AU keyboard sending on multiple channels

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

AU keyboard sending on multiple channels

Post by MisplacedDevelopment »

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

Re: AU keyboard sending on multiple channels

Post by MisplacedDevelopment »

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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Joined: Fri Aug 27, 2004 2:17 pm

Re: AU keyboard sending on multiple channels

Post by Support »

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

Re: AU keyboard sending on multiple channels

Post by MisplacedDevelopment »

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

Re: AU keyboard sending on multiple channels

Post by MisplacedDevelopment »

Some initial testing shows that the new Audio -> MIDI function seems to let you play multiple tracks of MIDI channels from a single plugin, which is what I was trying to do in the OP. I don’t know if this new feature enables this or it was there all along and I had missed it. For example, to use a MIDI clip launcher from within MTS:

1. Enable LK as an effect from the plugin editor and add it to an audio track
2. Create 2 tracks inside LK, one pointing at MIDI chl 1 and the other at chl 2
3. Create 2 MTS MIDI tracks, listening on chl 1 and 2 respectively.
4. Set all tracks to ‘P’ mode by double-clicking on their play buttons.
5. Set “Mon” soft monitoring on.
6. (Optional) I also set the audio input to AB to avoid feedback as I did not have an audio device attached.

Now, if you play clips in LK then the MIDI is directed to the tracks listening on the relevant ports. The transport does not need to be engaged for this but if you set the MIDI tracks to record mode then you can record the MIDI performance coming from LK.

Edit: there remains the small matter to solve of how you get MIDI into LK as it is hosted in an audio track :)
Support
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Re: AU keyboard sending on multiple channels

Post by Support »

Besides the audio-->MIDI thing there's something new in 4.3: The output of AU plugins used to be merged into a single MIDI channel. It no longer does that, so recording the output to multiple MIDI tracks like you suggest is now possible.

It didn't make it to the whatsnew list because I didn't know how to describe it. You've found it amazingly fast :-)

An AU MIDI effect in the MTS MIDI keyboard can now send to multiple channels, and you can record these channel to different tracks. I guess that should have been on the whatsnew list ;-)


There's something else that might be of interest to you: the per-note articulations combined with the 'Raw MIDI Channels' Articulation preset allow you to send notes to a specific MIDI channel. It's not something you're supposed to be doing in MTS, but if you really want to you can do that now.


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

Re: AU keyboard sending on multiple channels

Post by MisplacedDevelopment »

All very cool. I will need to set some time aside to see where these new abilities take me.
MisplacedDevelopment
Posts: 94
Joined: Sun Feb 28, 2021 9:40 am

Re: AU keyboard sending on multiple channels

Post by MisplacedDevelopment »

Hi Giel, I have tried using a multi-channel AU MIDI effect such as Atom 2 or LK as a keyboard but I see the same behaviour as before where all data is sent to either the active ‘P’ track or the first one if there are multiple selected. I tried with/without autodetect keyboard enabled. Is there something else that needs to be set up for this to work?

I also tried using the MIDI channel articulation. I set up an instrument using the RAW MIDI channel preset and edited some notes to be set to channel 2. At this point I’m not sure if the notes were meant to sound on the track(s) listening on channel 2 or whether it would send a MIDI note on channel 2 to the AU on the host track but neither seem to happen. I put a MIDI monitor on as a MIDI AU and saw the note appear with the channel set to the one for the track (3) but did not see any for channel 2. Might I need to turn off those controllers that were mentioned a while ago for controlling multi-timbral mode?

Thanks.
Support
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Joined: Fri Aug 27, 2004 2:17 pm

Re: AU keyboard sending on multiple channels

Post by Support »

MisplacedDevelopment wrote: Tue Oct 05, 2021 4:48 pm Hi Giel, I have tried using a multi-channel AU MIDI effect such as Atom 2 or LK as a keyboard but I see the same behaviour as before where all data is sent to either the active ‘P’ track or the first one if there are multiple selected. I tried with/without autodetect keyboard enabled. Is there something else that needs to be set up for this to work?
I can't get that to work either :shock:
Will look into that.
MisplacedDevelopment wrote: Tue Oct 05, 2021 4:48 pm Hi Giel, I have tried using a multi-channel AU MIDI effect such as Atom 2 or LK as a keyboard but I see the same behaviour as before where all data is sent to either the active ‘P’ track or the first one if there are multiple selected. I tried with/without autodetect keyboard enabled. Is there something else that needs to be set up for this to work?
1)
First, let's try something that will work:

- add a new MIDI track
- load the "MIDI Monitor" AU in the instrument slot
- load the "Raw MIDI Channels" articulation preset
- add some notes with per-note articulations
- play back the notes.

Now you should see the notes in MIDI Monitor, and they should have the channels you assigned to them.

2)
The per-note articulations don't work if you use an AU MIDI Effect in the track.
The MIDI 2.0 note-on attribute is used for the articulation setting in the Note Editor.
The MIDI effect needs to pass these values through. A MIDI 1.0 plugin can't do this, so the per-note articulation values will be lost if you use a MIDI effect AU in your track.

FTR: this is what the desktop manual says about articulations: https://www.multitrackstudio.com/midiin ... iculations


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

Re: AU keyboard sending on multiple channels

Post by MisplacedDevelopment »

I gave it a spin with DigiKeys as an instrument and does work as you suggest in (1) where each note is sent to a different DigiKeys instrument depending on the channel used for the note. As you say in (2), there is a different behaviour if a MIDI AU is used and that is by design. Thanks.
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