I may have been a silly boy

You been a vewy baaaad boy!!!

Good luck and hopefully it's cheap to fix.

 

Was it plugged into a cab?

 

You do need to be yelled at, and surely will soon enough.
I'd just take it to a good shop. They may yell at you

 

That should not have caused any problem with the amp ....unless you had no cab connected.
If it has a high voltage relay the coil may be too hot? Let it cool for a half hour. Even still it should be okay. What you did was nothing the amp should care less about.

An output tube may have failed but it was going to happen if you left the amp on or not.

 

What happened to it other than being left on?

With the gain turned down and nobody playing it, you could leave it for weeks like that, whether plugged into a cab or not. I've mistakenly done it ( albeit with Fenders ).

Something else went wrong.

Do all the tubes light up? Check all the fuses, etc.? Some amps have internal fuses in addition to the ones on the back. I do not know if an SVT has any internal fuses or not.

 

^this. As long as there was a speaker connected, it should be okie-dokie. Heck, I think turning some electrics on/off is harder on the components than letting it idle for a long time.

 

Ya, I think all you did was accelerate the inevitable demise of a power tube. Nothing that throwing a little money at it won't cure

 

Okay, I'll parade my ignorance and ask - why is it bad to leave it on for three days? Is it just overheating the tubes or is it more complicated than that?

 

If it will make you feel better...yell,yell,yell,scold, scold. But you have no reason to be the recipient of either.

 

And here was me thinking I'd failed Tubes101.1

Does the output transformer suffer if no cab connected but no gain wound on? What if no cab with gain up but no signal?

 

Well even if you're not playing it, heat is still going through the tubes all that time, so there is a bit of wear and tear. Not a big deal if the tubes are happening, but if one's marginal, it could get taken out.

 

If there's no signal going through it or if it's in standby, the OT shouldn't be affected at all. Having said that, it's never a good idea to turn on a tube amp unless a cab's plugged in, just in case.

 

It is not. The tubes will be cooler at idle than in use. On and off cycles are harder on tubes than being left on.

 

I left my Bassman on for a whole weekend once (Friday night after band practice until Monday night). It was on mute , gain on 6 master on 8. It was fine. I may have shortened the life of tubes a little is all. I have left it on standby for days too.

 

my guitar player does that all the time. we'll practice on monday, then when we go to load out on friday his amp is still on. Doesn't seem to harm it one bit, and he's been doin it for years !

 

Careful there Jimmy, if the amp's first speaker jack is a shorting jack and functioning properly, yes (Ampeg and Fender use shorting jacks as an example). If the shorting contacts fail or if it has no shorting jack the repair can be very expensive.

 

Nothing is bad about it, assuming that's all that happened.

Actually, when we get a new tube amp, or put new tubes in one, we leave them on at least overnight, oftentimes longer, and they usually sound better afterwards. They need to "cook" for a while.


Some of that^^ may be a wives tale. I think they sound better when you come back and play them. It could certainly be an ear trick, but it certainly doesn't hurt them. Again, assuming that's all that happened.

 

If there's no signal, the OT should be fine even with no cab connected - not that I'm recommending ever, ever, EVER (there's your yelling. feel better?) doing that. Even with the gain cranked, you would be fine with no cab as long as there's no input signal. But really, don't do this.

 

Even if there's no signal going through the input or it's on standby?