Leaving tube amps on all day?

Red Ryder

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Turn it off and on, off and on, off and on, off and on, off and on. The hell with work, you must turn the amp off and on, off and on, off and on, off and on...............
 

Rick330man

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In the realm of high end audiophiles it's not at all uncommon to find leaving tubed amps, preamps, etc., on 100% of the time... the general assumption is, doing so results in superior overall sound... and since there are no myths, no totally outrageous claims for whatever aspect of an Audiophile's system you care to mention in that world.. you can bet it's true.. :rolleyes: just don't bet much..
They'd be on All Day And All of the Night!
 

dsutton24

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When you're thinking about electronics it's useful to forget about wearing things out. Wearing out implies degradation over time, and is somewhat predictable in things that truly do wear out. Think instead about things failing unexpectedly. How many things in an old amp could fail and case a fire, lots of smoke, or moments of panic?

Shut it off when not in use.
 

El Tele Lobo

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Personally, it would make me nervous to leave a piece of high voltage equipment on all the time... Let's face it, it's a box full of stuff that could fry and if it should happen to fry when you're not around, bad things could happen. I say turn it off when you're not using it. Also, I read that it's not even a good idea to leave an amp plugged into the socket i.e. a power surge could fry the amp. Therefore, I not only turn mine off but I unplug em from the wall as well.
+1
 

Jimclarke100

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The 12AX7 in a Vox AD30VT is run in starvation mode anyway, maybe 30v anode to cathode, so leaving it on probably has little impact on its life. As noted before, it is used to help simulate a power amp response rather than in any stressed state so it’ll probably be fine.
 

Deeve

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Same as w/ the stove - leave it on all the time, whether we're scambling eggs right then, or not...
Always ready
 

DekeDog

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I usually only have my amp on when I'm using it, and even then, it's mainly used in a studio environment... rarely "cranked". I have on occasion, inadvertently left the amp on "standby" overnight when I forgot to turn it off. In this day of the reduced availability and high price of tubes, I am concerned about the lifespan of my tubes. Does leaving an amp on standby overnight have much affect on the lifespan of a tube?
 

Telenut62

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I usually only have my amp on when I'm using it, and even then, it's mainly used in a studio environment... rarely "cranked". I have on occasion, inadvertently left the amp on "standby" overnight when I forgot to turn it off. In this day of the reduced availability and high price of tubes, I am concerned about the lifespan of my tubes. Does leaving an amp on standby overnight have much affect on the lifespan of a tube?
Cathode stripping should not be confused with cathode poisoning. Cathode poisoning refers to chemical –rather than mechanical– processes occurring at the cathode. There are several forms of cathode poisoning, including absorption of gas into the oxide coating, but the most pernicious type is the growth of interface resistance. When a valve cathode is fully heated but no anode current is allowed to flow for long periods of time (several hours), a high-resistance chemical layer can grow between the cathode tube and the oxide coating. This has an effect like an unbypassed cathode resistor; it increases noise and reduces the useful gain of the valve even though the oxide coating may have plenty of life left in it. This really does happen in receiving valves, and once formed it cannot be removed again.

 

Southboundsuarez

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Heat is a byproduct and is conducive to premature failure.
The only argument for not powering up is the perceived threat of inrush current causing damage to your filter caps.
Regardless, especially in your application heat is a bigger threat than inrush currents.
Your amp isn't even really a tube amp but a solid state amp with a tube driven preamp. Most of these solidstate power amps with a tube preamp usually have the tube component buried inside the non serviceable consumer based chassis that it's set and forget for the useful life of the product.
I think that these types of designs usually are poorly vented and already are suffering for excessive heat generated by the buried thermonic component inside.

My own prudence for electrically operated appliances is to not only turn them off when not in use but I also prefer to unplug from the mains any appliance unsupervised at any length of time.
 

Southboundsuarez

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Cathode stripping should not be confused with cathode poisoning. Cathode poisoning refers to chemical –rather than mechanical– processes occurring at the cathode. There are several forms of cathode poisoning, including absorption of gas into the oxide coating, but the most pernicious type is the growth of interface resistance. When a valve cathode is fully heated but no anode current is allowed to flow for long periods of time (several hours), a high-resistance chemical layer can grow between the cathode tube and the oxide coating. This has an effect like an unbypassed cathode resistor; it increases noise and reduces the useful gain of the valve even though the oxide coating may have plenty of life left in it. This really does happen in receiving valves, and once formed it cannot be removed again.

That is an interesting tid bid of information..... As somewhat a collector and scavenger of old, used and vintage antique tubes, this makes perfect sense.
So many consumer electronics of past would utilize tubes that would just sit idle and cook for days on end.... Now sometimes some of these old appliances are being discovered and scavenged for their old tubes. These old tubes find their way into circulation such as flea markets and such... I get many old antique tubes that I like to use, especially the standard fare of preamps such as 12**7 triode types. They usually will test ok for emissions on tube testing equipment, even transconductance testing. But they have their own special personalities. Fizzes, white noise and even an occasional "EVP" probably from some dearly departed in it's previous useful life*. ( Never anyone famous and certainly not any guitar artist! ) Awwww shucks!
But seriously, I can tolerate some of the character of an antique tube in my own gear, but I can't confidently put an old vintage tubes to use in a customers gear. I usually will only use used vintage in collectable vintage gear for period correctness. I just cringe to see JJs in say like something such as an old tweed. Maybe even a Blackface.....
Probably a bit late and off topic but felt like commenting on the probability of this effect of cathode poisoning and old tubes.
*BtW... I am just kidding 'bout the EVP's , I particularly don't believe in such Paranormal Reality Television Show nonsense and their novelty electronic ghostbusting gizmo and gadgetry!
My wife does, and those shows bug me, as you might imagine from my post!
 

radiocaster

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I would not recommend it if it's particularly hot where the amp is. Bad for electronics in general.
 




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