Re: [linux-audio-dev] MIDI sync issues; mmc, mtc, ...

[Paul Barton-Davis]

>In my case, I'm trying to start two complitely separate devices at exactly 
>the same time, and hope that they run at a constant speed. But, I admit,
>there's lots of things that can go wrong.
 
   [ ... ]

>And selecting among the various sync mechanisms is another difficult
>issue. Plain midi clock has little meaning for a digital audio
>recorder/mixer (concept of tempo unknown). Mtc and smpte are very good for
>doing precise location searches, but are they good enough for actually
>syncing audio apps to hardware devices or to other apps...?

you need two kinds of sync:

    1) SMPTE/MTC for location searching and general "wall clock" sync
    2) word clock for ensuring that the sample clocks run at the 
        same speed.

with both of these in place, i think things work very well.

--p