatch of the Micro vs the Matrix M-Stage. I only picked the Micro due to being US built. Been loving it with the AKG headphones since I got it probably 3 years ago.