Volume dropping out

[jimi]

Had some gear drama at a gig last night with my volume dropping out and coming back.

One of those intermittent ones, that’s fun to troubleshoot - skipped the pedals and went direct and was okay for half a song, but dropped out again, swapped the lead, okay for a bit then started again, different outlet on the power block, still bad, swapped guitar, good for about 5 songs, then it started again.

Eventually pushed on the tubes to make sure they were well seated, and swapped to a different power board during a break, and no dramas in the 2nd set. Gig went well and crowd didn’t seem to notice, but it’s the kinda of stress you don’t want at a gig.

Playing the Greenstone Bellbird which has always been solid, so much that I don’t carry a plan B anymore.

Any ideas on what it could be? Worth getting the amp checked? Who would I take it to in Auckland now? Ryan serviced it when I got it, but that’s not an option now.

[jeremyb]

Can be just as simple as a loose toob, usually these sorta things only get worse not better so you might have dodged a bullet!

On the other hand whens the last time it had new toobs? might be a good reminder to freshen her up, Mat has 15% off at the moment!! https://tonelounge.co.nz/amp-tubes/

[higainer]

Dodgey tube perhaps,
That’d def give me the shits at a gig.

If Clarry is too snowed under try Ivan at http://www.musicelectronicsrepair.co.nz
He’s in West Auck.

[jimi]

Cheers! Good to hear Clarry is still doing his thing.

New tubes in 2014. Don’t know if that’s long or not, it’s the only amp if ever bought new tubes for.

Will give everything a decent hoon at home and see if I’ve got the gremlins sorted. Must get one of those direct to PA pedals for the gig bag.

[AiRdAd]

the sound guy fucking with you?

[jimi]

Haha.. I'm just stoked that you think I have a sound guy!

[Slowy]

Was your amp mic'd to a PA? Had that problem once and the amp mic was out of phase with everything else.

[MikeC]

Reads to me that you've proved it to the amp. Get amp checked out

[Polar Bear]

Cheers! Good to hear Clarry is still doing his thing.

New tubes in 2014. Don’t know if that’s long or not, it’s the only amp if ever bought new tubes for.

Will give everything a decent hoon at home and see if I’ve got the gremlins sorted. Must get one of those direct to PA pedals for the gig bag.

If you’re gigging regularly with the amp, 6 years is a long time for valves. You’d be wanting to change them every year or so ideally.

[MikeC]

Particularly the output valves.

[NippleWrestler]

It could be a tube. But when this happened to me it was the output transformer. Granted this was a laney from the 80s but a change of tubes for new ones didn't help because that wasn't the issue.

A tech who knows his stuff should be able to help if they check the voltages of the circuit.

Aren't greenstone based in NZ? Perhaps they could help you out.

[MikeC]

Just a final thought - an intermittent speaker connection can lead to output tube & OT issues/failures. Check the spade connectors or soldering at the speaker end and check soldering at the plug end.

[rickenbackerkid]

Worth checking FX loop plugs too - I had a Marshall which started dropping in volume and in the end the issue was dirty jacks in the FX loop. I cleaned them and left a patch cable plugged in to keep dust and dirt from getting it, that amp is still OK and being used by my brother.

[Bg]

No loop on a bellbird

[RectifiedAmps]

It sounds like worn out output tubes. Wait for the amp to warm up and then give each one a couple light taps- if there’s a problem you’ll hear crackling and possibly even see some fireworks inside the bottle! If this turns out to be the issue, don’t waste any time replacing them - when they fully short they can take out other parts- resistors or even the output transformer, if there’s not any fusing.