How Long To Warm The Tubes???

Canadian Charlie

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For those who own tube/ valve amps this question is for you.

How long do you all wait to turn on your amps after you turn on the pre amp tubes???

If I let it warm up for half an hour or more I get a nice sound, if I only give in 10 minutes I get a bad tone
 

grumphh

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Switch it on. After 15 seconds or so it should make sound. That is when i start playing.

For the first two minutes or so the sound is different than it is after those two minutes have passed. Different, not "worse" or "better".
 

CB91710

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Ya, the tubes are up to operating temperature and conducting within a couple of minutes.
If the tone is changing after 5 minutes (good or bad) I'd suspect a component is going bad and the heat is effecting a change in value... capacitor, resistor... could even be high bias causing the tube to get hot.
 

PierM

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15/20 seconds. Something wrong is happening there, not a normal behaviour.
 

StudioFan

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I guess it depends on how long you want to cook your tubes.

I have blown an el84 due to short warmup and cranking wide open into an attenuator....an extreme case .

Now I let them warm up for 5 minutes or so and I wait a little while to really give them the business (6-10 vol .)
 

ErictheRed

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Tubes will warm up in about 30 seconds. There are other factors, too: your strings are stretching out, the speaker is moving and potentially shaking some dust off, etc. In those thirty minutes, you will probably have adjusted the tone stack or volume on your amp, as well as your guitar, even if only slightly. You will have stretched and tuned your strings once or twice.

The biggest factor might be you, though. You are warming up, your hands are warming up, your ears are warming up; you know what sounds like good tone? Bending to the right pitch! Using good vibrato! Not to mention that the beer you had or the bowl you smoked is starting to kick in, etc. Everything else is just your imagination.

I hate to play this card, but I'm an electrical engineer and know what I'm talking about. The tubes warm up very quickly, but there are the other factors that I listed, and probably more.
 
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northernguitarguy

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On most older tube equipment, the warm up period wasn’t on standby. Once they were warm, the devices would start working. No ‘cool down’ time, either. It just got shut down.

Lotsa myths about tube fragility.
 

ehb

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Fairly quick warmup (heater||K)....

Voltage operated device, bias, stable ICDQ/ECDQ, etc......

If it is changing radically, I would think something else besides jugs....


Summin be pushing on dat Q dot on the swirly lines... ;)
 

Eigen

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I don't know, definitely feels like my mark iii sounds better after its been played for a while, always assumed it had more to do with all that iron warming up though.

The tubes are at operating temperature more or less when they start producing sound, like they do on the older non-stand by amps, like Champs.

If there is a significant change in tone after 15m, it could be a cap related issue as already pointed out.
 

Standard 64

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I would agree tube amps do sound better after half an hour.
 

sonar

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Tubes will warm up in about 30 seconds. There are other factors, too: your strings are stretching out, the speaker is moving and potentially shaking some dust off, etc. In those thirty minutes, you will probably have adjusted the tone stack or volume on your amp, as well as your guitar, even if only slightly. You will have stretched and tuned your strings once or twice.

The biggest factor might be you, though. You are warming up, your hands are warming up, your ears are warming up; you know what sounds like good tone? Bending to the right pitch! Using good vibrato! Not to mention that the beer you had or the bowl you smoked is starting to kick in, etc. Everything else is just your imagination.

I hate to play this card, but I'm an electrical engineer and know what I'm talking about. The tubes warm up very quickly, but there are the other factors that I listed, and probably more.

This.

Don't underestimate the perceived effect of your ears acclimating to surroundings.
 

M.C.J.

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Usually it's about 2-3 minutes in standby after which it comes out of standby and ready to play. There are times when I leave it in stand by a little longer because I'm doing other things and 2-3 minutes becomes 5-10 minutes. I don't hear much difference in tone because it's gonna get me that tone either way.
 

Thunder Dump

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The key is just avoiding quick significant changes in temperature--internal or external.

Like others have said, from an electromechanical standpoint, the tubes will be warm enough to accommodate the higher voltage after about 30 seconds. Just remember that in the winter in places where it gets really cold, if your amp has been sitting out in the car before a gig you should ideally let the entire amp warm to room temperature while off before turning it on standby. Similarly, if you run an amp hard/dimed out for an extended period of time, it's good to either return it to standby for a minute or just have it off for a minute before moving it. At full tilt the filaments will soften and you risk distorting or damaging them. Again, less than a minute of cool down before moving is fine. Tubes will still be too hot to touch, but no physical damage (although don't bring it out to that freezing cold car right away).
 

ehb

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Before Gunsmoke came on after school, I would turn on the RCA Victor, go make a sammich, pour a glass of tea, sit down, and be part way through the sammich by the time the TV was warmed up and full on....
Fun to turn it off at night and turn the lights off to watch the coating glow die off....
When you ain't got much, it don't take much to entertain you...


Bud down the skreet had a COLOR by gawd TV! I'd go to his house to watch Wild WIld West...in color, bitches...


Damn, high technology was amazing back then....

Now you can snag a flat from hell at Wally World that'll cover half a garage door for three or four C notes...
 




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