mtc

[danielmeakin]

hi Mike,

i've got a show coming up that requires 8 channels of playback, but as i'm a paranoid type who has to ensure faultless operation every night for 3 months, i'm not keen on entrusting the playback solely to a PC. I love SCS, and am going to design the entire show on it, but i need some sort of backup that will run in sync in case the PC goes south. The whole gig is run off a pair of generators, so there is always the opportunity for the power to go down at the obvious critical point in the show. i am gonna use a UPS, but that only gives me an opportunity to shut the pc down ok, restarting the show once power is restored would require booting up and waste time while i have the client watching.... plus i just don't trust my livelihood to PC's!

So, for backup purposes, i'm looking at either an 8 channel ADAT or a 24 channel HDD.

i would, however, love to be able to get the ADAT etc to effectively mirror the playback from SCS, so effectively the ADAT machine is chasing timecode generated by the PC. this would enable me to switch to the adat playback seamlessy in case of a pc failure (if i set it up to continue playback unless it gets a new midi time code message)

i understand that SCS can generate Midi messages, but i'm limited in my understanding of this. Are there MIDI commands that SCS can generate to control an external playback device like an ADAT? if not, perhaps slaving both SCS and the ADAT to a hardware midi timecode generator?

is it perhaps possible to have a midi time code cue that can run in the background, almost like a master time code as part of the editor setup, and if so would it be possible to assign it to a separate midi output?

i need to keep this as simple as possible, so if you have any ideas please let me know!

Cheers

Daniel

[Mike Daniell]

Dan,

Do you have a particular ADAT or HDD device in mind? If I can download the reference manuals for these devices I should be able to advise on how to set up appropriate MIDI Send cues in SCS.

MIDI Time Code is not yet supported in SCS. However, you could have some external device send MIDI messages to both SCS and your ADAT/HDD device - possibly sending duplicate messages on different MIDI channels so SCS will listen to one channel and the ADAT/HDD will listen to a different channel. (By 'channel' I'm referring to the channel numbers used in Note On/Off and Program/Control Change messages. In MSC a unique Device ID provides the same separation.)

Another option is to have a second PC running SCS. I presume you are planning to run the PC from one generator and the backup device from the other generator. But I guess that won't help if your sound system's generator fails.

See also Nick's reply to the posting Playback Redundancy.

[Nick]

Daniel,

The way I'd suggest is to set up your multitrack playback device to accept Midi Machine Control or MSC Locates. Each backup version is recorded one after the other, (simply playing it out of SCS into the recorder, usually) and SCS uses a Midi subcue to send Locate & Play commands to fire the appropriate backup track to match the SCS cue or sequence of cues. Thus you can jump around in the SCS cuelist and the Multitrack will be playing the right cue as well. Of course this only really works in a non-linear fashion if it is a Digital Multitrack like a Tascam MX2424 or Mackie HDR24 - an ADAT will try and keep up but will probably still be spooling tape when shorter cues are done.

Depending on the purpose of the tracks, you may want it to locate to the top of a backup but not actually play it, allowing you to restart a stalled track from the top using the backup.

cheers,
nick