Duplicate "on" messages sent in expression map

Dorico
1

Here’s my situation. I’m orchestrating a show that uses a MainStage rig. I created a playback technique called “next patch”, associated a graphic with it, and created an associated entry in the expression map. It’s a “direction” technique, since the next patch symbol will often appear in a bar full of rests. The expression map has an “on” entry to send CC 87 with a value of 127, then an “off” entry to send CC87 with a value of 0. (I’ve configured the MainStage rig to advance patches when it sees CC87)

All seems to work, except I will get a duplicate CC87-127 message when the first note of the next passage (after a bar of rests) is played. I see this in MIDIView

Controller 87: 127

Controller 87: 0

Controller 87: 127

I don’t understand why this is happening. (Also, just FYI, if I remove the “off” message I still get the duplicate “on” message, so that doesn’t seem to be a factor).

--Neil

2

Okay, I think I see what’s happening. The “on” value seems to be resent after a rest. I get why that would make sense. So I guess my question now would be, how do I create a “one shot” MIDI message? Something that can be attached anywhere in a bar, regardless of whether notes are present?

--Neil

3

Are your “on” and “off” techniques in an exclusion group?

4

No. I don’t understand how exclusion groups work, and based on my vague understanding of how they are used, how they would resolve this problem.

--Neil