Controlling Mixer channels via midi

treading wrote:
Is it possible to send a midi message to the mixer when stopping Logic to turn the talkback channel back on between takes ?

You need to create a midi split using hardware midi routings or Logic and IAC bus to make a trick which will use same CC# to Play/Stop Logic as a keycommand and in the same time to send that message to the outboard mixer.
I just exported a short non-voice over video - get it from the link below.
Cause Logic filters all CC# messages which are assigned as keycommands I created extra routings in the Click&Ports (See the pic) so the real message will come into the Logic environment from the external controller after that it will pass thru the IAC as a "dummy" port. I use the virtual button (which matches my external controller button CC12 assignment) just for the Keycommand assignment so Logic will think that IAC is the Physical Controller and will filter the copied message which will control Stop/Play, while the original will pass thru the Instrument object (To Mixer) and control your monitoring system. I have packed the Logic template with the demo video.
You can patch a transformer between the "Split Monitor" and the "Midi Out-Mixer" Instrument port which can filter all non-matching midi events i.e only CC12 will pass to your mixer etc.

Demo Video - [DOWNLOAD|http://audiogrocery.com/files/cc_split.zip]

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treading wrote:
Using this method do I assume that I need to use an external midi device to start and stop logic ?

Yes definitely! Originally I thought you have one and use it to start/stop Loogic.
If you do not have an external controller then you can use the "Virtual Button" we used as a "dummy" Keycommand assigner ( I should let you know to delete it after the "dummy" assign), but if you do not own an external midi controller you can use it. Just patch a second cable from it to the bottom Instrument object (To Mixer). You can move the Virtual button to the top left corner of the Click & Ports Environment layer and right(control) click and make this window "Frameless" float one. Resize the float window so you can see only the button an save this as a Screenset and lock it. Hope see what I mean...
Regards

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treading wrote:
What I was hoping for was for some way for logic to generate another CC#24 midi event as I press the space bar to stop the transport.

There is no way to generate another CC#24 midi event when you press the space bar to stop the transport, cause the space bar is a computer keycommand. In my first post I gave you an idea to learn a keycommand to a given CC# (I hoped you have an external controller). OK you do not have, so you can try my second post method using the "Virtual Button" instead of spacebar. In addition, re-read my second post about cabling and select the Virtual Button and change its "Output definition" from CC12 to CC24 in the template I provided or in you project.

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