Pros: Speed, clarity, incision, impact, separation, dimension.
Cons: Very slight emphasis on upper frequencies.
I was listening to music through the Peak yesterday. And it was such a thrilling listening session. However, I did something unusual: I stopped.
I hit the pause button after a particularly great song, and took off the headphones. I held my breath for a moment, and closed my eyes. I wanted to remember this moment. Just in case it never sounded this good again.
"That was it," I said to myself. The place I've been trying to find for a few years now.
Then, as I recalled the long and expensive journey that got me here, I became a little upset with myself.
I was upset with all the money I had spent on "audiophile headphone amps" which, as it turns out, left so much to be desired. Then I thought to myself: Without that journey, would I be able to appreciate just how good this amp truly is? Probably not, I concluded. But I suppose I'll never know for sure.
So, I came back to the Peak today, and began listening. And, you know what? The magic is still there.
The music is immediate, alluring, and crystyal clear. It is exceptionally well defined, but never analytical. I can follow each instrument, and locate it spacially. From the moment of attack, all the way through its decay. Transients are incredible, but the music never becomes shouty. In fact, the control through busier passages is something of a revelation to me.
I will admit that I hear something of an emphasis on the upper frequencies, as others have. But I will go one further in saying that my ears have been listening to tube amps for a while now, and I'm fairly certain that there's simply more high frequency information here than I'm accustomed to.
In summation: This amp is fantastic. That's just all there is to it.
Update - May 2012:
I just purchased my second Peak/Volcano, giving me matching (sort of) work and home rigs.
And I am pleased to report that the standby and power lights on the Peak/Volcano now are matching yellow, in lieu of the green standby LED used in the first batch. A subtle change, sure, but one that makes the Peak/Volcano a touch better looking when switched off.