Rig volume fade issue

Hi all,

Last night my rig volume was fading in and out. I'm desperately hoping it's not an amp / valve issue.

All of my pedals are powered by one spot daisy chain but there is an EHx Pulsar 12v pedal in the chain that I didn't bother to plug in. Could this be the issue? ie having an un powered pedal in the chain that the signal passes through? or are there consequences to this in terms of buffering? or could it be something else?

I suppose it could be a cable, but it was cutting in and out, the volume was just dropping away then coming back. Im hoping its not the amp because when i cut the pedal board out and went direct into the amp, the volume was there , much louder even on clean.

Usually, volume changes are due to power tubes showing their age because of their inability to maintain a constant bias. Another sign of bad power valves is a loss of bass and a loss of high-frequency detail.

Pedals are either "straight in and straight out" when the pedal is not engaged or the signal is buffered when off. You're most definitely going to get signal degradation when pedals are in the loop and either buffered when off (not true bypass), or turned on. You'll also get some degradation when the pedals are on, or when the pedal is off but buffers the bypassed signal. If for some reason you had the pedal without power in the on position, no signal would pass without power being supplied accordingly. Likewise, if the pedal buffered your sound when it was off and it was unplugged, you'd also not hear anything at all.

Another plausible issue is a varying wall voltage. You could try plugging the amplifier into a different circuit breaker and see if the problem still exists after the amplifier has had enough time to cool off**. If that fixes the problem - consider investing into a voltage regulator, not to be confused with a power conditioner.





**Moving an amplifier with hot tubes will necessitate heater filament damage, causing tubes to go microphonic. That means an AC small signal going into a tube modulates the loose winding, causing an uncontrolled feedback effect to be amplified - usually heard as a high pitched squeal.

This really sounds like a cord or a patch cable issue and not an amp issue. Also check your input/output jacks to make sure there tight. Easy way is to have someone move the cords around while you play. Also take a small wrench and just turn the tightening screws allittle bit on the amp jacks just to make sure there not lose

Bad tube.