I’ve never heard this amp, but have sat in on a few discussions of it. I am under the impression that Bob did all the design work. The amplifier does seem to be unstable as it sits, but several mods have been done to change the wiring and grounding scheme. I believe that there are many AC and DC cables bundled together as well as grounding all over the amplifier rather than using a common grounding point which causes this amplifier to be quite noisy. Also a lot of talk about poor capacitors used, so any amp not updated would need some work.
Good luck, Tim
Good luck, Tim