How long do you leave your amp on standby?

[crusty philtrum]

Re: How long do you leave your amp on standby?

Those little aluminum thingies are to protect the tubes from damage.

That is a secondary advantage of the metal covers ... their prime function is shielding, and is primarily used for early preamp stages and other sensitive areas where it is highly desireable to keep extraneous noise to an absolute minimum.

 

[GuitarStv]

Re: How long do you leave your amp on standby?

When it's in standby, only the heaters in the tubes are running, so it's like running a radio all day long. The tube wear occurs in non standby mode.

One time, I left my Gibson Goldtone in standby for 3 months! It's because the 3 way on/standby/off switch is on the back of the amp and hard to notice. The tubes sounded just fine since then. That showed me that it's nothing to worry about.

What you DON'T want to do is keep it in running mode for days on end. Then, you will heat up the amp, and probably fry your tubes.

It's the heaters running that cause the problems with the tubes. The heated cathode throws off electrons. The electrons are usually pulled away by the anode, but when the tubes are on standby the electrons are all just bumping around the cathode, stripping away the cathode coating and reducing the efficiency of the cathode itself. (Cathode poisoning). I have no idea how long this process takes though, or how to compare it with themal shock from playing tubes immediately after turning the amp on.

FWIW I've got a couple guitar amps from the early 60s with no standby switches. One of them still works fine with the original 50 year old General Electric tubes in all positions . . . so I figure that turning an amp on and letting it warm up via standby can't be that important for tube life.

 

[SlyFoxx]

Re: How long do you leave your amp on standby?

FWIW I've got a couple guitar amps from the early 60s with no standby switches. One of them still works fine with the original 50 year old General Electric tubes in all positions . . . so I figure that turning an amp on and letting it warm up via standby can't be that important for tube life.

I'll give 10 to 1 those amps have a tube rectifier. It warms up slowly so the rest of the amp has to as well and doesn't get hit hard with the full power from the wall socket.

 

[beaubrummels]

Re: How long do you leave your amp on standby?

I will leave an amp on Standby for anything less than an hour, but power down if I'm not going to play within an hour.

My general sequence:
1. Power on, leave in Standby at least 60 seconds
2. Play
3. put in Standby for at least 60 seconds
4. then Power off.

Never Power on with the amp not in Standby. Let the heaters warm the tubes before taking it off Standby. I don't know that putting it in Standby before Power off is necessary. I just always power down in reverse sequence for every piece of gear I own. If I make it a general habit, then it's safer for when it does matter.

 

[Hank-]

Re: How long do you leave your amp on standby?

FWIW I've got a couple guitar amps from the early 60s with no standby switches. One of them still works fine with the original 50 year old General Electric tubes in all positions . . . so I figure that turning an amp on and letting it warm up via standby can't be that important for tube life.

Actually last time I checked up on this I found that the idea of standby switches in guitar tube amps was borrowed from some other equipment. But those equipments needed them more because the voltages were supposedly in >1kV range.

When I turn my amp on for the first time for the day & keep it in standby, the tubes don't really get super hot. They get warm & that's about it but it's when the amp is running that's when they get hot enough to fry eggs on :laugh: The winter season in my place is hardly something I'd call cold, the lowest temp I've noticed is 25C & that is if I'm really lucky. So, thermal shock is the least of my worries But I do wait for a minute before taking the amp off from standby & start playing.

One thing where the standby switch is highly useful for is I think to check if an amp head is connected to a speaker cabinet during that 60sec period of warm up.

When turning the amp off, I just flip the standby switch first & then the power switch. No 60sec wait or anything that I do but I do wait for a while like 5min or longer once the amp is turned off, before moving the amp from its position.

 

[GuitarStv]

Re: How long do you leave your amp on standby?

I'll give 10 to 1 those amps have a tube rectifier. It warms up slowly so the rest of the amp has to as well and doesn't get hit hard with the full power from the wall socket.

They are tube rectified, but there are plenty of amps with tube rectifiers that have standby switches. Actually, both the amps I've got with standby switches have 'em. Is it superfluous for these designs?