Interesting topic, though I am no electrical engineer....but....just so happens I received my ‘new’ mid-80’s Belles 400A amp this past weekend. All 60+ lb of it; two large torroidal transformers, eight huge Mallory caps, and a total of 24 Motorola MJ15023 transistors. Damn thing is a beast.
Anyway, removed my old B&K, hooked up the Belles, turned it on, and although somewhat impressed immediately, it wasn’t until an hour or two of listening that I said to myself, ‘damn this amp is getting better as I listen and it gets warmed up’. The soundstage seemed to be getting deeper, wider, more ‘lush’, and better overall imaging. After a time, I became more and more impressed. I hadn’t even thought about the fact that this should be happening or not with a solid state amp, but it sure seemed to be the case. At least that’s what my ears were telling me, or, was it just myself getting more immersed with this new ‘beast’? Dunno, but I did consciously think about it warming up = sounding better.
Since, I have turned it on at least an hour before I begin listening. I never thought about doing that with the my old B&K.