My question is twofold, how much midi jitter is acceptable? Right now I have Ableton slaved to AK midi through the USB port. Ableton’s tempo is constantly moving up to .7 at a time up or down.
If that’s too much what can I do besides buying external gear?
Not sure it’s a quantifiable number, but for what it’s worth I’ve found Elektron-elektron gear jitters by .3bpm +/-
Options are, get a dedicated midi box, or make sure all drivers are up to date
Or the other one is to get a sync box, which all but one are really expensive. I might have something to remedy this, but shhhhhh it’s a secret! 
I’m going to repeat myself:
DO NOT EVER THAT MEANS NEVER slave Ableton Live to an external MIDI clock source. If you want to include Ableton Live in your setup, you will ALWAYS have better results when using Ableton Live as the master MIDI clock source.
The reason for this has to do with Ableton’s internal architecture. It is true that Ableton Live does not provide the most tight MIDI clock ever, but IF YOU INCLUDE IT IN YOUR SETUP YOU WILL STILL HAVE BETTER RESULTS OVERALL BY MAKING IT YOUR CLOCK MASTER.
Using a good MIDI interface with good drivers, or switching to OS X might help.
I only found the Ableton jitter annoying when Ableton was a slave. It made the fx go nuts.
When Ableton is the master, tempo based fx in OT don’t jitter.
Agreed the DAW should be the master.
But this goes for any DAW not just Ableton.
…the more i think about it, the more i’m closer to go back to an hardware only setup where the computer is just a ‘recorder’. ableton live (as per mainly all the DAW out there i believe) will jitter when slaved to a piece of hardware and it’s not only because of live’s architecture but mainly because the clock message sent from whichever piece of hardware will have to travel from one end to the other. then, the other end (the pc) will need to compute the information and ‘react’ accordingly (whilst doing other tasks obviously). this requires a bit of time, therefore the jitter. i use live as master and i can pretty much live with its jittering issue but i’m more and more thinking of just an hardware setup where the software just does ‘the extra bit’ (effects, eq, stuff which would require a lot of money to get in its physical form) …
Well there a lot of different opinions in here, as I wholeheartedly disagree with this. :]
In all my years of doing this, the best results I’ve always gotten have been from matching the tempo on my external gear, matching it with the DAW, and then syncing them manually…this usually involves a few bars pre-roll and a trained response to the particular instruments’ start button.
In all honesty, if this doesn’t work, then one of your clocks is already not reliable (I have found most things are very internally accurate).
It is worth reading up on this fundamental phenomenon, as it is not as easy a problem to solve as the marketing might lead one to believe.
To answer the OP’s question, I couldn’t give you a number, but I wouldn’t say its the amount of jitter that matters - if it swings back and forth it kind of averages out - its the inconsistent nature of computer jitter that kills it for me.
Of course, the other option is for y’all to use renoise 1024 PPQN! 
Well there a lot of different opinions in here, as I wholeheartedly disagree with this. :]
In all my years of doing this, the best results I’ve always gotten have been from matching the tempo on my external gear, matching it with the DAW, and then syncing them manually…this usually involves a few bars pre-roll and a trained response to the particular instruments’ start button.
In all honesty, if this doesn’t work, then one of your clocks is already not reliable (I have found most things are very internally accurate).
It is worth reading up on this fundamental phenomenon, as it is not as easy a problem to solve as the marketing might lead one to believe.
To answer the OP’s question, I couldn’t give you a number, but I wouldn’t say its the amount of jitter that matters - if it swings back and forth it kind of averages out - its the inconsistent nature of computer jitter that kills it for me.[/quote]
My statement was in regards to syncing using MIDI Clock. 
That’s what I’m talking about.
I always have better luck not even bothering with midi clock between daw and gear - i just set them both and then ‘sync’ them by hand / rhythm.
Curious what you thought I was talking about now… ;]
Apples and oranges I suppose.
I was merely saying if you are going to use MIDI clock then the DAW should be master.
You are choosing not to use clock and just start them manually with the same tempo. Nothing wrong with that but we are talking about two different things.
Cheers
DAW on master, feed hw with clock from MIDIOX (never enough love from this amazing work Jamie O’Connell), filter DAW transport control. almost no jitter on clock with no use of timing hw.
Use Ableton Live as master with an Expert Sleepers MIDI-Interface attached to your soundcard and you’ll get a extremly solid MIDI-Clock.
our using Expert Sleepers Usamo with Line out from your soundcard. Rocksolid and cheap solution to solve midi jitter probs. Just make sure to not run more then 3 machines in a row. Better get a midi splitter by kenton or erica synths if you have more machines.