Tvad, when I compare these two amps, input inpedance had nothing to do with it.
My main SS preamp is an H20 Fire, which has no problem driving the Pass.
My other SS preamp is a Parasound JC-2. I've used many other preamps with the Pass as well, including the Pass XP-20.
When I say 'rolled-off', I mean in comparison to other amps, i.e. the Pass is slightly darker sounding than my Bat, or other amps that I've owned (Theta Citadel 1.5 comes to mind). This is with solid state preamps, NOT tubes.
Yes, I tried a couple tube amps that were not good matches with the Pass (Ref 3, Audio Valve Eklipse), but that hardly means EVERY preamplifier I've tried has been a mismatch.
No amp does everything well. Pass amps are biased towards great midrange and in my humble opinion, aren't the last word in bass control.
