Re: [LAU] open hw soundcard (was Re: status usb2 for sound)

On Fri, 13 Nov 2009 14:57:51 +0100 (CET)
karl@email-addr-hidden (Karl Hammar) wrote:

> Folderol:
> > karl@email-addr-hidden (Karl Hammar) wrote:
> ...
> > An entire cycle of 48kHz is about 20 uS so jitter would have to be
> > significantly less than that to avoid 'cogging'.
>
> So jitter < 1us would be required ?

I think it actually only needs to be less that 10uS

> What is "cogging" ?

The effect you can get with a system with poor stability but very strong
locking when incoming pulses are half way between the wanted times
(used to happen a lot with early discrete PLLs). The system will
alternately lock on the early and late pulses. The correction waveform
looks like a cog railway :)

-- 
Will J Godfrey
http://www.musically.me.uk
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.
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