OK, A few quick words about my initial impressions of the Audeze 1. This is swt61, posting on Marc's CPU.
Through the balanced Beta22...
A very smooth, clear presentation, quite familiar to the Donut MkII sound (that's a really good thing IMO). Very resolving and fast, with a pretty good sound stage as orthos go.
The one real difference I notice over the Donuts is the top end. These Audeze (bare in mind these are the dBel modded units) are very hot! I didn't know that an ortho could be this hot. Now personally I like my top end just a bit softer, but I know that Marc likes his treble just short of irritating, and these are perfectly suited to his listening preference. Now don't get me wrong, I wouldn't call them harsh, and I'd most likely become accustomed to the sound quickly enough. They're just a bit brighter than what I've been using lately.
Bass is really nice. Plenty of low end info, as far as I'm concerned. Though I have not heard a stock pair, I'll say that I'm quite impressed with this version.
Through the Pass F5...
The F5 isn't what I'd call a highly colored amp, but as compared to the almost dead neutrality of the Beta22, it's subtle flavoring is noticeable. The F5 has a slightly more euphoric sound. Somewhat tube like in presentation. The top end driven by the Pass is just about perfect to my ears.
All in all a really nice headphone, and more solidly built than the pictures mislead. Can't wait to hear the 2s now!