A lot, maybe most tube amps, at least those along the lines of marshal with NFB sound very different at low volumes than stage volume. In particular, feel more than sound even. Highs become harder and more present and the feel becomes stiffer. Harmonic content tends to give way to more fundamental. At low volumes they will Feel smooth, have a sag to the feel and sound rich with a good balance of all frequencies. Some more than other. What amps of the master volume type that get a large potion or most of thier OD from the pre have you owned or played that don't have this issue to the degree most do? And yes, i do realize it's partially the speaker, the human ear, etc. I just want to know what amps you've experienced that do it the least. Not looking to buy an amp, i just want to study the schematics of amps like this and see if i can determine what it may be that alleviates the issue, if you wanna call it that.