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Tube wear from multiple on/off cycles per day?

Discussion in 'Amp Central Station' started by Ignatius, Jan 23, 2019.

  1. luckett

    luckett Banned

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    If you fully think through your naive assertion that leaving it on won't contribute wear, you're making the claim that a tube or light bulb will never fail if you leave it on. That's a very unique and humorous claim. You should inform the component manufacturers that their products won't fail if left on so they can quit testing their components for service life.
     
  2. bftfender

    bftfender Poster Extraordinaire

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    tube amps off and on all day every day..dsl100h has been on 3 times so far, prob 5 by end of day ..never have had tube problems or longevity issues..and if they do die..get a new one..use the amps !!!..and i cook em pretty good everyday..also usually on 7 hrs a shot in studio sessions...also transport very protected..
     
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  3. King Fan

    King Fan Poster Extraordinaire Ad Free Member

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    :lolol: I'm living in a never-ending standby-pocalypse. :)

    There's no way to kill the darn things; in this case even shotguns are useless. And yeah, they're coming for our brains...
     
  4. King Fan

    King Fan Poster Extraordinaire Ad Free Member

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    upload_2019-1-24_14-19-36.jpeg

    Good find. Love that old (1960) booklet. But, deep in the last chapter (p. 148-150), Mr. Tomer *does* say that power-up surge is a cause of heater filament failure. (Hey, my lifetime of incandescent bulb experience is validated.) :) He even says that in installations with lots of tubes (radio stations, 1960-era computers) it may be worthwhile to look at continuous operation or systems to 'hibernate' the heaters at 50% voltage. He talks about startup voltage limiters or delayers. So the OP's question is valid, and the answer is probably "sure, do what you can to avoid *needless* on-off cycles, but stay calm and don't let it keep you from playing."

    On a practical note, reading those sections, modern, practical steps might be a power conditioner and some way (bucking transformer, variac, zener regulation?) to regulate your voltage and run your heaters at or 5-10% below rated voltage.

    Oh, and read Merlin before you decide that the standby switch is any use at all.
     
  5. teleman1

    teleman1 Friend of Leo's

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    I have 5 tube amps in my small office/mancave. I too, like to play for just a few minutes sometimes. AN that is why I have a Yamaha G-5 with a 6 inch speaker. It is a very well kept secret that is awesome
     
  6. Sconnie

    Sconnie Tele-Afflicted

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    Your answer is hidden in here. He talks about cathode stripping at 2:25.

    He's also very charismatic and knowledgeable if you care to watch more of his channel.

     
  7. peteb

    peteb Friend of Leo's

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  8. Wally

    Wally Telefied Ad Free Member

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    Cathode stripping does not occur in our guitar amps. Twenty years ago or so when the debate about standby switches was making waves, I did some searches on the subject of cathode stripping..and got into some actual engineering papers on the subject. There is not enough voltage to strip cathodes since according to the engineers catjode stripping only occurs at higher voltages...10,000 volts and above.
    Cathode poisoning though is real in our amps when the standby is utilized for long periods....gradual degradation occurs.
     
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  9. Teleterr

    Teleterr Friend of Leo's

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    Many things are better left on/running. It is the surge/ low RPMs ect that wears things out. Theres a light bulb from 1901 thats still burning. Bulbs burn out being turned on, never, IME , while running. A filiment in a tube should be the same.
     
  10. luckett

    luckett Banned

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    That one bulb could simply exist due to survivorship bias. It doesn't prove anything. Could all the others from that same batch have burned out in the first ten minutes? Maybe, maybe not. We don't know.

    If you review what I said again, you'll see that I never said whether it's better left on or switched. I merely stated that leaving it on also contributes wear and @stratclub naively said that it doesn't. It should be obvious to anyone that leaving it on contributes wear.

    As far as whether it's better to leave on or not, I've never seen anyone present a study where anyone has actually tested it. Lots of people are taking a position with an internet quote or by relaying anecdotal evidence, but nobody has referenced an actual comparison test. There must be one out there somewhere since tubes have been around forever.
     
  11. tubedood

    tubedood Tele-Holic

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    I'm in agreement with King Fan on his thoughts of an incandescent light bulb tending to fail on power-ups and using that in this scenario (tube manufacturers such as Sylvania were originally lightbulb makers). One of my first jobs was a projectionist in a movie theatre with the old Christie lamp-house projectors, and between shows the bulbs were left powered on with a solid aperture to block the light for this very reason.

    Dunno if I'd leave a guitar amp on for a year tho! Would encourage me to practice more if I did!
     
  12. jackal

    jackal Friend of Leo's Platinum Supporter

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    When I was in England many years ago, the top line stereo equipment (tube type) didn't even have an on/off switch. They claimed that everything sounded better when it was powered up for at least 72 hours. Don't know why that shouldn't apply to all tube equipment.
     
  13. peteb

    peteb Friend of Leo's

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    That's why I linked the link, this one is called the centennial bulb, and you can even see it in operation




    http://www.centennialbulb.org




    thinking about it, I'm not sure what is more impressive, a light bulb that has been constantly burning for one hundred years, or tube amp tubes that have been in service for more than 50.
     
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