9 Jun
2010
9 Jun
'10
4:31 p.m.
Excerpts from fons's message of 2010-06-08 12:08:27 +0200:
On Tue, Jun 08, 2010 at 08:53:43AM +0200, Philipp
Überbacher wrote:
I still don't understand why there's such a high amplitude spike each
2kHz. But don't worry, I will eventually :)
--
Regards,
Philipp
--
"Wir stehen selbst enttäuscht und sehn betroffen / Den Vorhang zu und alle Fragen
offen." Bertolt Brecht, Der gute Mensch von Sezuan
So the actual problem isn't the noise but its
correlation with the signal?
Yes.
I'm a bit curious about the first graph. The
actual signal is the ~1kHz
one, but what are all the other 'spikes'?
The quantisation error appearing as distortion. This the problem
that is solved by using dithering.
1 kHz at FS = 48 kHz means a period of exactly 48 samples, the
same values are repeated for each period. So the quantisation
error is periodic as well, with a period of 1 kHz. In other
words, distortion. Adding noise randomizes the quantisation
error.
Ciao,