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MIDI clock sync drifts over long performances

Posted: Thu Jan 05, 2006 4:09 am
by _vrsn
hey there,

a question for those using two laptops in a performance situation: i am finding that the sync between our two ibooks will drift during performances over 30min causing the dreaded flanging beats. we've been correcting it by stopping the master machine for a second and hitting play again, but obviously this is a tough thing to cover up with continuous mixes. our 2hr new years performance required three stop/starts.

both ibooks are at around 50-60% cpu with maxed out ram and sync'd over an ethernet cable. it's otherwise a solid rig, but the drift is a pain. any solutions, or at best, tips on re-synching that doesn't require stopping playback?

thanks, vrsn.

Posted: Thu Jan 05, 2006 11:44 am
by justin
hmm not sure about sync over ethernet. i've not had the chance to use it yet.
do u get the same thing if u use a MIDI clock? that's the way i have done it in the past (it was fine for me in Live 4, havent checked with v5).

this might be a bit OT, but i dont really get this trend for ethernet sync in nu apps.

my own experience of making music with computers tells me that u should leave it to focus on running the application. MIDI works fine and although it requires a driver to run the box, i think it should be lighter on CPU and tighter timing than using ethernet.

i dunno, it seems the ethernet port should achieve the same as a MIDI box (hell it might even clock at a higher speed). but it is an intrinsic part of the OS, and the question is: can it operate without interruptions by various OS related network activities :?:

At least i know that with a MIDI box my CPU is not trying to scan for printers or other networks (maybe that is what is happening in ur setup)...

Just a few thoughts. pls, feel free to correct me on this!

Posted: Fri Jan 06, 2006 8:58 pm
by roby
off topic, I know..but I always though that heavy SysEx transmission would have better performance through ethernet...

Re: MIDI clock sync drifts over long performances

Posted: Fri Jan 06, 2006 9:09 pm
by Machinate
_vrsn wrote:tips on re-synching that doesn't require stopping playback?

thanks, vrsn.
that would be switching the Midi CLock Mode from Song to Pattern in the midi/sync preferences. This way Live sends the start message every bar.

Does that help?

Posted: Sat Jan 07, 2006 6:18 pm
by _vrsn
hmmm...i was not aware of the different modes for midi clock. i'll give it a try...thanks!

for an external midi clock source, has anyone seen a particularily small unit? we're not into lugging around rack gear or external drum machines. it would be nice to have something the size of the alesis nanoverb.

Posted: Mon Feb 06, 2006 12:25 pm
by bland_handl
that would be switching the Midi CLock Mode from Song to Pattern in the midi/sync preferences. This way Live sends the start message every bar.
Hey Machinate, you're the first person I've come accross with a solution to this one, but I can't find the Clock Mode option you mentioned... is there someting I'm missing?

PS - the only technique I've come up with so far is to set up a midi clip on each laptop - a one-shot clip on the Master containing a note (say G8 on ch.16), and an empty clip on the Slave having it's Play button assigned to the same note, while routing the Midi From to the Master device (ch.16). Whenever you need to catch the sync, just fire the Master's clip and the Slave's sequencer will start up.

it does allow dropping sync and picking it back up again, but it's not clocked, and the drift gets pretty heavy after a while. And unfortunately assigning the Slave's global Play button to this midi trigger completely freaks the timing.

But if you could clue me further on your answer you'll go double-platinum on my all-time hero charts!

Posted: Mon Feb 06, 2006 1:07 pm
by hambone1
I had never-ending problems with ethernet sync (both wired and wireless).

I'm now doing it over MIDI with one MIDI port dedicated to sync only.

Works great, and doesn't drift or lose sync any more.

Posted: Mon Feb 06, 2006 3:17 pm
by Magnetotron
Hey guys,

Is it normal when using external sync that the BPM display in Live doesn't update?

1. I have EXT selected on machine one
2. Machine 2 changes the tempo
3. Machine one's metronome changes tempo but the BPM display in Live still says whatever it was before the change.

For some reason it doesn't seem right. I thought it would change along.

Posted: Mon Feb 06, 2006 4:21 pm
by hambone1
The tempo should change. Sometimes it takes a second or two to settle, especially on larger tempo changes.

Posted: Tue Feb 07, 2006 12:49 am
by bland_handl
I've been noticing a fair bit of buggy behaviour with ethernet as well but am fairly new to it, so it may be just me....

But with your set-up Hambone, are you able to drop sync and re-sync at will?

Posted: Tue Feb 14, 2006 1:19 am
by leandro
bland_handl wrote:
that would be switching the Midi CLock Mode from Song to Pattern in the midi/sync preferences. This way Live sends the start message every bar.
Hey Machinate, you're the first person I've come accross with a solution to this one, but I can't find the Clock Mode option you mentioned... is there someting I'm missing?
that option is in the midi out prefferences (not in the midi input).. so u shuold change that on the laptop that will be the midi master (not the slave one)

i will give that a try also and see how it works

Posted: Tue Feb 14, 2006 1:38 am
by bland_handl
Hey there Leandro

I've looked everywhere in the midi/sync preferences pane, but I still can't find any Song or Pattern options there...

is it possible you could provide a screenshot?

(I'm on Live 5.01 on a mac, maybe that changes things??)

thanks

Posted: Tue Feb 14, 2006 2:52 am
by husker
Yip...Song/Pattern mode came in with 5.02

It also has better midi sync in general, so should help your problem

cheers.

Posted: Tue Feb 14, 2006 6:35 am
by bland_handl
(hand slapping own forehead)

thanks husker, (and machinate and leandro!).

you've totally just made my day/week/live-set!!!

guess the old "if it ain't broke" philosophy doesn't always fit.

:)

Re: MIDI clock sync drifts over long performances

Posted: Fri May 05, 2006 12:02 am
by Groovecake
Machinate wrote:
_vrsn wrote:tips on re-synching that doesn't require stopping playback?

thanks, vrsn.
that would be switching the Midi CLock Mode from Song to Pattern in the midi/sync preferences. This way Live sends the start message every bar.

Does that help?

I don't see anything about that in the manual. I haven't had a chance to try it. Would this enable a slave that has lost sync for one reason or another get back in sync without a start/stop from the master?