Amp — Leave on or turn off

Tube stuff gets shut down when I'm not near the room or ready to go back; some solid state stuff needs to be plugged in for a long while before it comes on song. 

I used to have a Lamm L2- two chassis line stage with a solid state audio path and tube rectification. Vlad said to keep it on all the time, which I mostly did (in NY) except during fierce electrical storms. It took days to come back on song from a cold start.

There's a piece by Sear of Sear Sound about shutting off recherché gear. You should be able to find it on the open web. 

@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.