Not all amps and speakers, but I have gotten great advice and help from the following:
BAT Audio - Victor Khomenko (amp)
Sutherland Engineering - Ron Sutherland (phono)
GEM Dandy Products - George Merrill (turntable design/builder)
BAT Audio - Victor Khomenko (amp)
Sutherland Engineering - Ron Sutherland (phono)
GEM Dandy Products - George Merrill (turntable design/builder)