[LAD] embedded high end audio

Pieter Palmers pieterp at joow.be
Sat Aug 2 11:47:46 UTC 2008


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...

Greets,

Pieter



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