Leaving tube amps on.

I would leave them on, assuming that I’m in close proximity to the amps and able to react quickly if a tube event occurred.

 I had an ARC amp that took 45 minutes to warm up and for the sound to bloom and I’ve had that experience with several of the amps I’ve owned. If you’re having short listening sessions, and that’s just the norm and unavoidable, you should be listening to your system delivering peak performance and not hearing the sound of an amp going through a warmup cycle. Your only offset (aside from safety) is that you’re going to be replacing tubes at a higher rate hence you need to decide whether you can justify the extra cost, or not. If not, buy some good solid state amps.

That would be my approach but I can also understand why some might disagree with it.

That is a great question. I got interested enough to read the manual and give it some thought.

My conclusion was simple. Call Audio Research and discuss with the technical representative (I forgot his name).

The new generation of ARC amps have slow startup and there is very very little improvement with warm up. You will have to assess yourself how much fidelity improvement there is as this is a bit older design. Also, that is a massive power amp… with 18 KT 150’s being run hard. So the recommended replacement time is 2,000 hours for those tubes. The small ones 4,000 hours. For me, balancing the above aspects I would turn it off if you were leaving it more than 15 - 30 minutes.

One thing I believe true however is that tube life is longer if left in idle mode with no music going through it… but then you will not be using the hours meter to change tubes at regular intervals, making maintenance more difficult. With ARC, I do what they say as far as tubes.

better safe than sorry. when tube goes bad anything can happen including anything that had been already happening.

leave tube amp on, you are at the fire hazard.

I would leave them on, assuming that I’m in close proximity to the amps and able to react quickly if a tube event occurred.

leave tube amp on, you are at the fire hazard.

I love the idea of leaving them on, but I cannot park myself near my amps all day long, and a fire is a terrible thing. This seems like an easy one.