How long does it take your tube amp to warm up?

If you are talking warm up vs. how long it takes to sound its best, I think these can be two very different things. My tube amps are ready to play, so they are warmed up, in about 15 minutes. However, to sound their best, about an hour or so of playing time.

In my main system, 45 minutes to warm up a pair of Lamm ML2s with a fresh tube complement. I usually do that with a digital source. It takes about 3 sides to warm up the tube phono stage and cartridge. I can make the time coincide, but that's the reality.

A different tube system, running a restored pair of Quad '57s and Quad II amps using GEC KT 66s (real ones) takes at least 20 minutes to come on song, more time is better. The speakers are on constant charge. 

It takes longer for SS amps to reach optimum performance, especially Class A designs. Most tube amps will sound as good as they ever will after an hour.  SS amps benefit from never being turned off.

It takes 3.5 minutes…. The time it takes for the soft startup to complete and the amp to switch on. 
 

I used to experience a long warmup for my Audio Research REF 5SE preamp… it took about 12 minutes with signal running through it, and the improvement was substantial. But with the REF 6, that has gone away… sounds great as soon as the 1.5 minutes of soft startup is over and the mute comes off.

I have a pair of Cary 211FE amps which take an hour to an hour and a half to reach  what I call the Golden Zone. If right from the start I push them hard an hour but if I have company I like to slowly build up the volume so it will be about an hour and a half.