Tube Amp Myths

Uladine

Uladine

New member
I recently purchased a Tube amp (Peavey XXX) which I'm absolutely loving, but I want to take care of it properly. I've heard a lot of different things about tube amp care, and I would like to clarify facts from myths.


First of all, I know that you should always warm up the power tubes before using the amp by putting it in standby mode for 2 minutes or so. I also put it in standby for 2 minutes before turning it off to let the tubes cool a bit. Is this necessary? I've read that it's okay to just turn it off as long as you hit the standby switch first.

Also, I know that tube amps tend to sound good when you're driving them hard. I know that if you drive a solid state amp to the point where its clipping you can damage your speakers. It seems this would be true as well with tube amps, but a friend of mine says you can crank a tube amp all you want and it wont hurt anything.


Any clarification would be appreciated.
 
Yes, you need to warm your tubes. Tubes do not work properly unless they are hot, and when you are in standby mode, the tubes heaters are working, but nothing else is. Most recording studios let their tube gear heat up for half an hour before they start using it.

And yes, distortion shortens the life span of ANY speaker. Guitar speakers are designed with this in mind. Drive that Motha!!!


Light

"Cowards can never be moral."
M.K. Gandhi
 
I have 3 tube amps. I let mine warm up for about 15 minutes before using it. It will change your sound (a bit) from the tubes being warm vs. hot.

One other thing, you should make sure that you wipe off the tubes if you touch them. The grease from you hand will put a hot spot on the tube and it will possibly crack when warmed up.
 
15 minutes? drink coffe in the meantime? LOL anywqay, according to the guy form matchless (who outta know his shit right?) warm up time is not neccessary, and if you do anything more then 30 sec. is a waist. ANd if your tone changes in the first fifteen minutes you have definately got a weird amp./...
 
I'm not an electronics engineer, but I understand that the tubes have to warm up before you use them, not just for the sound/tone but for their lifespan. That's the reason tube amps have a standby switch.

In the other hand, you can just turn the amp off as long as you go via the standby switch first.
 
pennylink said:
I'm not an electronics engineer, but I understand that the tubes have to warm up before you use them, not just for the sound/tone but for their lifespan. That's the reason tube amps have a standby switch.

In the other hand, you can just turn the amp off as long as you go via the standby switch first.
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Lol there you have the two biggest myths. Matchless amps DON"T have a standby switch... LOL and turning the power off simply turns the power off...

Grinder is right though, when tubes are warm you shoudln't move them...
 
Not only should you let your tubes warm up before using your amp... you should let your tubes cool down before moving the amp.
 
grinder said:
And wait for the tubes to cool, before moving the amp.
Click to expand...

This is probably one of the most important things you can do to prolong the life of your tubes. Also, try not to bang the amp around too much - if you tour or have "roadies" move and transport your gear, invest in a flight case for your amp head.

If you transport your tube amp in an unheated truck or vehicle during cold weather, let the amp "warm up" to room temperature (maybe half an hour or so) before you turn it on - I've cracked tubes caused by thermal shock because I turned on an amp that came right out of a truck during the winter.

If you're gigging or touring, always carry a spare set of tubes with you too. :cool:
 
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OK OK

Standy by is for, well what it sounds like....It keeps the amp powered up while turning off all the stuff that lets your guitar come out of the speakers(output xformers and such).

So----the amp is standing by, waiting for you to use it so you can take a break in between sets and not have to change your volume settings or turn the amp off, and have to wait for the tubes to warm up when you turn it back on if you have have a vintage amp with big tubes, such as a Twin.

If you have a newer amp, this isn't as much a concern or if you vintage amp has been on a while and you are turning it back on. Because the capacitors still have some charge in them. If you have a newer amp it has smallerand sometimes fewer capacitors that charge much quicker than vintage caps.

Are any of you old enough to remember TV's from the fifties and sixties? You only got a dot on the the screen untill the tubes "warmed up". The tubes warming up are just by-product of the capcitors reaching full load and discharging to the tubes which are filling up with electrons and because vacumn tube are very very ineffecient they lose energy to heat.

So technically you're not waiting for the tubes to warm up, you are waiting for them to fill up with enough electrons to reach optimum plate voltage.
 
Thanks for all the info. It doesn't look like I'm doing anything wrong, but a flight case is definitely on my "need to buy" list.
 
I have a Bassman 135 that doesnt get to the "sweet spot" until after its been on for at least 15 to 20 minutes and gets really warm.
 
Quad Reverb!

Not allowing warm up before starting to play shortens the life of the tubes. Touching the tubes create's a concentration of excess electrons in that area causing the hot spot that will lead to tube failure.
 
While it may be ideal to allow the tubes to cool before moving the amp.. It's just not realistic when you're playing a show with 7 bands and there's only 15 minutes for breadown and setup between setups.

Will this cause a ton of damage to my amp by moving it? I can't just let it sit there.
 
Only if you call cracking a bottle (tube) a ton of damage... do what you've gotta do, but if you can let them cool it would be better.
 
time restrictions are a bitch, yes. But if you are careful it wont hurt your amp. be gentle though!
 
If you are playing on a winter night and move your tube amp directly into the cold while the tubes are still hot you may cause some damage. Other than that there shouldn't be to much of a problem. I have been using tube amps for over 40 years and have moved them quite a bit while the tubes were hot and have never had a problem. Actually, in all those 40 plus years I have never had a tube go out on me but I can't say that for transistors.
I have had a couple of solid state amps fry their output transistors on me.
 
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