MIDI effect multi-channel ouput

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MisplacedDevelopment
Posts: 94
Joined: Sun Feb 28, 2021 9:40 am

MIDI effect multi-channel ouput

Post by MisplacedDevelopment »

DigiKeys lets you drive each of its 16 internal instruments by sending it MIDI on any of those 16 channels. I would like to drive DigiKeys in MTS using the piano roll but I cannot see a way of setting the channel on a per-note basis in the controller section. To try and work around this I added Atom 2 in the MIDI effect slot and added some notes to a few different channels in its piano roll. This same MIDI drives DigiKeys as expected in AUM/Cubasis but MTS seems to do some processing on the MIDI between the MIDI effect and the receiving plugin (possibly changing the channel of the notes to the track channel?). Would it be possible to remove any processing so that the raw MIDI is sent as-is between the effect and receiving plugin?

This is also an issue with multi-channel MPE. I recorded some MPE MIDI into Atom 2 routed to GeoShred Flute using Velocity Keyboard as the input with its “MPE Guitar” preset, which uses:

“ MPE-4: Legato support, limited to one note per string or keyboard. Multi-channel MIDI with one note per string or one note per keyboard. Use this if you need legato transitions between notes.”

This MIDI sounds correct when played back from Atom 2 in AUM and Cubasis but the same MIDI when loaded into Atom 2 as an MTS MIDI effect does not sound correct.
MisplacedDevelopment
Posts: 94
Joined: Sun Feb 28, 2021 9:40 am

Re: MIDI effect multi-channel ouput

Post by MisplacedDevelopment »

I added Drambo after Atom 2 in the chain as you can use that to view the incoming MIDI. Here is what I found when playing the following sequence from Atom 2:

C4 x 4 on channel 1
C4 x 4 on channel 2
C#4 x 4 on channel 3
C#4 x 4 on channel 4
D4 x 4 on channel 5
D#4 x 4 on channel 6

Drambo receives:
C4 x 4 on channel 1
C4 x 4 on channel 2
C#4 x 4 on channel 3
C#4 x 4 on channel 3 <- ?
D4 x 4 on channel 4 <- ?
D#4 x 4 on channel 5 <- ?

When Atom loops and starts playing the sequence again then the following plays:

C4 x 4 on channel 2
C4 x 4 on channel 2
C#4 x 4 on channel 3
C#4 x 4 on channel 3
D4 x 4 on channel 4
D#4 x 4 on channel 5

The above pattern is repeated on subsequent loops.

I see the same behaviour when Helium is used to output MIDI across multiple channels in place of Atom 2.

It seems that when the note changes then MTS assigns to it the next channel number in sequence rather than keeping the channel assigned to the note.

Edit: some reading suggests that this could be a round-robin method of ensuring each note is on its own channel for MPE purposes. If so then is there a way to disable this behaviour so that the channel information is used as-is?
Support
Posts: 1717
Joined: Fri Aug 27, 2004 2:17 pm

Re: MIDI effect multi-channel ouput

Post by Support »

MultitrackStudio MIDI tracks are single (MIDI) channel. This also applies to the MIDI effects: all output it creates will be on one channel.

MPE will be sent to AU instruments when per-note pitch bend or per-note brightness are sent to the plugin. You can avoid this by setting the per-note pitch bend range to zero. This setting is in the track's controller editor.


Giel Bremmers
MisplacedDevelopment
Posts: 94
Joined: Sun Feb 28, 2021 9:40 am

Re: MIDI effect multi-channel ouput

Post by MisplacedDevelopment »

Thanks for clarifying the behaviour, Giel. It is clear now that this particular workflow in not going to work inside MTS. The trick with setting the pitch bend to zero works as you described and may come in handy at some point in the future.
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