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When to power off a tube amp?

So I just got new tubes for my Lyr and really don't want to damage these tubes and want them to last for as long as possible. So I had a few questions and was hoping you guys could help me, thanks.

1) Should I turn off the amp if I am going to away for like an hour or so? Would that decrease the life of my tubes more than leaving it on that whole time I am not using them?

2) Should I let my tubes warm up before using them? If so, how long should I wait?

3) Is unplugging my headphones before turning off my amp necessary?

And just a random question out of curiosity, what if you use two different tubes in a tube amp? lol.

Thank you guys, any help would be much appreciated.
highrolller
swampwalker's avatar
swampwalker
5,138 posts
 
1. General consensus is that for safety purposes, it's not a good idea to leave a tube amp unattended for any significant period of time. In my case, that means if I leave the house, I turn it off.
2. Let 'em warm up if you want, but no reason not to listen if you want to. It can't hurt the tbes.
3. If the amp is has tube output tubes, it's not a good idea to run them w/o a load, i.e., headphones.
bjesien
1,239 posts
 
I've never heard a good reason to leave them on after listening as they warm up within five to ten minutes. I've never had an explosion but there is enough plastic volume in the boards to get a good roaster that could catch a pair of drapes on fire. I'd say even though you can burn down the whole neighborhood on occasion, tubes are worth it.
tomcy6's avatar
tomcy6
2,539 posts
 
Many recent vintage tube preamps have a slow start cycle built in. It slowly increases the voltage going to the tubes over a 20 to 45 second interval when you turn the preamp on.

Preamps that I know of with this feature include PrimaLuna, c-j and Aesthetix. If your preamp has this feature, I think you should turn it off if you won't be using it for an hour or so. The life of small signal tubes is being used up even when music is not being played through them, although at a slower rate than when music is being played through them.

I am not a tube or electronics expert, so if i am wrong about this, please correct me.
georgehifi's avatar
georgehifi
10,312 posts
 
Tomcy6:
"Many recent vintage tube preamps have a slow start cycle built in. It slowly increases the voltage going to the tubes over a 20 to 45 second interval when you turn the preamp on."

I think you'll find that's because they used tube recifiers, not solid state ones they use today.

Cheers George
highrolller OP
6 posts
 
Thanks for the input guys, greatly appreciate it. I am getting mixed responses as to if I should turn it off when unattended, etc so I will just await more answers I guess.

My Lyr has a 20 second mute relay switch, does that mean it cannot explode or arch when I turn it on cold? Thanks guys.
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