Marshall Jubilee head crackling

[Bluefinger]

I have another problem with a Jubilee head. It is extremely sensitive to other devices connected to the same AC circuit. If it's running and I switch on a neon light in the same room it produces a loud noise from the speakers ... even if I plug in or unplug a soldering iron next to it it produces a decent pop. Other amps in the same AC circuit don't do that at all or at least at a much lower volume. Otherwise the amp is fine ... no excessive hiss or other noises. Is this a fault or just a side effect of it'S high gain design? BTW ... it happens in all three channels. All tubes have been replaced without any noticeable changes ...

thx!

[Jazz P Bass]

You could try a varistor across L1 & L2 from the mains supply.
Some amps are that way
Especially high gain amps.
As to the neon signs, I do not know anything, short of unplugging them , that will alleviate that hash on the lines.
Maybe a good PSC like a Furmann would help.
Link: http://www.radioshack.com/search/ind...=varistor&sr=1

[Bluefinger]

Thanks ... I'll give it a try

[Gtr_tech]

One word.....Isobar.
Amazon.com: Tripp Lite ISOBAR6ULTRA 6 Outlet Isobar Premium Surge Protector (3330 Joules): Electronics

Well worth the money.