AU keyboard sending on multiple channels

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

AU keyboard sending on multiple channels

Post by MisplacedDevelopment » Fri May 28, 2021 8:41 am

I’m trying to use a MIDI generator as the AU keyboard which outputs on multiple MIDI channels and record each of these channels to separate tracks. Examples of apps which output data such as this are Atom 2 or DigiKeys.

I am trying to understand the rules used to determine where MIDI is sent to from the keyboard instrument. In my test I have two tracks, listening on channel 1 and 2 and both are in practice mode to make them eligible for input.

* Options -> MIDI Channel lets an internal keyboard send to the channel indicated in the top right of the plugin on each track. That makes sense and works as expected, even allowing multiple Practice mode tracks to receive the same keyboard input if set to the same listening channel.

* I then load an AU keyboard, e.g. KB-1 and this has its own MIDI channel settings. Regardless of what these are set to, what the Options -> MIDI Channel is set to, and what the Autodetect Keyboard Channel option is set to, then the MIDI is sent to channel 1 and whatever track is listening on this channel.

* If I set only one track to Practice mode then this track then receives all of the MIDI but all channel information in the MIDI data is replaced by the receiving track channel number.

* With Autodetect Keyboard Channel unset then no MIDI is received by the track(s), even if there is only one track set to Practice mode and the plugin is sending MIDI on the channel that the track is set to listen to.

There are a combination of different variables at play:

* Options -> MIDI Channel
* Channel setting for each track
* Autodetect Keyboard Channel setting
* AU keyboard MIDI channel selection
* AU keyboard multiple simultaneous channel output, with the possibility of MPE output which complicates things further as there are situations where you *would* want to funnel this data rather than send each channel to different tracks.

I’m pretty sure I cannot currently do what I’m trying to do but are there any plans to add more options in this area? I’m thinking at least an option for multiple Practice tracks to receive only MIDI channel data corresponding to the track channel setting.

MisplacedDevelopment
Posts: 31
Joined: Sun Feb 28, 2021 9:40 am

Re: AU keyboard sending on multiple channels

Post by MisplacedDevelopment » Sat May 29, 2021 7:52 am

I have done a few more experiments and I think I understand the internal routing a bit better now:

* If only one track is in practice/armed mode then it receives MIDI regardless of the internal keyboard channel setting.
* If multiple tracks are in practice/armed mode *then* the keyboard channel setting is used. If none of the practice/armed mode tracks match the keyboard channel then none play.
* The above rules also apply to external MIDI being sent in.

I am still scratching my head over the rules for external AU keyboards so I’ll take a closer look there today.

One thing that caught me is that AUs can independently receive MIDI from the input source. I could not work out why the track which hosted Kaspar AU was playing even though it was on a different channel and then realised it had its own MIDI input preferences which were picking up the MIDI coming in via the AB3 virtual MIDI port. Once I turned off the MIDI receive settings from inside Kaspar then all was well.

Support
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Re: AU keyboard sending on multiple channels

Post by Support » Sat May 29, 2021 12:09 pm

MisplacedDevelopment wrote:
Sat May 29, 2021 7:52 am
I am still scratching my head over the rules for external AU keyboards so I’ll take a closer look there today.
The onscreen MIDI keyboard sends its output to single MIDI channel. This also applies to an AU plugin that's embedded there. Perhaps this is something that needs to be reconsidered.
MisplacedDevelopment wrote:
Sat May 29, 2021 7:52 am
One thing that caught me is that AUs can independently receive MIDI from the input source.
An AU shouldn't do that IMO.


Giel Bremmers

MisplacedDevelopment
Posts: 31
Joined: Sun Feb 28, 2021 9:40 am

Re: AU keyboard sending on multiple channels

Post by MisplacedDevelopment » Sun May 30, 2021 4:31 pm

Thanks, it would be very useful if there was an option to split out the output of the AU keyboard MIDI to the respective active MTS track channels. This would assist with the currently popular clip orchestrator workflow as you could host Atom 2 or LK as the AU keyboard and then use them to trigger, for example, Atom 2 patterns hosted in the MIDI effect slot. If the AU keyboard could (optionally) continue to receive timeline updates when it was closed, so that events would continue to be sent, then this would be even better.

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