[LAD] midi beat clock

Tim E. Real termtech at rogers.com
Mon Feb 22 01:19:13 UTC 2010

On February 19, 2010 10:17:12 pm Gabriel M. Beddingfield wrote:
> As PD said, the MIDI spec requires That MIDI Clock (0xF8)
> pulses be sent out at a rate of 24 clocks per quarter note.
> Meanwhile, a MIDI Tick (0xF9) is sent out at a rate of 1
> tick per 10 ms.  The difference is whether you are syncing
> time or tempo.  Sounds like you want tempo (MIDI Clock
> 0xF8).
> There's a pretty good MIDI reference here:
>      http://www.blitter.com/~russtopia/MIDI/~jglatt/tech/midispec.htm
>      http://www.blitter.com/~russtopia/MIDI/~jglatt/
> FWIW, using MIDI clock you can effectively sync tempo.
> Synchronizing down-beats is more difficult... since there is
> never a signal that says "this clock pulse marks a beat."
> Hope this helps!
> -gabriel
Good stuff. Thanks. Had no idea that 100Hz tick was for time-based sync. 
Meaning we could use it for audio...

Interesting, MTC full frames are 12Hz (@ 24fps) and quarter frames @ 96Hz.
(Correct my rusty reviewing).

But Paul said that it can be 'quite bursty', I assume he meant the 
 quarter frames - and I think I also read one should not trust the full frame 
 to occur precisely 'where it should be'. After all, it is a sysex...

So I Wonder if 'tick' is a more stable, straight forward, and faster option
 for basic uses vs MTC at 24fps

Still curious, someone said he had this 'tick', which app sends it?

Imagine. Midi clock, active sense, tick and/or MTC all on the same line...

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