Jerry
not sure how large (power output) a Pass amp you are contemplating...but here is my very recent experience.
purchased a used Pass INT-30A (integrated) to get my first ever taste of class A power without investing to much cash. The Pass integrated (once warmed up) provided much more detail better midrange plus a wider soundstage with both my Elipsa's and Tannoy's (vs) my previous McIntosh C50/C2300 to MC 1.2kw's to Elipsa's or Tannoy's set-up. The Pass integrated is impressive (class A power is remarkable) made both my Elipsa's and Tannoy's come alive, however, the low-end provided by the Pass integrated was somewhat lacking (not surprisingly), as this confirmed exactly what I read about the Pass integrated, since it only outputs 30/60watts class A.
Then tried the INT-30A preamp outs into my McIntosh MC 1.2kw's and
"WOW"
now that's the sound I've been chasing for quite some time, really happy with what I was hearing, the MC 1.2kw's provided better low-end without compromising the new found details, midrange and bigger soundstage provided by the preamp section of the Pass integrated. I now listen to my system much more with the Pass + McIntosh combination vs my full McIntosh set-up.
I'm now thinking how do I get more of that beautiful sound (sounds familiar ?) The preamp section of the INT-30A is = to the Pass XP-10, so I plan to trade the Pass INT-30A towards a Pass Labs XP-20 to feed my McIntosh 1.2kw's. Based on what I have read here and elsewhere regarding the Pass XP-20 that unit should give me the "little bit more" I'm in search of.
I did also think about getting a more powerful Pass class A amp, but along with those come the additional heat/power consumption, that I do not want -- ya gotta love those cool-running MC 1.2kw's (right Jerry
)
BTW........the Pass INT-30A (discontinued and replaced by the INT-60) is a great unit I could easily live with - and the heat output is minimal.
Interesting thing is I originally purchased the Pass INT-30A with the hopes of downsizing my system to a one box solution - oh well, I guess I'm still in the game.
Hope this helps.