what do you mean, standby not needed?

[anson]

I've got a mute switch (shunting signal to ground) in my amp, and it does it's job well. I don't get the pops and stuff that a typical stand-by arrangement has. The switch is just before the PI, where the master volume is. Now that I think about it, I guess that makes the mute switch just a lazy way of turning the MV down inbetween songs.

[imaradiostar]

I don't have problems with standby switches making noise ever since I started putting them between the PT secondary and rectifier inputs. I did manage to destroy a SPST switch the other day hot-switching 600 volts DC at about 600ma while I was testing power transformers!

In light of things people have said here I've stopped worrying about standby switches on old amps that aren't equipped, especially if they're tube rectified- the rectifier is going to soften the blow to the other tubes anyway since it likely will have "controlled warmup time." Many of my builds end up getting used in church/worship situations where a standby is can be crucial to being quiet and ready to play when a prayer or sermon is over...but not accidentally rocking out or making cable noises before it's time!

jamie

[soundmasterg]

Just what we need...an amp that just up and automatically mutes itself.

It would be really funny to wire up something like this remotely for the other guitar player in the band, and right when he was going to take a solo, you flip the mute switch....haha.

I'm of the opinion that standby is useful as a mute condition, but isn't needed in receiving tube amps. There are a number of ways to do standby to make the power tubes not work as hard as when they are idling, (screen or cathode standby in addition to the traditional B+ interrupt) but there are also ways to mute the signal such as those already mentioned that accomplish the same thing as far as the guitar player on stage is concerned.

Greg

[ThermionicScott]

I like Merlin's compromise solution: wire a high-value resistor across the standby switch so that a trickle of current is always flowing. Allows you to mute the amp, get rid of the inrush surge, and stop worrying about cathode stripping/poisoning (if you were).

- Scott

[Albert Kreuzer]

Found this in an old German amp (late 60s). Keeps the first cap charged at a lower voltage.
The only downside is you need a 2pole switch.

Cheers,
Albert