Hoffman Amplifiers Tube Amplifier Forum

Other Stuff => Effects => Topic started by: dude on August 18, 2011, 11:53:49 am

Title: Wah-wah that hums - Ground loop?
Post by: dude on August 18, 2011, 11:53:49 am

Nothing but the Wah wah pedal and it hums, take it out go straight to amp, quite.

I read about a ground loop but don't know the fix with a pedal.

If I turn the pedal off, no hum.

Any suggestions? I did search and found the ground loop could be causing the problem.

But the fix?

thanks,

al

Title: Re: Wah-wah that hums - Ground loop?
Post by: sluckey on August 18, 2011, 12:37:51 pm

Does it hum regardless of which amp it's connected to?

Title: Re: Wah-wah that hums - Ground loop?
Post by: dude on August 18, 2011, 11:50:11 pm

Yes any amp, alone or with other pedals in a chain.

It's definitively the wah-wah pedal if I leave the wah off no hum.

I play an 18 watt Trinity SIII TMB, which plays great no hum alone or with these three pedals, strat into a Boss CS-2 compression, then Ibanez TS10 (modded to 808 specs) and sometimes an Ibanez GE10 EQ. I just started to try the wah-wah and put it first in the chain.

Just the strat and wah and it hums too, no other hum with any of the other pedals just when I add the wah in the front.

Thanks,

al

Title: Re: Wah-wah that hums - Ground loop?
Post by: VMS on August 20, 2011, 09:25:41 am

What wah-wah pedal are you using?

Is it powered with battery or a power supply?

Title: Re: Wah-wah that hums - Ground loop?
Post by: dude on August 20, 2011, 09:41:20 am

Crybaby, from the late eighties or early nineties.

Model GCB-95,  made in USA

external power supply at 9.45v dc

Thanks,

al

Title: Re: Wah-wah that hums - Ground loop?
Post by: VMS on August 20, 2011, 10:12:37 am

Try and see what happens with battery.

Title: Re: Wah-wah that hums - Ground loop?
Post by: dude on August 25, 2011, 04:26:48 pm

Sorry for the long delay getting back, I didn't have a good 9 volt and kept forgetting every time I went out.

Anyway, Bingo works great no hum at all.

So I guess I'm limited to a 9 volt for the wah?

thanks,
al

Title: Re: Wah-wah that hums - Ground loop?
Post by: sluckey on August 28, 2011, 08:52:43 pm

Maybe get a better power supply.

My old Thomas Organ Cry Baby works fine with my power supply and it was never meant to be used with anything except a battery.