Genz Benz Shuttle 6.0 misbehaving. Help :-(

[Rich]

My Shuttle 6 was playing up at the gig the other night. Was working fine, suddenly there was a fizzy crackly noise and the volume dropped drastically. I fiddled with the volume control to little effect, then in desperation I thumped the top of the case and the fault cleared. Not the first time it's done the crackly thing, but it's the first time that I've needed to apply the percussion to sort it.
Eeek. Any ideas?

[gary mac]

Maybe the master volume pot, a lot of the earlier models suffered with a dodgy pot. My one had it, mostly a severe crackle but the volume did drop on one occasion, I had the pot on my one replaced, under warranty and all was good for evermore.

[Kiwi]

It's almost certainly a dry solder joint. I've had the same thing happen in other bits of kit.

[brensabre79]

I had this on mine. Cured it temporarily on a gig using impact technology on the top. I sent it back and the replacement did the same thing after a week or two.

It was the valve seating in the rather delicate socket, I changed the 12ax7 valve as a precaution, but do make sure the preamp valve is seated properly, there's a rather feeble spring to hold it in place, but it's liable to move slightly - causing the crackle/low signal.

Edit: I think I've mentioned this in more detail on a thread before so you could do a search on here if you need more info.

[b]TURN IT OFF AND UNPLUG BEFORE YOU OPEN IT![/b]

Edited February 7, 2017 by brensabre79

[Rich]

'Impact technology' love it. A bit like 'percussion engineering'.
Thanks for the help chaps . I've got an enforced month off playing coming up (carpal surgery recuperation) so I'll take that opportunity to have a ferret around inside it and see what I can see see see.

[barneyg42]

[quote name='Rich' timestamp='1486474627' post='3232091']
'Impact technology' love it. A bit like 'percussion engineering'.
Thanks for the help chaps . I've got an enforced month off playing coming up (carpal surgery recuperation) so I'll take that opportunity to have a ferret around inside it and see what I can see see see.
[/quote]

Ferret might be too big, a hamster maybe? Or a small mouse?

[mike257]

Agree that the valve socket is a likely culprit. I changed a few 12AX7s and probably binned some perfectly good ones before I realised taking it out and putting the same one back in worked too! One design weakness in an otherwise cracking amp.