Hey, so my Orange TH30 head is being weird.

I keep getting this very prominent fizz through the clean channel, but just the clean channel, when i run my board into the amp.

It's not there if i go guitar straight into the amp, only with the board and only on the clean channel - a bit of hiss on the dirty but nothing out of the ordinary.

I can't work out if its a tube issue, or if its the PSU i run my pedals with.

Set up..

Fender Tele >

Crybaby, Polytune, CS-3, Box of Rock, NS-2, Small Clone, Memory Toy, Ditto >

(in the loop - Vox Delay lab, Holy Grail Plus) >


The pedals are power by a Gator G-Bus- 8, except for the Small Clone (battery) and the Delay Lab (own psu)
Any ideas? Thanks x
the fact that the issue is only present when your pedals are used would indicate it is a pedal issue, not a tube issue.

It could be the power supply or just a pedal that isn't getting along in your setup. First try hooking up your pedals and then removing one pedal at a time, or start with one pedal and add pedals one at a time to see when the the fizz comes in. Once you have identified the pedal that is causing the issue see if that pedal alone causes the same problem or only when it is in the chain.

Also try the offending pedal (or pedals there may be more than one causing an issue) with your PSU and with a dedicated power supply (wall-wart) or batteries to see if the problem persists.

That should get you started, if you can identify the pedal and what conditions cause the problem we can suggest some solutions.
it could be a preamp tube though. do the pencil test. takes less than a minute and will partially remove one variable.

what happens if you just run the pedals in the loop? what happens if you just run the pedals out front?

try a new power supply, or add one pedal at a time until you find one causing problems.