Hi, I was wondering if someone knows if MIDI implementation on Octatrack can send out NRPN messages or CC only? I got DSI synth which can receive both NRPN and CC messages but so far I only managed to send CC out of Octatrack. What I am trying to do is to have different LFO speed on different trigs - synth’s LFO is clock synced to BPM so I would like to alter speed - 1.5 for one trig and 1 for other trig. LFO speed on synth can be controlled through NRPN but not CC. So I wondered if someone in forum ever come across needing NRPN from Octatrack.
It’s basically CC only.
Of course, you could send the appropriate CC messages in the correct order to make an NRPN message if you really needed to.
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Thanks. How do i send series of CC from Octatrack to make message a NRPN?
You may be aware that an NRPN message is made up of a series of 3 or 4 Control Change messages.
The official MIDI specification is here: https://www.midi.org/specifications
Here is an unofficial tutorial: MIDI NRPN and RPN by Phil Rees
So an NRPN message is made of two initial CC messages (99 and 98) to say which parameter is to be adjusted, and then one or two CC messages (6 and maybe also 38) to give the value of the parameter.
You need to look at the manual for the DSI synth to determine which values of these messages need to be sent.
You didn’t specify which synth, so here is an example for the Prophet '08:
Layer B LFO speed is NRPN number 237; the value of this NRPN to get “sequence speed divided by 1.5” is 158.
Therefore the four CC messages and values to send are:
CC 99 (value 1)
CC 98 (value 109) [because 1 x 128 + 109 =237]
CC 6 (value 1)
CC 38 (value 30) [because 1 x 128 + 30 = 158]
So you would need to send these four CC messages with these values in close succession from the OT.
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Excellent, thanks. The synth is DSI mopho. As per sending CC - do I lay down 4 trigless trigs on MIDI sequencer?
One trig is enough, trigless or not. CC order can matter.
NRPN worked for me with Micromonsta.
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Thank you very much. Manual for mt Mopho says that i can control lfo via nrpn #37. How would i program that?
Is it like that:
Cc99 - value 1
Cc98 - value 37 -> nrpn for LFO
Cc6 - value 1
Cc38 - value 30 -> that is 128+30=158
Almost! It should be:
CC 99 - value 0
CC 98 - value 37 [because 0 x 128 + 37 = 37]
CC 6 - value 1
CC 38 - value 30
Hope this works for you!
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Excellent! Many thanks
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Nrpn and sysex both confuse me , thanks for the explanation .
I tended to avoid them and do something else.
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Update: yes, it did work. Absolute happiness!!
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