Wavelength Proton

I used this once with the senns hd650 and the performance is ok. Despite it has negative reviews...

I can't comment on the Proton as I've never heard it in my system but agree with the posters above about Gordon.

I own a Crimson.

I just got a proton recently, and love it! I haven't used it with headphones yet but I love it hooked up to my main system. Ditto on what Docmark said about Gordon, great guy!

I just purchased the Proton. I'm using it with a MacBook Pro running Amarra. It sounds great. I use it as a portable DAC with headphones - out for coffee, that sort of thing. I'm having a blast downloading hi-res files. As well, I found that J. Gordon Rankin (head guy at Wavelength) is incredibly helpful if you have any concerns about the Proton.