For what it's worth, I prefer the HE-6 better from the BA (or any other quality amp) than any "speaker" or "high powered specially made for ortho" amp I've heard. This is provided I roll tubes that work well with the HE-6. I had no problems with gain or power, but the HE-6 is not one of those headphones which I like to blast loudly like the SR-007 or LCD2 to a lesser extent.
My opinion is of the minority though. For me, powering the HE-6 was always a matter of quality vs. quantity, provided that one had sufficient quantity. I'm not saying speaker amps such as vintage receivers, etc. don't work well with the HE-6. They actually do. A lot of speaker amps and receivers (with more caps in signal path, gain stages, etc.) tend to sound darker, thicker, slightly veiled, and slower compared to most head-amps. These qualities oftentimes result in a good match with the HE-6, which can sound etched or lean with many head-amps.
Edited by purrin - 9/5/12 at 1:03pm