My tube amps produce front to back depth that any solid state amp that I have owned could not match!
Very interesting post ..... Thanks....
The most back to front depth possible experience may include the listener itself and create some effect like in headphone... It is my experience WITH a solid state amplifier, then acoustical control indeed play a great role...
My Sansui is a good amplifier BUT not the best in the world then acoustic explain my experience...
And tube amplifier resist more to bad acoustical environment than most S.S.
if someone think that i am wrong i will listen to him...I am absolutely not a specialist.... this question thread is interesting .... thanks to the O.P.
My best to all...