Quote Originally Posted by Ian Mackenzie View Post
Warmth equates to the 2nd harmonic distortion in the context of THD.

Class A power amps have inherently low 3rd harmonic distortion. SE class A amps exhibit tendency towards warm sound in the absence of 3rd harmonic distortion.

SS SE amps like the Pass Aleph where like that. They are very nice but not on trend in terms of contemporary hifi listening.

In contrast the Pass X series cancelled out the 2nd harmonic distortion.

Pass then added a small amount of SE bias up to a few watts in the X.5 series.
I have one of those the X250.5.

I don’t mind tubes in preamps. They can add. A certain emotional feeling. Again it’s the 2nd harmonic distortion.

A bit of 2nd harmonic goes a long way with metal diaphragms.
That is why I detest most solid state guitar amplifiers, other than the better modelling ones. Don't get me wrong, theres some tube instrument amps sound terrible as well...my old 100w Garnet Deputy 2 combo amp comes to mind...but I'll take my pre-CBS Fender Bassman blackface head over most anything solid state for playing guitar thru.