MIDI sync weirdness

[pulse]

dont know if it helps
but here is my little exp:
- I use midi sync out to sync external synths (to run sequences inside the synth)

I had timing problems by default.

here are the two things that made it work:

1) in the midi panel of OSX, choose the audio interface as a source of timing, not the internal one (with the internal it was always not in time)

2)if it does not work, reboot, the second time runs always perfectly in time ...

[chaosmoon]

i tried a few things today and found the following:

Live as master is useless. Things run sync for a while if i don't touch the computer. As soon as i change program focus(finder, system prefs, whatever) sync slips. Same goes for moving sliders etc in an open max patch which i'm using for an interface via bpatcher/M4L.

However, running the Korg ER-1 as master and adjusting the midi-sync delay i was able to run rock solid for 20 minutes whilst fiddling with pretty much anything.

I wonder if this is due to the whole timestamping thing?

[3phase]

i tried a few things today and found the following:

Live as master is useless. Things run sync for a while if i don't touch the computer. As soon as i change program focus(finder, system prefs, whatever) sync slips. Same goes for moving sliders etc in an open max patch which i'm using for an interface via bpatcher/M4L.

However, running the Korg ER-1 as master and adjusting the midi-sync delay i was able to run rock solid for 20 minutes whilst fiddling with pretty much anything.

I wonder if this is due to the whole timestamping thing?

what system and Live version are you using? that sounds like a bad bug.. had issues lately aswell.. and that scares me .. because i mainly use ableton as the clock master on stage... and for a few loops from older tracks..

actually ableton live was the best program as clockmaster sofar.. much better than logic.. more options to run different timing offsets. and better start event placement..

would be a desaster if ableton would loose the superior performance at theese essentila point.. than it would be time to go 100% hardware again

[chaosmoon]

signature added.

I havn't felt the need to go beyond 10.5.5, maybe its time to clone and update.

[3phase]

you defently should check with the latest version of live..

do the pro applikation updates from apple..they seem to help the midi situation a lot.. at least i had the impression in the past that they shift some internal priority to the core audio midi engine..

ther was also a new mt 4 driver not so long ago...

[chaosmoon]

Today i made a midi-audio cable and recorded some midi clock streams.

Live aint to good, with a variation up to 2ms per tick.
My GenoQs Nemo was pretty damn solid and i've decided to use it as master-clock.

If Live(8.1.3) is master i can fiddle around, change program focus and all is well.

If Live is master and Max is running things will sometimes slip.

Nemo as master, Live and a Korg ER-1 slaved and i can open and scrub through quicktime movies in the background, mess with the laptop hardware like bluetooth, create patches in max and all stays locked.

[broc]

I think that even with a perfect global Midi clock master it's still problematic to run a DAW like Live as Midi clock slave.

For example, consider a Live set with some plugins that introduce latency. This is compensated within Live by delaying other tracks accordingly. So if Live receives a start message everything will be played with the same delay.

Now lets say you want to run a drum machine as another slave in sync with Live. Obviously it must be delayed by the same amount. And this adjustment (if possible at all) must be done individually for each Live set depending on its actual delay.

Note that this problem doesn't occur with Live as master since Midi clock start can be included in delay compensation.
But I'm not sure if and how it's actually implemented.

[chaosmoon]

Good point.

I guess innerclock systems "sync-lock" is the best way to go then..

sync-lock product page

You build a sync track by placing the pulses on an audio track and sending it (audio-out) to their box. The box then generates a solid midi/trigger/din-sync output. Because its generated from an audio track, all delay compensation etc. should be taken care of.

475 euro..ouch.

[broc]

Yes, "sync-lock" seems perfect for slaving zero-latency hardware sequencers.
But it does not work if the slave has some latency (like any DAW).

[chaosmoon]

I'm more concerned with multiple machines(midi-thru after the sync-lock) with different latencies. Innerclock systems also sell a shifter, but at 475 euro's each i'm wondering if i could hack a simple midi delay with an Atmel/Arduino.

I think you could compensate for latency with a negative track delay on the pulse track in Live, no?

[luddy]

I think you could compensate for latency with a negative track delay on the pulse track in Live, no?

The MIDI sync offset stuff in Live's Preferences, in the MIDI/Sync tab, is designed for this purpose, although I don't know what if anything it does about project-specific latency. If you click on the triangle next to any of the MIDI In or MIDI Out ports, a drop-down menu appears that lets you adjust the MIDI sync offset in milliseconds.

-Luddy

[chaosmoon]

The problem is that Live's midi-clock output is unstable. Sync-lock is a hardware box that generates a midi-clock stream from a high priority audio output. The midi preferences are not used in this case.

[broc]

I'm more concerned with multiple machines(midi-thru after the sync-lock) with different latencies. Innerclock systems also sell a shifter, but at 475 euro's each i'm wondering if i could hack a simple midi delay with an Atmel/Arduino.

I think you could compensate for latency with a negative track delay on the pulse track in Live, no?

You're right, the negative track delay should work. Good idea.

Wouldn't it be possible to hack the complete audio pulse to midi clock conversion with Arduino?

[chaosmoon]

yes, but i'm not sure if i want to spend the next few months doing it...How much DIY is 500 euros worth?

[chaosmoon]

erm..I just got Live to sync to a simple arduino midi clock. Maybe i'll investigate this after all.