Re: [Ekiga-list] Bad frequency response with Ekiga

[geo cherchetout <geo cherchetout laposte net>]

*fred k* wrote:
> > Using Ekiga v.3.9.90 ... You can see it here: http://pix.toile-libre.org/?img=1367698438.png
>
> My observation:
>
> When you (or Ekiga, or the sound card) took samples at 8 kHz and transmit two-sample running average(*) off 
> the stream, you'll get
>   0.7 dB down at 1 kHz
>   3.0 dB down at 2 kHz
>   8.3 dB down at 3 kHz
> 12.6 dB down at 3.4kHz
>
> Fairly close to 1367698438.png but not exact.

Attractive hypothesis! Only developpers know if samples are averaged this way.

> (*) a+b, b+c, c+d, ... where samples are a,b,c,d,...
>
> Another possibility is down-sampling from 44.1kHz sound card but I have no idea how it works.

The "white noise" whas generated at 8000 samples per second in the same way 
during the two conversations.