Just out of interest Will, I've already tried 2 separate power supply plugs into my keyboard, and I still get an annoying noise when plugging them into an amp/line in on my PC soundcard. The keyboard has onboard speakers, but I can't detect any annoying noise when the keyboard volume is up full, with my ear against the speaker...<br>
<br>This might be a problem with my sockets and/or my keyboard line outs being futzed?<br><br>Thanks,<br><br>Andrew.<br><br><div class="gmail_quote">On Mon, Nov 30, 2009 at 7:15 AM, Will Light <span dir="ltr"><<a href="mailto:visinin@gmail.com">visinin@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">but I've had issues with<br>
noises like the one you posted that stemmed from, of all things, the<br>
power supply being grounded.<br>
<font color="#888888"><br>
-w<br>
</font><div><div></div><div class="h5"><br>
On Sun, Nov 29, 2009 at 2:10 PM, Andrew C <<a href="mailto:countfuzzball@gmail.com">countfuzzball@gmail.com</a>> wrote:<br>
> Hey Rich,<br>
><br>
> Yeah, I plugged both keyboard and amp into different outlets, and I got the<br>
> same noise. :/<br>
><br>
> Will, I'll test that out tommorrow, when I get a 9 volt battery or two.<br>
><br>
> Also, just for the hell of it, I'll get a DI box anyway, just to see if it<br>
> does anything for it.<br>
><br>
> Andrew.<br>
><br>
> On Sun, Nov 29, 2009 at 6:31 PM, Ricardus Vincente <<a href="mailto:wizardofgosz@gmail.com">wizardofgosz@gmail.com</a>><br>
> wrote:<br>
>><br>
>> On Sun, 2009-11-29 at 18:44 +0100, <a href="mailto:fons@kokkinizita.net">fons@kokkinizita.net</a> wrote:<br>
>><br>
>> Are you plugging the devices into different outlets?<br>
>><br>
>> Rich...<br>
>><br>
>><br>
>> > > How can I check if the keyboard/power supply is grounded? The power<br>
>> > > supply<br>
>> > > itself is a three pronged one....<br>
>> ><br>
>> > Then in most countries it is required by law to be<br>
>> > effectively grounded. Next question is if you power<br>
>> > socket is... It should be if it accepts the plug.<br>
>> ><br>
>> > Since you also have this interference with an amp,<br>
>> > but not with the headphones it really seems to be<br>
>> > a grounding problem.<br>
>> ><br>
>> > To only other way to explain it would be to assume<br>
>> > it's some high-frequency stuff which your headphones<br>
>> > would just ignore, but any active input such the amp<br>
>> > or soundcard could demodulate into the audio band.<br>
>> ><br>
>> > If you're using a laptop, does running it on battery<br>
>> > make a difference ?<br>
>> ><br>
>> > Anyway I'd try a DI box, it's good practice anyway with<br>
>> > all instruments.<br>
>> ><br>
>> > Ciao,<br>
>> ><br>
>><br>
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</div></div></blockquote></div><br>