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

My tube amplifier has about 12 tubes and takes a couple hours for it to open up and sound really good and comfortable to listen to. Always wondered why it takes so long for a tube amplifier to warm up and what’s happening during this phase.

If I left it on for six or seven hours would it sound even better? I normally don’t leave it on for more than four or five hours.

How long does it take your amplifiers 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.


what might be a better ? to ask is do those big exotic caps and or cables ever form with the relatively tiny signal… ? see DBS patent… and ponder that the application of it might not be limited to just cables…..

When I had my Viva, it was 45 minutes. Now I’m putting together an Audio Note system and I find it’s about 2 hours.  Peter Qvortrup leaves his tubes all the time I think. But that’s not a good idea for most people. 

Turntable grease bearing takes 20 minutes to "warm up." By the time that’s done, all tube amps (RIAA/preamp/monoblocs) are ready to go. While things are technically available after 2 minutes, sound opens up and has more musical coherence after 20 minutes, and gets better by the hour. After 3-4 hours, system sounds best.

About 45-60 minutes for VAC Avatar SE, but you can listen to it after 10-15 minutes.

I don’t have any reliable way to determine how long it takes for the system’ to sound its best.  It sounds good enough to enjoy within 20 seconds or so, and pretty much like it always sounds within s couple of minutes.

From my experience, it doesn't matter how long you let the tubes warm up. The amp won't sound its best until after 15 minutes of signal has passed through it. Ten minutes of idle is all it takes for a KT150 (the highest power dissipating tube out there) to reach operating temps, so I assume all other tubes require less. You're just killing tubes by letting them idle for hours before playing.

30 minutes...and 30 minutes to warm up and expand the voice coils in your speakers...... after 30 minutes of Playing, you should have the optimum sound that your system will produce.

By the time I have my first drink, my amp and I are both warmed sufficiently.

It sounds good after a few minutes. But most tube amps do. About 45 minutes to an hour and it sounds optimum.

My amps are SETs and a very simple low parts circuit and sound good right out of the box. It's possible they start to sound better after 30 mins or so but wouldn't want to bet my life on it.

My Audio Note Cobra takes 30 minutes...can't listen to it before then. After 30 minutes, it is an entirely different listening experience.

I have the Audio Research Ref 750s with 32 KT150s. 36 tubes all together. And I let my amps warm up for 15 min.Same with my Audio Research Ref 6SE Pre. 

It is not only the tubes but also the transformers that need the warm-up. My Aric Audio pre and amp come to life regarding soundstage and 'air' after about 45 minutes. 

I believe speakers also need a little warm-up time.

     When a system is first energized; everything from the source to the speakers is, "warming up" and will perform best after a couple discs are enjoyed.




Even solid state machines will sound better after they are fully warm up. I always keep my SS preamp and clock (for the source equipments) up all the time.

Please let's not keep the equipment on all the time. There is a need to be somewhat concerned about environmental issues.


Please let's not keep the equipment on all the time. There is a need to be somewhat concerned about environmental issues.

Oh brother....🙄

I used to complain about my Primaluna's needing 2 hours to warm up and really sound glorious. However, I now realize that neither the amps nor the Sophia Electric blue "coke bottle" EL-34's were actually broken in. The Sophia's have a 5,000 hour rated life, so breaking them in takes a long time, and I listen to only 2 or 3 CD's per night. The break-in is loooong. Now that everything is settled, the amps are good to go right out of the gates after 15 minutes. They still gain a more awesome midrange after an hour of playing though.

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

Forty days and forty nights! lol


Is the benefit from an extended warm-up more so due to tubes warming up or the transformers?

Seems the tubes would be getting warm pretty quickly. Since the transformers are larger maybe they take longer.

My amplifier which has around 14 tubes is much better to listen to after an hour. A bit constrained during the first hour.

output transformers need more time to reach steady state than the tubes! ref150se takes about 80 minutes for me. ref5se bass is more better 
(mo better!!) after 40 minutes. Very apparent w/a sub in the system.

My VAC gear sounds decent after 5 minutes, but incrementally improves over the next 2 hours.  I warm everything up at once and play LP's that I don't totally engage me or are a new purchase at lower levels for several sides.  The other question is: once warmed up, does it take the same amount of warm up time after it's turned off and restarted to sound superb, or is there residual heat that remains.  Thinking of the scenario of going out to dinner (I never leave my gear on when I'm not home) and then once home again firing the system up again.  I would think that one would "get credit" for earlier play time.  


At least an hour for my Quicksilver Mini Mite mono blocks to reach their best sound. This is with regular use. If they sit for awhile it could be several hours for them to sound their best. 

My NYAL Futterman OTL3s, converted to triode with eight 6LF6 tubes take about 20 minutes of warming up while playing music. At 40 minutes they lock in. 

I’ve tube mono’s and a tube preamp. I’d say at least an hour to sound it’s absolute best!


To my practice, solid state amplifiers need more warming up time than tube ones. I have two of them, one push-pull with 12 tubes and the other SET with four tubes. In a few minutes they sound good, while my class D solid state amplifiers need a few hours to get closer to the best. 

Does anybody know if tube amplifiers with speakers hooked up but without any signal can stay powered on without harming them? Many years ago I got to know a very nice guy from Boston area. He was then a Thiel dealer, in particular. I was excited then with new Thiel CS 3.7s. I lost a contact with the guy, but this is what he told me. 

Tubes undergo less wear when not under load so will last longer, but I don’t think any manufacturer would recommend leaving them on: fire hazard and a really short tube life.