oops. Left my tubes on for 24 hours. Should I be concerned?

Rischa · « **on:** 18 Jun 2012, 08:02 pm »

I accidentally left my tube preamp on for about 24 hours. I'm not so worried about the tubes themselves, but I am worried that the unit might have been damaged--that's a long time for a piece of gear that gets that hot to be turned on, no? Everything is working as it should and sounding great, but I don't have enough experience with tube gear to know if I might have caused some unseen damage that will make itself evident down the road. Am I worrying for nothing? How long do you guys typically leave your tubes on?

Thanks for your help.

Scottdazzle · « **Reply #1 on:** 18 Jun 2012, 08:09 pm »

That's not a problem. Preamp tubes last a very long time and you did them no harm.

Quiet Earth · « **Reply #2 on:** 18 Jun 2012, 08:37 pm »

When you say " a piece of gear that gets that hot", the first thing that comes to my mind is ventilation. Do you have adequate ventilation for your preamp in the first place? If you do, then you should be able to leave it on for as long as you like. That includes overnight and all week long. For example, my tube dac has 4 tubes in it ( besides some other active solid state parts) and I only turn it off when I go out of town for a long period of time. Even though the tubes inside are turned on, the top and sides of the case always feel relatively cool to the touch. No problems after many years of running it this way.

If the top or sides of your preamp feels hot to the touch under normal use then you should try and ventilate the top (and bottom) of it a little better.

Edit: I see in your gallery you have the Decware preamp. Does it really get that hot? I thought everything made by Decware was supposed to run cool. Now I am confused . . .

Rischa · « **Reply #3 on:** 18 Jun 2012, 08:49 pm »

Quote from: Quiet Earth on 18 Jun 2012, 08:37 pm

When you say " a piece of gear that gets that hot", the first thing that comes to my mind is ventilation. Do you have adequate ventilation for your preamp in the first place? If you do, then you should be able to leave it on for as long as you like. That includes overnight and all week long. For example, my tube dac has 4 tubes in it ( besides some other active solid state parts) and I only turn it off when I go out of town for a long period of time. Even though the tubes inside are turned on, the top and sides of the case always feel relatively cool to the touch. No problems after many years of running it this way.

If the top or sides of your preamp feels hot to the touch under normal use then you should try and ventilate the top (and bottom) of it a little better.

Thanks, Quiet Earth, this is reassuring. The preamp is well ventilated; there's no other gear on top of it, and it sits out in the open on a credenza, rather than in a rack.

It does get warm though. It's a Decware CSP2+, which is tube rectified. I think this adds to the heat (?). The tubes get too hot to touch for more than a second, and the chassis gets pretty warm, too, though not uncomfortably hot like the tubes themselves. I think this is normal, though. I normally don't leave it on for more than a few hours at a time, but this is due more to my inexperience with tubes than anything else. I'm a cautious guy.

sunnydaze · « **Reply #4 on:** 18 Jun 2012, 09:40 pm »

Quote from: Rischa on 18 Jun 2012, 08:02 pm

......... Am I worrying for nothing?

Ummmm.....YES!!!!

It's not an infant in a sealed car on a hot summer day. Good Grief.

Rischa · « **Reply #5 on:** 18 Jun 2012, 09:45 pm »

Quote from: sunnydaze on 18 Jun 2012, 09:40 pm

Ummmm.....YES!!!!

It's not an infant in a sealed car on a hot summer day. Good Grief.

Ok, ok. You sound like my wife.

sebrof · « **Reply #6 on:** 18 Jun 2012, 09:46 pm »

Many people leave tube preamps on 24 x 7, just to give you an idea how much you should not worry about it.

thunderbrick · « **Reply #7 on:** 18 Jun 2012, 09:50 pm »

If you are unsure, I am a qualified audio tech. Send it to me for detailed analysis and I'll let you know in a few months.
You pay shipping both ways, and please include a few coupons for free donuts.

YoungDave · « **Reply #8 on:** 18 Jun 2012, 09:51 pm »

Tubes too hot to touch is OK. Best not to touch them. Chassis or case warm is OK. A standard rule of thumb for designers is that any electrical item should be safe to leave on permanently. Small-signal tubes as in a preamp will last thousands and thousands of hours. Power tubes, perhaps less depending on how hard they are driven.

I turn off my tube power amps (guitar amps) overnight primarily because of tube expense concerns. My tube preamp and dac, I do not turn off except when leaving home for considerable time. My computer and solid state gear, including hi-fi power amps, I never turn off at all.

I am not advising you to manage your gear like I do, just sharing my own power management scheme, which is mainly to leave everything on all the time. That way I do not have to wait for everything to normalize when I want to listen. You will want to devise your own scheme that fits your own lifestyle and meets your own concerns - but feeling that leaving something on a while will cause damage should not be a concern.

JLM · « **Reply #9 on:** 18 Jun 2012, 09:52 pm »

If you're worried, just dump those silly old fashioned tube thingys and get with the program.

Seriously, the tubes might last longer if they're left on (except for vacations). Besides, doesn't Deckert pride himself on basing his designs on cheap tubes? (Maybe even cheaper than donuts.

)

thunderbrick · « **Reply #10 on:** 18 Jun 2012, 09:56 pm »

I'd be more worried about wearing out the on/off switch.............

Quiet Earth · « **Reply #11 on:** 18 Jun 2012, 09:59 pm »

Man, doughnuts sound good right about now . . .

thunderbrick · « **Reply #12 on:** 18 Jun 2012, 10:01 pm »

OK, everybody! Free donuts at Rischa's place!

Rischa · « **Reply #13 on:** 18 Jun 2012, 10:17 pm »

Quote from: thunderbrick on 18 Jun 2012, 10:01 pm

OK, everybody! Free donuts at Rischa's place!

Yep, free soundsgood doughnuts here!

Seriously, I appreciate everyone's reassurance.

And Thunderbrick, I'll send you the Decware for a nominal shipping fee of one mortgage payment.

thunderbrick · « **Reply #14 on:** 18 Jun 2012, 10:20 pm »

Yours or mine?

adydula · « **Reply #15 on:** 18 Jun 2012, 10:37 pm »

No problem....enjoy the music, this is really funny to me but I can understand the concern but your really over worried about nothing...you leave them on for hundreds and hundreds of hours, well ventilated etc....its when you turn them on and off in rapid succession etc...that really 'can' tears things up.

Alex

FullRangeMan · « **Reply #16 on:** 18 Jun 2012, 10:56 pm »

Quote from: Rischa on 18 Jun 2012, 08:02 pm

Am I worrying for nothing? How long do you guys typically leave your tubes on?

Thanks for your help.

No, your concern are real. It is not recommended let tubes amps alone when they are on for much time, as a tube or part inside the chassis may overheat and ...(mainly in power amps).
Other reason:
1 An unexpected power outage during the night or day even(some tube equips are not safe in case of lack of mains power).
2 When the power returns the tension may came back very high.
3 Children, wife or pets may try handle the equip without knowledge.
4 If it is summer tube life may reduce, as heat may built inside the equip too much.
5 If the tube equip use Printed Circuit Board the PCB may be cooked.
6 Your electrical bill may explode...

dB Cooper · « **Reply #17 on:** 18 Jun 2012, 11:23 pm »

#6 made me laugh my ass off

OzarkTom · « **Reply #18 on:** 18 Jun 2012, 11:31 pm »

I used tube pre-amps for many years(20), and I always left them on 24/7.

Except when the lightning storms showed up.

FullRangeMan · « **Reply #19 on:** 18 Jun 2012, 11:38 pm »

Quote from: OzarkTom on 18 Jun 2012, 11:31 pm

I used tube pre-amps for many years(20), and I always left them on 24/7.

Except when the lightning storms showed up.

Uh, seems you are a lucky guy. Recently a lightning burn my CPU and modem for the second time.

(