I leave ss components on 24/7 (in low power "sleep" mode if available). Tubes I fire up at least 30 minutes before I start listening. I do think things sound better after listening an hour or so. Theo's observation about cartridge performance is interesting. I'll have to try and see if I hear a consistent improvement listening to the 2nd side of the first LP played in a given evening.
does your system "warm up" and then sound better?
I leave my amp on all the time but I'm wondering if all the other components warm up too. Speakers, pre amp, cd player, cables, ears? It seems that my system sounds better after an hour or so. What gives?