It was only single ended. Not a balanced beta22.
It sounded pretty good, but we needed to max the volume out even with the zapfiltered opus.
Steve's balanced beta22 was not done. I think that balanced it would have been ok. I'm pretty sure Steve's is going to be balanced with a gain of 11, so you might want to PM him and/or Fierce_Freak if you think that is a bad idea.
We could only hear them balanced on my amp, and it was not a good match. The Orthodynamic drivers in those headphones have an impedance of 120ohms, but must be extremely sensitive or something. There has been some speculation as to whether or not they present a capacitive load. Anyways, they don't exactly sound right on my amp.
Sorry if I wasn't clear.