Re: [Alsa-user] Sound quality

[Andrew G. <a...@ga...>]

Fons,

Can not miss an additional opportunity to tell you:

- Thanks for the 'jaaa'!

As for non-harmonics artifacts - you are right. Rather long cable was used, ground/shields
were optimized to measure a device rather a loopback. This real device spectrum is cleaner
(-9db for 15625Hz):

http://gaydenko.com/preamp/un-4KHz-500mV.png


Andrew

======= On Tuesday 22 November 2005 02:38, you wrote: =======
On Mon, Nov 21, 2005 at 03:07:48PM -0800, Bill Unruh wrote:
> On Tue, 22 Nov 2005, Andrew Gaydenko wrote:
> 
> >As for Terratec Aureon 7.1 Space, this is own the card spectrum:
> >
> >http://gaydenko.com/preamp/card-own-4KHz-500mV.png
> >
> >Besides harmonics, you can see some PC-realated (I think) artifacts.

Interesting spectrum. The marked line at 12 Khz (and the 8 and 16 kHz lines)
are of course just harmonic distortion.

The lines at 7.5 and 15 kHz are related to the peculiar spikes that
fill most of the spectrum. This is a typical spectrum for digital
interference. 

Then there is the one between 15 and 16 kHz. That could very well
be picked up from a nearby TV set. If it's 15625 Hz or near, you
can be sure that's the source. I can verify if my neighbour is 
watching TV by just running a cable near the wall that separates
us in this way.