Anyone have any luck with NRPN?

Elektron Gear Octatrack
#21

I guess I thought that LSB commands were NRPN-exclusive, that is not the case?

#22

Indeed, that is not the case.

Most MIDI messages usually have one Status byte followed by one or two Data bytes. For some functions a single message is insufficient so two MIDI messages are used. In order to allow the possibility for more than 128 banks, the MIDI specification allows for the bank number to be split into two parts when required, which are labelled the Most Significant Byte (MSB) and Least Significant Byte (LSB).

You were probably thinking of the differences between MIDI Control Change and NRPN messages. CC messages have one Status byte and one Data byte, but CC messages can be paired (in fact, Bank Select messages can be thought of as a special example of this. Non-Registered Parameter Numbers (NRPN) are messages that have two bytes (MSB and LSB) for the parameter number and one or two bytes for the parameter value, so they allow a wider range of parameters to be controlled over a wider range of values than CC messages allow.

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#23

Thank you for the explanation! I suppose I’ll have to figure out another way of changing Arp to On, might have to gasp do it by hand.

Edit: I was able to get the same sound from the OT Arp that I wanted from my X4, so I just trig-locked the notes I wanted to have Arp on, crisis averted!

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#24

In many cases it’s not necessary to always send the full NRPN sequence. In the case of DSI synths I’ve experienced that the Tetra will accept that you initially send the CC99:X, CC98:Y sequence separately (where X, Y is rerpresenting the parameter you want to edit). Then you can send the CC6:A, CC38:B arbitrarily (A, B representing parameter values MSB, LSB). Often you can tweak the parameter using only CC38.
In the case of my Tetra this will work until I send a new CC99, CC98 sequence to ”open up” for a new parameter.
When done it’s advisable to send CC99:127, CC98:127 which will close the NRPN reception to avoid accidental changes from stray CC:s.
Some synths, like the Tetra, will also accept the increment/decrement messages; CC96, CC97 when NRPN is ”opened”.