I've used tube amps on my Model III's as well as solid state. The tube amps were magical. Solid state was amazing but tubes on those babies...whoa!
In fact, I found my Audio Research VT100mkII w/ ARC Ref-1 pre was better than my Acoustat Monitor IV's with their servo tube amps and the same Ref-1 pre.
In fact, I found my Audio Research VT100mkII w/ ARC Ref-1 pre was better than my Acoustat Monitor IV's with their servo tube amps and the same Ref-1 pre.