So I finally tried the amp with my AD2K last night before packing it up to send back to Romanee:Bass
Now *this* is holy bass, if there ever was one. Much has been written about the AD2K's bass in the review I wrote that's in the Featured Full Reviews for Headphones, and the V2^2 only made it more low-hitting. If there's one word that sums it up, it'd be: thunderous. Not so much on the wham/slam side of things (as the AD2K doesn't have that kind of bass), but more on the forceful, low-hitting almost-up-from-below side. If there's a combo that can give an accurate portrayal of rolling thunder or earthquakes for example, then this is it. BAM! Treble
As I expected, the V2^2 sharpened up the otherwise relatively flat treble of the AD2K, honing it with more precision and bite. With the V2^2, the AD2K was simply able to capture more guitar-string detail for example, like a loose string, or a fast twang, etc. It didn't make the AD2K any brighter though, just more on the ball in terms of precision and conciseness over extremely fast sounds. A definite improvement over the AE-1, but in comparison to the GS-1, about the same (but the GS-1 taking the lead in terms of giving that extra layer of air and space around notes).Soundstage
This wasn't quite an area where I really felt the V2^2 was close to the GS-1. The GS-1 gave a more intangible natural feel, as if you can feel like you're carving out the air yourself and look where you want to without being forced to look where the amp dictates you can. The amp seemed to take away some of the natural soundstage of the AD2K, kinda channeling it into the way it wanted to, instead of letting the headphones do their own thing.
The effect was pretty noticeable on music with highly directional positioning, as I got more of an impression that it was forcing the illusion of an oncoming wall of sound, whereas the GS-1 let sounds drift/float from one channel to the other as they got closer to the listener position, as was probably intended.Conclusion
So the V2^2 Maxxed turned out to be a good match for the AD2K, but not a great one. The amp has more than enough ability to drive it of course, but I didn't find it entirely synergistic. Yeah, some people will want to sharpen up its treble and let its bass get empowered, I'm just not one of them.