Leaving tube amps on all day?

wabashslim

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I thought this was going to be about tube amps - not "tube" amps.
My solution for my old AD60 V-tronix was to turn it off & leave it off until the next owner faced that decision.
 

Synchro

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As an earlier post, mentioned, there were plenty of electronic devices in the tube era that kept the filaments heated 24x7. There were TVs advertised as “Instant On”m as one example. I shure wouldn’t worry about that harming tune life, and the filament of a lone 12AX7 probably draws less than a night light. That having been said, I can’t think of any reason to leave it on all the time.
 

Ronkirn

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OK.. what many are overlooking is WHAT leaving it on is supposed to do.... Perhaps a review of the past 20 years of the Audiophile's "bible" "The Absolute Sound" would help.. https://www.theabsolutesound.com.

In that world the ultimate Stereo sound system, (these easily cost $500,000.00 and up) will recreate a number of effects not really related to "sound quality". Among those are things like imaging, or being able to hear the different Rows of Clocks in Pink Floyd's recording... That's a fascinating experience..

It also allows you to hear the position of the first Violin, or a Cello in a Corelli work, or any of the other instruments in an orchestral presentation... IF the recording is "up to snuff". That usually eliminates CD's and Mp's..

If listening to a vocals you can hear where Peter, Paul, or Mary are standing.... Or where Lindsey, Stevie, Christy or Mick are positioned on the stage in a live recording..

Or it enables you to hear the "slap" of a Bass Drum Pedal as it hits the skin... the transients of the Hi Hat or a cymbal.

and YES you can indeed hear such definition... you just can't hear it listening to an Mp3 on your iPhone... or on some skanky home entertainment system.. it takes a room engineered for sound, and the quality "gear" necessary to duplicate such an experience.

In such, the gear is left on because it enables the gear to articulate 100% of whatever capacity it's capable of... and remember those systems reproduce sound across the full bandwidth of sound, 20 to 20,000 hZ . Your guitar's amp has a "governor" built in.. the speaker . . . where the better drivers only reproduce from around 30 to 6000 hZ.. hardly enough of the spectrum to matter much...

I might mention.. in the past 20 years, digital tech has gone far to reproduce such sound from stunningly simple appearing speakers.. but still nothing compares to something like a couple of Mono Block Audio research Amps being pumped by an AR Preamp.. while spinning a 180 gr master recording on a SME turntable.. with a VPI Tone arm fitted with a Clear Audio Goldfinger... feeding a pair of JBL Everests ( to pick a brand recognizable to many) .. and add 15,000.00 for the cables to hook 'em up... not to mention the 100 grand to re-do the whole room in which such a system will be installed...

Now swallow hard.. for anyone brave enough to look up what that stuff costs.. that represents ONLY the most BASE of an entry level system... or, . . . that's nuthin'... To reproduce the London Philharmonic as heard from center row 7 . . . in your listening room would easily cost what a really fine Home would set ya back...

and that's why so much of the "arguing" about guitar tone in the forums is much like a bunch of 7th graders arguing about video games in a school yard... they just have no idea about what lies beyond...

So as I said... turn it on when needed, and off when not, and practice... that'll make a real difference in how ya sound..
 

Telekarster

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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.
 

northernguitar

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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.

Nice to know I’m not the only one. ;)
Power bar with surge protection will make that moot.
 

Ronkirn

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A lightning strike could jump the gap between a powerbar’s switch contacts.
yep.. sure 'nuff can... back in the 90's I did a lotta volunteer work helping the United Way Agencies with their computers... They're all grossly underfunded.. so they would buy the least expensive "power strip" they could find...

Every Summer as one of those good old afternoon thunder storms rolled through, someone would call .. their computer got blown across the room.. (that's an euphemism for the pedantic out there) but got zapped out of commission..
 

jdl57

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I just reread your post, and looked up the circuitry of your amp. It is a solid state design that uses a 12AX7 as a preamp tube to drive the amplifier section. 12AX7s are cheap and common. Do not worry about your tube. I leave solid state on all of the time unless I will not be using it for a while. Further explanation below:

People are way over estimating how much power an amplifier uses. I have an old Fender tweed Princeton. Single ended Class A circuit, one power tube, which means it is drawing full power all the time it is on--amplifying or not. A Class AB push-pull circuit, 2 or more tubes, pulls significantly less power when not amplifying. My 5 watt Princeton uses 22 watts of power when it is on, a little less than 2 night lights. Do any of you worry about the cost of running night lights? I have a pair of mono power amplifiers on my stereo. They are Class A and draw 400 watts each when they are on. I figured it out once using my kilowatt hour price at the time, probably more now, and I came up with 15 cents an hour to run the two amps, 800 watts total.

A tube works by heating up the cathode, thereby producing a field of electrons. They are drawn to the anode, which has been positively charged. This flow is on whenever the amp is on. The flow from the cathode to the anode is controlled and modulated by 1, 2, or 3 grids between the two, depending on the type of tube. the center grid(s) are powered by the input of your signal from the pickups, which are actually tiny generators.

Since electrons are being produced all the while the tube is powered, and there is a finite amount of electron producing material in the tube, yes, it will "wear" out. While that doesn't shorten the life of the tube, it will use up a lot of that life when you are not using the amp. The other side of the coin is that tubes need to warm up and become thermally stable to sound their best, usually a couple of hours. This is mainly and audiophile problem. Your amp will sound just fine when you first turn in on, it will sound better a couple of hours later. What do I do? I turn off my tube gear when I am not using it. Some of my power tubes cost hundreds of dollars. On the other hand, I have a Fender Jazz King solid state amp that I never turn off.
 
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Telekarster

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A lightning strike could jump the gap between a powerbar’s switch contacts. Unlikely? Absolutely — but possible.

(I make a living devising worst-case scenarios)

Sure can... I had this happen once and it fried my stereo receiver! I was ticked.... LOL!!! :eek::oops:o_O
 

JIMMY JAZZMAN

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BTW, Those instant on TVs from the past, seemed I was always going to the drugstore for
my dad, to check tubes and purchase new ones. Oh, instant on for sure but a pain, plus
it weighed more than a Vox.....maybe 2 Vox's.
 

Big Slammin

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I used to work in the cathode ray tube industry, projection tubes for flight simulators. Same principle of operation and materials as audio tubes.

Risks for leaving the tubes on all the time are eventual evaporation of the oxide cathode coating and random AC line transients. Maybe aging of capacitors and other components via thermal aging.

Cathode evaporation will take a long time, not too much of an issue. The open structure of an audio tube is more forgiving, there are apertures (small holes) in the grids of a CRT that can clog with evaporated material, changing performance. This is accelerated when the electron beam is on, painting the picture on the CRT - becomes dimmer and not as clear. Less concern on an audio tube due to structure but you will have less life over time if always on. Maybe not much practically speaking.

Thermal stabilization of components is two parts. Just letting the heaters run and the voltages sit for awhile (30 minutes or so?) May make a slight difference in consistent tone. However, heat in transformers, tubes and other components increases much more when signal is passing through the chain. Heat from power dissipation in each device and combined heat from all devices in the enclosed space. Playing an amp loud for some hours. Goes to component life and possible changes in tone due to component drift.

AC line issues are simply the odds of transients when an amp is powered up. When it is on and connected to an outlet constantly you have more chance to experience it. Rare in my experience, depends on your local grid.
 

MuddyWolf

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Back in the 60s, dept stores like Woolworths had all tube PA systems for sale announcements and clean up on isle 10 type stuff. They left those on for days, years, and decades. They probably never turned them off except by accident.

However guitar amps ain't ducane PA systems. PAsytems were made to stay stable and sound clean. Tube amps are made today to be run hard and distort.

If you left your tube amp on for the weekend and it still works, cool. I'm not surprised. If it doesn't work I'm not surprised either.

As for the vox amps with one preamp tube, you could leave that on forever. It is probably better to be left on then to turn it on and off.
 

arlum

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In my studio, when I'm going back and forth between playing and recording, I leave the amp on in standby. Sometimes for as much as an hour or two. That said ..... I would never leave it unattended for more than maybe a half hour if I had to leave the studio to attend to something else.
 

swarfrat

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My wife is one of those there can only be lights on in the room your in. But she won't budge 1 degree on the thermostat. I figured it up and leaving every light in the house on all month is like $20-30. That 1 degree difference costs two hecks of a lot more

With the tube situation though that's what I'd be most concerned about. Don't cut them on and off all the time (inrush) but don't leave them on unused for hours either
 

teletail

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Does anyone actually know how much electricity an amp left on all day uses and how much it costs? You know, an informed opinion? For the record, I don’t leave my amps on when I’m not using them; I just need a little more information before I vote for the death penalty for leaving an amp on.
 

corliss1

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@teletail - This wouldn't be hard to figure out. Let's say we have a tube amp with a 100W current *draw* from the wall. Maybe that's our 18-25W amp or something similar. Whatever, doesn't matter.

My local electricity is $0.1478 per kilowatt hour for the "summer" rate. If we're consuming 100W that's .100 kilowatts, so that makes the math easy.

We're using 0.100kW x 24 hours = 2.4kilowatt hours

0.1478cents x 2.4kWH = .35cents

For one year, that would be about $130.
 

Euphonica

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I have an amp meter on my bedroom setups, and with the Twin + 6g15 it uses .9 amps, the Bassman + 6g15 uses .6 amps. That’s at idle. When playing loud it creeps up a few amps here and there, but never much more. I never turn it up past 10 o’clock.

Once I left the Twin on for weeks, and it does seem to have shortened the life of the sweet NOS tubes, but otherwise nothing remarkable. Electricity bill wasn’t different. This was a few years ago. I now turn them off when I’m done.
 

teletail

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@teletail - This wouldn't be hard to figure out. Let's say we have a tube amp with a 100W current *draw* from the wall. Maybe that's our 18-25W amp or something similar. Whatever, doesn't matter.

My local electricity is $0.1478 per kilowatt hour for the "summer" rate. If we're consuming 100W that's .100 kilowatts, so that makes the math easy.

We're using 0.100kW x 24 hours = 2.4kilowatt hours

0.1478cents x 2.4kWH = .35cents

For one year, that would be about $130.
Ok so if you left it all day, every day, and shut it off at night that’s about $5 a month. Hardly a convincing argument from those coming at this from a financial angle.

Again, I do shut mine off.
 




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