A shot in the dark, but...

dogload

... last night at band practice I was getting unusual noises through my speakers. Bad unusual crackly noises, that sounded exactly like a broken guitar a guitar lead. Now, the question is, is it something in my amp (Selmer Treble & Bass) that's loose or is it a sign that a valve is on it's way out? I should add that the noise occurred when I brought in a particularly beefy sound (like a more bassy tone or using my Superego pedal) or when I had a fair bit of delay and drones going on together.

I know it's a bit of an abstract question, 'is there something wrong with my amp?' and I haven't ruled out a dodgy bit on my pedal board, but there was no cutting out. Just the buzzy, farty dodgy lead sound. I checked the leads and they were fine btw Any ideas before I a) l pull my board apart or b) waste money taking my amp to be mended unnecessarily ?!

SunDevil

It sounds like a loose electrical connection by your description - a few things you can DIY to rule out basics

1) Suggest you plug direct to the amp to rule out anything 'upstream'

2) Get yourself something pointy and insulated (wooden chopstick for example) and gently tap the valves and the Jack connections when in play mode and see if you can find the culprit

3)If you have spare valves - pop them in and see if that solves the problem

dogload

@SunDevil thanks for the suggestions. I'll give them a go asap. Much appreciated

ICBM

It could be either a bad valve - almost certainly power, with an intermittent arc that's vibration-induced - or a bad connection somewhere in it, or -

 - hopefully not, because this would be a serious problem, but I have come across it before including in a Selmer… an internal arc in the output transformer which needs a particular signal strength to trigger it. My DIY valve-testing rig was once a Selmer 100 PA amp with this fault.

But check and eliminate everything else first before assuming that.

dogload

@ICBM

Thank you