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

60 to 90.......................seconds.

5 minutes at most. 7 tubes in mine.

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.