Joe Bell

Hello forum members, I'm newly registered and am a musician/sound artist/recordist practicing round London. I'm trying to understand how to correctly format a MIDI message for a lighting controller.

I've got a variable voltage regulator controlling some sound synthesis, and I want it to culminate with a spasmodic dimming of the stage lights. I thought the best way to do this would be to send some messages to the Grand Master Fade.

Trouble is that I'm not getting to grips with how to compose this MIDI message, and how to wield it in max. I have researched the subject and related concepts, I just cant get my head round it.

http://img210.imageshack.us/img210/1441/snapshot20080322012232xi0.png

If someone could tell me a good way to send a fixed message to this particular controller that would be very helpful! Then I can reverse engineer it and I'll be a happy man for my show starting next tuesday

I've got a variable voltage regulator controlling some sound synthesis, and I want it to culminate with a spasmodic dimming of the stage lights. I thought the best way to do this would be to send some messages to the Grand Master Fade. 

fairly-basic-midi-question-trying-to-understand-1991-light-desk-manual

It looks like the "Grand Master Fader" requires a continuous controller 13 message.

The MIDI bytes are listed there in the manual as hexadecimal (base 16) numbers.

Bn means "continuous controller number on channel n". B is equivalent to decimal 11 in the 16s column, which would be 176 (11x16). n is the channel number on which your device is receiving (from 0 to 15, the way the computer understands it, rather than from 1 to 16 the way humans talk about it) So, for example, if your device is set to receive on MIDI channel 1, you would add 0 to 176 and get 176. (For MIDI channel 2 you would add 1 to 176 and get 177, etc.)

The next number is the continuous controller number for addressing the grand master fader. It's hexadecimal 0D, which is equivalent to decimal 13.

The next number is anything from 0 to 127 that specifies the fader's virtual position. Presumably 127 means fader fully up, and 0 means fader fully down.

So (assuming for the sake of this example that your device is set to receive on MIDI channel 1) to control the grand master fader, send the message "176 13 127" to a 'midiout' object to turn the fader up to full. Another way to do this would be to use a 'ctlout' object, send the number 1 in the right inlet, the number 13 in the middle inlet, and then send 127 in the left inlet.

To create a continuous fade, send successive messages with gradually changing fader position values.

For most of the other faders, it looks like you need to send *two* continuous controller messages to set a fader position. So, for example, to control the "A Crossfader", first send it "Bn 0C 10" (hexadecimal), which is to say "176 12 16" (decimal), then send it "Bn 10 vv" which is to say "176 16 127" (or whatever fader value you desire). Get it?

Here's a little patch that demonstrates. Hope it helps. (Double-click on the midiout or ctlout object and make sure that it's addressing the correct device, then set the correct MIDI channel, then move the fader.)

thanks so much for your help man - now you have given me the answer I see what a buffoon like question is was, your patience is appreciated. I was in the theatre space today having some fun!

fairly basic MIDI question... (trying to understand 1991 light desk manual)