[LAU] Am I experiencing ground hum or is it something else?

[Andrew C]

Hey Rich,

Yeah, I plugged both keyboard and amp into different outlets, and I got the
same noise. :/

Will, I'll test that out tommorrow, when I get a 9 volt battery or two.

Also, just for the hell of it, I'll get a DI box anyway, just to see if it
does anything for it.

Andrew.

On Sun, Nov 29, 2009 at 6:31 PM, Ricardus Vincente
<wizardofgosz at gmail.com>wrote:

> On Sun, 2009-11-29 at 18:44 +0100, fons at kokkinizita.net wrote:
>
>  Are you plugging the devices into different outlets?
>
>  Rich...
>
>
> > > How can I check if the keyboard/power supply is grounded? The power
> supply
> > > itself is a three pronged one....
> >
> > Then in most countries it is required by law to be
> > effectively grounded. Next question is if you power
> > socket is... It should be if it accepts the plug.
> >
> > Since you also have this interference with an amp,
> > but not with the headphones it really seems to be
> > a grounding problem.
> >
> > To only other way to explain it would be to assume
> > it's some high-frequency stuff which your headphones
> > would just ignore, but any active input such the amp
> > or soundcard could demodulate into the audio band.
> >
> > If you're using a laptop, does running it on battery
> > make a difference ?
> >
> > Anyway I'd try a DI box, it's good practice anyway with
> > all instruments.
> >
> > Ciao,
> >
>
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