In an endless endeavor to make our live show seamless, Science and myself have been experimenting for years. We have tried using external sequencers (two Akai MPC3000 drum machines). We have tried a “Master” + “Slave” system using two laptops. We have consolidated the entire live DAW into one computer. We have nearly exhausted option after option. Our last gig exposed a critical error using one computer which we were barely able to avert by discovering a fatal file. Long story short, one of our files was corrupt and would crash Logic, which we use as our DAW for live performances.
Science began researching redundant systems, which has become a norm for BIG acts. If one computer fails, another computer takes over allowing for a seamless switch to the secondary machine. This sounds simple enough, but the system required to run it was way out of our budget, AND since we use so many controllers, we would need to find a USB switcher that would baffle even the most extreme computer geek. That aside, this system only works by MIRRORING two computers. When SVN performs, our 2 Mac Pros are in independent states and thus unmirrored. WRONG SOLUTION.
But where there is a will there is a way, and we thought we would share our discovery. (FOREWARNING: there is a lot of tech-geek-speak to follow. If you are bored, we understand. Its like hearing Klingon, being translated by a Zulu shaman.)
We decided redundancy was not the way to go. Parallel systems was a good avenue, but we needed to turn TWO computers into “slaves”, and find a source of clock to constantly keep them in time with each other. If one *crashed*, the other computer would still be able to perform as normal. We decided to bring out our “studio” Mac Pro into the live arena. Yes, thats right, it takes TWO Mac Pros to get SVN to run safe and sound.
Science discovered that using a MOTU Midi Timepiece AV as a MIDI Time Code (MTC) “Master” USB’d to a start/stop trigger (like a transport on a keyboard or a third computer), we could have MTC transmitted to each computer endlessly. We connected two firewire Audio cards with installed MIDI ports to our respective Mac Pros via MIDI Inputs on our sound cards and cabled the audio interfaces to the MIDI Output ports of our MTP AV. If one computer crashed, the other kept time. Upon the return of the crashed computer, and with a simple “sample delay” over the master output of Logic, a manual adjustment would “sync” us together again. Theoretically it all made since. We went to work using a third computer to act as a trigger of Clockworks.
Almost immediately, we were able to trigger each computer DAW simultaneously. But they were both locked at at a -8 bar feedback loop in our transport. We had encountered this before years ago, and immediately addressed and synchronized frame rate speed. Still the -8 bar loop existed. We double checked that all systems were at identical sample rates. Still nothing .. . .
until we decided to do a SMPTE offset . . .
And PRESTO! we got it working, unbelievably so. SMPTE offset is something we have tinkered with before, but considering we don’t use Logic for Video work usually, SMPTE was not deemed necessary or immediately obvious. Still, it became necessary to further investigate when we learned that the MTP AV (MOTU’s MIDI Time Piece AV) converts SMPTE into MIDI Time Code (MTC).
No latency on the resync, no weird sounds when one DAW failed, nothing but a beautiful solo session by Nature or Science. When the second Mac came back online after a simulated “crash”, it picked up the MTC address and got us back in sync.
We hope this helps other people. We looked high and low on the intrawebs for similar situations other people might have. Is our system so unique? We don’t think so, but maybe it is, and that is part of what makes Science Vs Nature the beast that it is.