Quad Mono topology: Four mono Class-A single ended amplifiers, two on each channel working in opposed phase to get a full balanced output, or bridged for the single ended output in unbalanced operation
Cons - A bit expensive and the paint was coming of the faceplates on the top
This thing was good although I don't think I'll be using it much because of my B.H.S.E. The 2 volume knobs are an extra as well because what is someone's slightly deaf in one ear. It's fun to play with anyway. Oh yeah and there are these little screens inside of it to adjust the tube bias or something I think it's for. Maybe how much life is left in them or something. I never actually played with the screens or the buttons anyway.
PS: Why I paid so much for mine is because when I bought it the Aussie dollar had a really low value.