HOWTO: Sync two computers running Ableton Live via network

[dotpim]

1. Introduction

I always really wanted to be able to have two PC's running Ableton Live in perfect sync, and never found a good tutorial or actually working and stable solution.
By combining knowledge from a lot of posts on a lot of forums and experiencing lots of frustration doing so, I finally got it. In this post I will try to share how
to set this up.

If you want to be able to change bpm while you are playing, this tutorial is not for you.



2. Required software

Windows XP - Because the version of MIDIoverLANPlus I used only runs on XP, newer versions of this software should run without problems on newer Windows versions and even on mac.

Ableton Live - Tested and working on versions 7 and 8.

Musiclab MIDIoverLANPlus 1.1.112 - This tool is used to transfer the midi signal over the network, and provide a local virtual midi port for the computer running the clock.
Newer versions work as well, but setting them up is a bit different but. It's a shame I couldn't find a free solution instead of Musiclabs software. They have fully functional 30 day trials though.
The freeware ethernetmidi tool does not work, even though it gets mentioned a lot in threads about midisyncing over lan.
Update: I found a free tool that promises to provide the same functionality as MIDIoverLANPlus. Will test and post results.Wac.NetworkMIDI (v1.2)


MIDI-OX - This tool is used to send a midi-timecode (mtc) signal to both computers. Freely available at: http://www.midiox.com/moxdown.htm



3. Configuring MIDIoverLANPlus

Install this software on both computers, reboot them both. Then start the configuration utility from the windows control panel. One computer will send the midi signal (pc1) and one will be receiving a midi signal (pc2).
On pc1, setup at least one local pipe (this is used to send the mtc from MIDI-OX to Live) and at least one MIDI to LAN port. You can leave the buffer and port settings at defaults.
On pc2, setup at least one MIDI from LAN port. Make sure you use the same port as on pc1.
Apply the settings and close the configuration utility.



4. Configuring MIDI-OX

Install this software on pc1 only. Via Options>MIDI devices add the needed MIDI outputs. I used LAN-Out 00 and Pipe-Out 00.



5. Configuring Ableton Live

Make sure the MIDIoverLANPlus configuration utility is running before Live is started, otherwise Live may not recognize the ports you need to configure. This took me forever to find out.
Open the midi settings via Options>Preferences>MIDI Sync.
On pc1, enable sync for Pipe-In 0, track and remote functions should be disabled.
On pc2, enable sync for LAN-In 00, track and remote functions should be disabled.
On both computers set sync type to MIDI Timecode, set MTC Frame Rate at 30 fps. MIDI Clock Sync Delay should be on 0 ms for now, this will be adjusted later.
Close Ableton Live on both computers.



6. Configuring local network

I had the best results using a crossover lan cable between both computers. This provides you with <1 ms network latency. Setup manual IP's on both pc's, for example 192.168.100.100 and 192.168.100.101, subnetmask 255.255.255.0
Being connected to a wireless network at the same time resulted in MIDIoverLANPlus not functioning anymore, so just turn it off.
Firewalls should be disabled (since you are working on a local network it probably won't hurt you), or at least make exceptions on both computers for the port MIDIoverLANPlus needs.



7. Actual usage instructions

After setting up the things mentioned above, reboot both computers to be sure MIDIoverLANPlus driver is loaded correctly with the new settings (yes, I do like to reboot when doing things like this).
Now, on pc1 one start the MIDIoverLANPlus configuration utility, and just leave it open. Also start MIDI-OX.
On pc2 also start the MIDIoverLANPlus configuration utility.
In MIDI-OX open View/Generate MIDI Time Code, set it at 30 fps with accuracy set to 5 ms. Start the clock before starting Live.
Open Live on both computers now. Click the EXT button in the upper left corner on both computers. You should now be receiving a time code signal.
This signal runs at fixed bpm, the trick to get it working at your desired bpm value is having the clock running before starting Ableton Live, then enable external sync on both computers (as mentioned above).
Now stop the clock in MIDI-OX, but leave the program open. Set bpm at the right value on both computers and start the clock in MIDI-OX again. Both computers should now be receiving time code and play at the correct bpm.
Any mixer can be used to combine the audio signals from pc1 and pc2, I used a third computer for it. Find a solution that works for you.
It's time to get things running in sync now. This involves a bit of playing with latency values. First I made sure that the various latency related settings for the sound cards on pc1 and pc2 were set identical.
On pc2, leave the MIDI Clock Sync Delay at 0 ms. Get a metronome playing on both computers. Adjust MIDI Clock Sync Delay on pc1 until both metronomes are playing in sync, for me 24,5 ms works perfect.

That's it. I tested this on multiple setups and it just works. Here's a 4 hour proof of concept mix, stayed in sync until the end:

[mmauve]

Quick, someone get this guy a medal and a mug of the finest ale.

This post kicks ass.

[irritaSies]

[tekki]

Nice 1 dotpim!

[bgardali]

I didn't realize how spoiled I was doing this with two macs...

1. Connect crossover cable.
2. Open Audio Midi Setup.
3. Start new session, connect to other computer.
4. Send midi clock in Ableton on 1st computer.
5. Receive midi clock in Ableton on 2nd computer
6. Computer 1 can manipulate BPM to hearts content.

[dotpim]

4. Send midi clock in Ableton on 1st computer.
5. Receive midi clock in Ableton on 2nd computer

This can be done on PC too (again, using MIDIoverLANPlus), but the slaved Live always drifts out of sync. Is this method really stable on mac?

[bgardali]

It's not perfect but it gets the job done. On the slave computer it appears as if the BPM is always adjusting but the results are smooth. The way my DJ partner and I use the sync you would never notice (we pass control back and forth every few songs) but if you were attempting to do something more integrated like one computer running drums and bass and the other running melodies/vox, etc you might run into some noticeable issues.

[dotpim]

Sounds like you suffer from the same instabilities as I had on windows. Maybe you could archieve (almost) perfect sync using reaper as mtc source for both computers running ableton with something like this: http://forum.cockos.com/showthread.php?t=43606

[Weezi]

This is amazing

is there an issue with the midi delay between both computers, I could see the buffer creating a slight delay when triggering tracks over the network? Considering you were sending information through cross over cables would be the only issue I could see coming up.

[dotpim]

Not really, when midi latencies are set properly both computers are completely in sync. Audio gets sent out using the same asio buffer sizes so both signals should reach the mixer without noticable delay.