[LAD] embedded high end audio

Paul Davis paul at linuxaudiosystems.com
Sat Aug 2 16:38:44 UTC 2008


On Sat, 2008-08-02 at 13:47 +0200, Pieter Palmers wrote:
> Fons Adriaensen wrote:
> > 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.
> 
> Now that is a clever solution! Simple and elegant...

and the basis of Steinberg's VSTLink, btw ....
except that they did it by stealing a couple of bits from the sample
bitstream, and distributing the signal. 





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