Re: [LAU] Realtek ALC882D - Linux-audio-user

30 Jul 2007

I have made two graphs of the hums frequency content (via some Matlab
wizardry).  The "zoomedout.jpg" shows most of the frequencies in the
signal.  The "zoomedin.jpg" shows that 60 Hz is by far the loudest
frequency.  Interpret as you please.

http://www.prism.gatech.edu/~gtg601q/LAU/zoomedout.jpg
http://www.prism.gatech.edu/~gtg601q/LAU/zoomedin.jpg

-DanielG

On 7/30/07, linux-audio-user-request(a)lists.linuxaudio.org <
linux-audio-user-request(a)lists.linuxaudio.org&gt; wrote:
...

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 I have been told that this is probably caused by the power distribution
 circuitry within the laptop: it does not separate earth ground from "signal"
 (I'm assuming USB signal since my audio interface is USB) ground. The buzz
 certainly sounds more like "computer" noise than 60 cycle hum.