Amp — Leave on or turn off

@soix "..but I know some other manufacturers recommend turning it off so may be product specific (obviously you don’t wanna leave a Class A or tube amp on). Anyway, I’m with you on just leaving it on."

My primary all-tube system with tube preamplifier and mono tube amps have easily accessible on/off power switches. Warms for 45m prior to use, does ok.

Now the secondary system I’m working on now, solid state Class A amp has a power switch on front, and yet the matching Class A preamp has no power switch at all. Plug in the preamp, and it’s left powered on all of the time, as designed.

I can honestly say both systems do sound better, or at their best, when all of the components are good and warm, big iron transformers extra warm and saturated at 4+ hours. What was odd and memorable was rechecking after being left on for 24hrs, could usually hear something a little extra special or more engaging each time. Same occurred with many of my former Class A/AB dual mono solid state amps.  Reaching that optimum sustained operating temperature perhaps. I try not to leave any of them on though for more than 4 days max, if I know I’m not gonna use it for a week or more fwtw.

This what others have already said, component dependent.  Our tubes amps change in about 20-30 minutes and can max out in 2 hours or less.

Happy Listening.

I tend to lean towards leaving things on, and digital/transistor for sure.

I think what the manufacturer recommends is irrelevant.  What matters  is your own ears, and your willingness to pay the electric bills. :D

If you can't hear a difference, leave your gear off.  If you can, leave it on.  It's that simple.  No measurement is going to tell you any better.

RV, I have repeated your experiment a number of times with the same results. On longer always sounds better, but with diminishing returns, for about a week.

Its’s true of my DIY phono/pre - it’s on all the time. It’s true of my DIY Class A amps (they idle continuously at half power). It’s true of my Bryston SST in the HT (although B recommends turning it off). But since HT doesn’t matter nearly so much, I do turn the B off, and then back on an hour before - but an hour isn’t really enough.

My cartridges take 10-40 minutes too.

As for the car analogy, I ALWAYS used to warm up my engine carefully, and my tires too, before taking a fast lap.

YMMV