When to pack up valve amp

lincolnblue

So after using a valve amp for a while it naturally gets hot. How long should you leave it, having turned it off, before moving it or putting an amp cover on?

ICBM

Preferably until the valves have cooled down - five minutes should be enough. They're a bit more fragile when they're hot, so it isn't a good idea to bump it around before that if you can avoid it.

lincolnblue

ICBM said: 

Preferably until the valves have cooled down - five minutes should be enough. They're a bit more fragile when they're hot, so it isn't a good idea to bump it around before that if you can avoid it.

Thanks. I left it about 10-15 today. It was still a little warm but seems ok

RiftAmps

In theory? The filaments inside valves are only brittle when current is passing through them, so a valve amp can be moved as soon as the valves are no longer glowing (22 seconds after switching off).

In practice? I like to leave it a few minutes, enough time to pack the guitar away and roll up a few leads. This ensures that everything else has had a chance to cool down somewhat and that the singer is out of the way and at the bar.

ICBM

It’s also not necessary to put the amp on standby to ‘allow it to cool down before turning off’ as you may sometimes read. It’s only a good idea if you’re not sure you aren’t going to be asked for another encore .

It will actually cool down faster if you just turn it straight off.

lincolnblue

ICBM said:

It’s also not necessary to put the amp on standby to ‘allow it to cool down before turning off’ as you may sometimes read. It’s only a good idea if you’re not sure you aren’t going to be asked for another encore .

It will actually cool down faster if you just turn it straight off.

That's useful to know. I assumed you had to leave it on standby for a few mins. Thanks

Modulus_Amps

ICBM said:

It’s also not necessary to put the amp on standby to ‘allow it to cool down before turning off’ as you may sometimes read. It’s only a good idea if you’re not sure you aren’t going to be asked for another encore .

It will actually cool down faster if you just turn it straight off.

I never even knew this was a thing...

ICBM

lincolnblue said:

That's useful to know. I assumed you had to leave it on standby for a few mins. Thanks

It's probably worth remembering that people have been 'mistreating' valve amps by not using the standby switch for about 60 years, and before that none of them had standby switches anyway!

But - bear with me, this is about to get technical - it *is* a good idea to always put an amp on standby for a short time when you power up, if like yours, it has a solid-state rectifier. This is not to protect the valves, but the filter caps - a solid-state rectifier doesn't need time to warm up, so the full high voltage will be applied to the caps when the valves are still cold and not conducting, and you will stress the caps much more than if the valves are drawing current, which reduces the voltage.

An occasional fault on the Hotrods is the last filter cap failing - when I first noticed it as a recurring fault I was puzzled as to why, since it's the one that has the lowest voltage on it, but (I think it was jpfamps who pointed this out) caps have a 'memory' to some extent, so if this cap gets used to operating at the lower voltage and then you turn on without using the standby and hit it with a much higher voltage, it can then fail. It's still fairly rare, but if you can avoid it by always keeping the amp on standby for at least thirty seconds when you power up, it's better to.

JayGee

Power everything down, wipe down and pack up guitar(s), unplug and pack up pedalboard, unplug, coil, and pack up leads (mains first, speaker last, assembly is the reverse of disassembly). By the time you’ve finished that lot the point is moot as the amp’s pretty much completely cooled anyway.

Well that’s how I’ve ended up doing it anyway, more in the interests of getting the most vulnerable stuff safely tucked away first than out of any consideration of the amp cooling down but it works anyway...

Vinylfan

This is all useful advice.  When it comes to powering up, does it matter where the Volume control is?  Whether that's Master Vol or not?  I was told to keep the Volume control down/off when powering up a valve amp - good advice or makes no difference?

Thanks

ICBM

Vinylfan said:

This is all useful advice.  When it comes to powering up, does it matter where the Volume control is?  Whether that's Master Vol or not?  I was told to keep the Volume control down/off when powering up a valve amp - good advice or makes no difference?

Bad advice. It simply increases wear on the pot.

Vinylfan

ICBM said:

Vinylfan said:

This is all useful advice.  When it comes to powering up, does it matter where the Volume control is?  Whether that's Master Vol or not?  I was told to keep the Volume control down/off when powering up a valve amp - good advice or makes no difference?

Bad advice. It simply increases wear on the pot.

Ok so just leave it where you want? 

ICBM

Vinylfan said:
Ok so just leave it where you want? 

Yes, leave all the controls where they are.

Vinylfan

ICBM said:

Vinylfan said:
Ok so just leave it where you want? 

Yes, leave all the controls where they are.

Thanks 

timmysoft

I packed up my valve amps when I got the helix !! 

Gadget

If it’s in an enclosed flightcase, I always insert a silica gel sachet in the case too, so that there are no condensation problems.