Turning on tube amp: leave standby switch on or wait?

[repoman]

Do you leave your standby off all the time and only use it when you want to quiet the amp (like leaving it idle while you change something during a set) or do you turn your amp on with it engaged and then flick it on?

[blakestree]

After powering up the amp, I leave it in standby while the tubes warm up.

[Chankgeez]

After powering up the amp, I leave it in standby while the tubes warm up.

[repoman]

Thats what I always did but read something about this procedure actually being much harder on the tubes (can't remember where)- where not using the standby at all when first turning the power on the tubes experience a more gradual build up of current (dunno if thats anywhere near being technically legit in electronics speak) where as powering the amp up and then flicking the standby has the tubes experience a full blast of current in one shot...and that the standby switch is kind of a relic from the past where its function was a 'beer switch'- musicians would use the standby for quieting the amp after it had been on, as in they go to get a beer.

Any tube electronics gurus here?

[waltdogg]

if buttpussy doesn't have a standby switch why should anyone?

[crochambeau]

Thats what I always did but read something about this procedure actually being much harder on the tubes (can't remember where)

Might have had to do with the type of rectifier the amp has. Most tube rectifiers are somewhat delay start, so everything comes on line gradually (without a "preheat" in standby mode) and no harm is done. Conversely, if you're running a tube rectifier and DO have a standby system, the inrush current that feeds your power supply capacitors can arc/destroy your rectifier.

That is, of course, a pretty extreme scenario, and would probably be indicative of something else being wrong with the amp.

On the OTHER side of the coin, you have silicon diode rectifiers in some amps, and powering those up without your standby "preheat" will introduce B+ to the anodes of the tubes before the filament (heater) has come up to temp, which (again, in EXTREME scenarios) has been observed to accelerate a metallurgical process referred to as cathode stripping - where intentional impurities/coatings in the metal are "burned" via some catalytic process I do not understand enough to even try to explain.

Long story short, both ends of the spectrum are really worst case, I think cathode stripping tends to occur in shit like radio transmitters or radar, where there are many thousands of volts at play.

That said, it really doesn't take a lot of current to kill a rectifier tube, and some audio philosophy veers toward MORE capacitance in the power supple to clean things up. So a good rule of thumb is:

Silicon rectifier: use standby.
Tube rectifier: freeball that shit.

[rfurtkamp]

I've always turned the amp (if it had a standby) with it engaged when powering off and on. Let it sit for a minute or three, go to town.

[Gigahearts_FX]

switch amp on first

then switch on pedlols

then get guitar out of case / fix strap / plug in lead

In that time you can then flick the standby and start rocking. thats what I do anyway.

[duffmcshark]

I remember seeing (not reading) this article before and don't have time to read it now, but I imagine it will tell you everything you need to know about standby switches.

http://peavey.com/monitor/pvpapers/Chapter6.pdf

EDIT: Never mind, I read it anyway.

For those who never use the Standby switch or turn it on too soon after powering up:
"One should always be aware that the REAL reason the standby switch is provided is to switch OFF the high voltage (B+) UNTIL the tubes reach their FULL OPERATING TEMPRATURE, so as to avoid “cathode stripping” of the indirectly heated cathodes of the preamp and output tubes."

For those who leave the Standby switch off for a long period of time while the Power is on:
"...EXCESSIVE USE of a standby switch can cause another destructive process within the tube. If the tubes in the amp are allowed to operate for considerable lengths of time with the standby switch off (no B+/high voltage) the cathode material itself tends to build up a destructive process within itself, and this is referred to as “cathode poisoning.” The “old timers” used to call this phenomenon “SLEEPING SICKNESS!” When a tube is at full operating temperature and no current is being drawn (as is the case with no B+/high voltage) a high resistance layer is gradually formed at the “interface” between the oxide coating and the nickel cathode structure. This layer of barium orthosilicate causes tube performance to degrade significantly. It is important that the standby switch NOT be left in the “off position” (no B+) for more than 15 to 20 minutes at a time to avoid “poisoning” the tube’s cathodes."

[repoman]

Thats what I always did but read something about this procedure actually being much harder on the tubes (can't remember where)

Might have had to do with the type of rectifier the amp has. Most tube rectifiers are somewhat delay start, so everything comes on line gradually (without a "preheat" in standby mode) and no harm is done. Conversely, if you're running a tube rectifier and DO have a standby system, the inrush current that feeds your power supply capacitors can arc/destroy your rectifier.

That is, of course, a pretty extreme scenario, and would probably be indicative of something else being wrong with the amp.

On the OTHER side of the coin, you have silicon diode rectifiers in some amps, and powering those up without your standby "preheat" will introduce B+ to the anodes of the tubes before the filament (heater) has come up to temp, which (again, in EXTREME scenarios) has been observed to accelerate a metallurgical process referred to as cathode stripping - where intentional impurities/coatings in the metal are "burned" via some catalytic process I do not understand enough to even try to explain.

Long story short, both ends of the spectrum are really worst case, I think cathode stripping tends to occur in shit like radio transmitters or radar, where there are many thousands of volts at play.

That said, it really doesn't take a lot of current to kill a rectifier tube, and some audio philosophy veers toward MORE capacitance in the power supple to clean things up. So a good rule of thumb is:

Silicon rectifier: use standby.
Tube rectifier: freeball that shit.

Thanks for the input

It's kind of crazy, you can find different manufacturers saying basically contradictory things about the standby. On sweetwater, there are two articles I just read that say contradictory things- one saying use the standby, the other saying not to!

[zeravla]

Blackout just posted this article to their facebook page. Weird coincidence? http://wamplerpedals.com/should-i-put-m ... ialnetwork

Your standby switch is a hangover from Fender being more interested in the early days of repair and servicing. In terms of normal playing, in a normal amp, your standby switch is pretty useless. It’s just there as we guitarists expect it. Your amp will probably sound better after a few minutes once everything has warmed up and settled down. Cathode Stripping, do you want to risk it? I don’t, so I won’t be leaving my amp on standby when I’m not playing it. I’ll just turn it off (as like most people, my amps sits in that fraction of a millimeter between “Can’t hear it?” and “Ermhagerd!” so turning the volume down isn’t really an option). Please do not turn your amp on at all without the speaker plugged in and please – if you love your amp – give your valves a few minutes (minimum) to cool down before moving your amp after use. And, of course, there are no user serviceable parts inside – leave it to the professionals!

[rfurtkamp]

Truth is that the old-timer advice in the stone age varied substantially by region (myths abound!).

I do the standby on for on/off power cycles because that's what I was instructed to do when playing through *any* of the old valuable amps of the time at my favorite vintage shop, and well...if they were going to let 20 year old me fuck with *anything* in the place, I was going to do exactly as they recommended.

[resincum]

I use the standby on my carvin when warming up, idle time and powering down.

I only use the standby on my v4 when powering up, but never idle. I flick it off when the amp is off as well. something about cathode poisoning and old tube amps or some hoohah

[waltdogg]

if it's there use it as you see fit. but what crochambeau said sounds about right to me. i'm also in the same camp as rfurtkamp and resin cum, no way in hell amp i'm just turning on a vintage amp without warming it up. as for shutting it off just do warm up process but in reverse.

[crochambeau]

i'm also in the same camp as rfurtkamp and resin cum, no way in hell amp i'm just turning on a vintage amp with(OUT) warming it up. as for shutting it off just do warm up process but in reverse.

I think that edit I punched on your statement is in line with what you said?

Regarding VINTAGE amplifiers, this is absolutely correct. I also operate standby if available (though I don't worry as much about shutting it down), though I'm trying to think of an amplifier I own that has a standby & tube rectification and I'm drawing a blank.

The potential issue, as I see it, AND I MAY VERY WELL BE CHASING SHADOW PUPPETS, involves modern builders or modifiers. There is an AWFUL lot of aping going on in the electronics industry, and sometimes designs are not exactly plotted from the desk of an EE... so, when you get a marketing driven (or otherwise poorly thought out) product it is highly possible that someone could design or modify an amplifier that is tube rectified (because the spirits of tone told me to) with way too much capacity available for ripple filtering the power supply (because more filtering equates to cleaner power, maaaaaan; just ask an internet audiophile) that carries a standby switch because it is standard you could have the beginnings of a recipe for failure.

Obviously, the above paranoia does not apply to many. But I've seen some frightful shit passed off as "knowledge" and because that pool is polluted I have a hard time sticking my THIS IS THE ONLY WAY IT IS DONE brand sticker of approval on anything any more.