[LAD] embedded high end audio

Fons Adriaensen fons at kokkinizita.net
Sat Aug 2 11:07:58 UTC 2008


On Sat, Aug 02, 2008 at 01:01:12PM +0200, Pieter Palmers wrote:
> Florian Faber wrote:
> > Peter,
> > 
> >> I doubt that it is easy over a transport protocol that doesn't have a
> >> global absolute time reference (like ethernet).
> > 
> > What time reference do you have in mind on ethernet that can be used as 
> > word clock source?
> 
> My formulation is a bit unfortunate. I mean that ethernet does NOT have 
> a global absolute time reference. And word clock is not a time 
> reference. It's a 'rate' reference, which does not contain absolute time 
> information. What you need to output signals on different devices with 
> sample accurate phase is an absolute time reference. Which ethernet does 
> not have.

The solution I'm using in this case is to distribute
a single audio signal (similar to the one used in jdelay)
to all computers. The signal can be decoded into a sub-
sample accurate time, and all network data are timestamped
using this time scale.

Ciao,

-- 
FA

Laboratorio di Acustica ed Elettroacustica
Parma, Italia

O tu, che porte, correndo si ?
E guerra e morte !






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