Power Comsumption with Amp on Standby

[bldrst]

Anybody else like leaving their amp on standby and take it off Standby to play throughout the day? I was wondering if having it on Standby is using as much AC as when it's off, i.e. when I play it's draw is 400 watts, is it less when it's in Standby? I don't want to run up my electric bill, so I keep the amp off if I'm not playing, usually. EVH 5150 iii, 50 watt, 400 w draw... Thanks for the input.

 

[jeremy]

Re: Power Comsumption with Amp on Standby

much less but you are probably cooking the heaters more than you need to

 

[bldrst]

Re: Power Comsumption with Amp on Standby

much less but you are probably cooking the heaters more than you need to

Good point, the tubes do have a glimmer while on Standby. I've noticed much less heat from the tubes generally, which is what spurned my question.

 

[SlyFoxx]

Re: Power Comsumption with Amp on Standby

My old pro reverb draws about 50 watts while in standby as I recall. As for cooking the heaters..For years it was my only amp and I left that sucker in standby for like months on end. Basically it was on unless it was being moved. Never had a problem with going through tubes too fast. The 6L6's lasted 5 years easily. When I re-tubed it about two years ago some of the 12ax7's were well over ten years old.

 

[jeremy]

Re: Power Comsumption with Amp on Standby

when the amp is on standby, the heaters are running. when the amp is actually on, the high voltage is applied to the tubes which generates much more heat.

 

[Gtrjunior]

Re: Power Comsumption with Amp on Standby

It only takes about 10 seconds for the proper voltage to rise. I would just turn the amp off between uses.

 

[NegativeEase]

Re: Power Comsumption with Amp on Standby

I wouldn't use standby for anything other than quick warmup at the start, bathroom/smoke breaks when playing or between recording tracks in a recording session, I generally unplug my all of my Vintage amps from the wall (you know, the ones with big old tired filter caps) at home when not in use if not on conditioned and on protected tech power. Lots of thunderstorms at my house and the power grid gets lots of spikes and slight voltage dips in peak usage hours -especially in summer.

 

[ehdwuld]

Re: Power Comsumption with Amp on Standby

I forgot and left my Belair cooking in the other room on standby for almost a month

My light bill was noticeably higher

 

[bldrst]

Re: Power Comsumption with Amp on Standby

All great points. Thanks.

 

[bldrst]

Re: Power Comsumption with Amp on Standby

I wouldn't use standby for anything other than quick warmup at the start, bathroom/smoke breaks when playing or between recording tracks in a recording session, I generally unplug my all of my Vintage amps from the wall (you know, the ones with big old tired filter caps) at home when not in use if not on conditioned and on protected tech power. Lots of thunderstorms at my house and the power grid gets lots of spikes and slight voltage dips in peak usage hours -especially in summer.

Yep. I figured if the current draw is down to a really low draw maybe. That makes sense. Thanks.

 

[Empty Pockets]

Re: Power Comsumption with Amp on Standby

My amp tech told me that standby is for warming up the amp only, and that going back and forth between 'on' and 'standby' causes a lot of stress on the power tubes. Warm it up, leave it on for as long as you're using it, shut it off all at once when you're done.

For breaks up to like 15 mins, I either turn the guitar's volume down or unplug from the amp's input. Any longer than that, just turn it off.

 

[Old Guy]

Re: Power Comsumption with Amp on Standby

Doesn't stand by just turn off the power amp section? Still the same amount of current going to the pre-amp no?

 

[justFred]

Re: Power Comsumption with Amp on Standby

No. Standby turns off B+ voltage (DC) to all the tubes. The AC voltage to the tube heaters remains on for all the tubes.

 

[Old Guy]

Re: Power Comsumption with Amp on Standby

No. Standby turns off B+ voltage (DC) to all the tubes. The AC voltage to the tube heaters remains on for all the tubes.

Wow, I did not know that. Thanks for the info!

 

[bldrst]

Re: Power Comsumption with Amp on Standby

My amp tech told me that standby is for warming up the amp only, and that going back and forth between 'on' and 'standby' causes a lot of stress on the power tubes. Warm it up, leave it on for as long as you're using it, shut it off all at once when you're done.

For breaks up to like 15 mins, I either turn the guitar's volume down or unplug from the amp's input. Any longer than that, just turn it off.

That shut down has something to do with keeping the filter caps healthy from what I remember.

 

[Ayrton]

Re: Power Comsumption with Amp on Standby

My amp tech told me that standby is for warming up the amp only, and that going back and forth between 'on' and 'standby' causes a lot of stress on the power tubes. Warm it up, leave it on for as long as you're using it, shut it off all at once when you're done.

For breaks up to like 15 mins, I either turn the guitar's volume down or unplug from the amp's input. Any longer than that, just turn it off.

This...

John Suhr and Dave Friedman both told me the stand by the switch is pretty useless. I just flip both switches when I fire up the amp and only use the stand by for short breaks.

 

[Gtrjunior]

Re: Power Comsumption with Amp on Standby

My small Blackstar HT-Studio 20 doesn’t have a standby.

 

[oneblackened]

Re: Power Comsumption with Amp on Standby

Power consumption at standby can (roughly) be found by figuring how much heater current the tubes are drawing in amps multiplied by the heater voltage. B9A dual triodes (i.e. ECC8_/12A_7) tubes draw roughly 300mA per tube at 6.3V. 6V6s draw about 500mA per tube, EL84s about 750, 6L6s/5881s about 900. EL34s and their similar analogues (i.e. 6CA7/KT77) are all in the ~1.5A per tube area, as are 6550s. KT88s are 1.6A roughly. Rectifier tubes also use heater current, though usually from a 5 volt tap. 5Y3s and GZ34s/5AR4s draw about 2A of current per tube, while 5U4s draw about 3A.

For an amp like, say, a Soldano SLO, without taking transformer losses into account you're looking at 5 12AX7s (1.5A total) plus 4 6L6GCs (3.6A total) for about 33 watts of power used just by the heaters.
For something like a Blackface Deluxe, you'd be looking at 4 12AX7s, 2 12AT7s (~1.8A together), 2 6V6s (~1A together), and a GZ34 (2A) for around 28 watts of power used just by the heaters.

This doesn't take into account that leaving an amp on standby all the time will severely reduce the life of your tubes - cathode poisoning is a major problem when you leave an amp on standby for long periods of time.

 

[Jacew]

Re: Power Comsumption with Amp on Standby

I wouldn't call standby completely useless: I mean, if tubes are cold I would definitely keep it on standby for few mins before cranking them on their output limit: Running a thing made of metal and glass half hot and half cold simply can't be good for longetivity! It's not deep electrical knowledge, just basic physics.

 

[Ayrton]

Re: Power Comsumption with Amp on Standby

I wouldn't call standby completely useless: I mean, if tubes are cold I would definitely keep it on standby for few mins before cranking them on their output limit: Running a thing made of metal and glass half hot and half cold simply can't be good for longetivity! It's not deep electrical knowledge, just basic physics.

Basically what they were saying is warming up the amp with the "On" switch was the same as using the stand by. I flip both switches and then give it a few minutes to warm up.