On Fri, 30 Nov 2007, Sergei Steshenko wrote: > On Fri, 30 Nov 2007 12:19:55 +0100 > Paolo Saggese <pmsa4-alsa@xxxxxxxx> wrote: > > [snip] > > I am sorry, but all the above said can be summarized in very few sentences: > > 1) any phase/frequency modulation produces a signal with infinite > spectrum; If things like noise and digitization did not occur, this would be true. In real life it is not. It is not hard to make a clock good to ppm, and that is a -120dB, way below the noise floor, on a 0dB (Ie full amplitude) signal. > > 2) analog recordings additionally have jitter due to tape elasticity > and surface imperfections - has anyone ever observed analog taper recorder > signal using an oscilloscope ? - I have; Yes. > > 3) one may argue about similarities and differences of spectra produced > by analog era and digital era jitter; And what is digital jitter? Do you mean timing changes in the A-D sampling clock? > > 4) any high end digital receiver should have a PLL-based receiver that > resamples (with the same frequency) input signal end eliminates jitter > - rather, the jitter becomes the one of the PLL; No idea what this means. No resampling can get eliminate jitter already in the signal. And PPL does not mean jitter free. On the other hand it does not take much of a clock to reduce all sampling jitter way below the noise floor. > > 5) from my experience the decisive factor nowadays is analog circuitry > in the power amplifier and speakers, not digital jitter. Decisive for what? ------------------------------------------------------------------------- SF.Net email is sponsored by: The Future of Linux Business White Paper from Novell. From the desktop to the data center, Linux is going mainstream. Let it simplify your IT future. http://altfarm.mediaplex.com/ad/ck/8857-50307-18918-4 _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
