How to implement after touch in a Kyma sound.

Question

I have been trying to get a Kyma sound to interpret after touch (or MIDI key pressure messages after the note attack for a held note).

I can see the after touch MIDI events are being received as I see "press" messages in the MIDI Event Log, these are different message to key down/velocity messages.

I have read the manuals and they mention that the MDI channel pressure is mapped to !ChannelPressure (aka after touch).

!ChannelPressure is also listed in the reserved words list: https://kyma.symbolicsound.com/qa/2130/where-can-i-find-list-of-reserved-words-for-parameter-fields?show=2130#q2130.

However, when I use the variable as a parameter in a sound (for example in the "Frequency" box of a sample), the reserved word is not recognised and it appears as a literal variable on the VCS tableau when the sound is run - it then acts like a normal ad hoc variable.

I have seen a mention that !KeyVelocity is dynamic and runs for the life of a key press (https://kyma.symbolicsound.com/qa/2528/mpe-channelpressure-polyphony?show=2528#q2528) however, I do not see this behaviour - modulating key pressure on a sustained note does not affect !KeyVelocity. !KeyVelocity works well for the initial attack of a note, but the sustain of the not seems unaffected by it.

I have tried to find an example of the use of !ChannelPressure in the Kyma examples but could not find one.

Have I missed something?

Any suggestions would be helpful. Thanks

Answer 1

Hello Alex,

If this is a standard MIDI keyboard (not MPE), then polyphonic aftertouch appears as !KeyTimbre in Kyma. If it's an MPE keyboard, then other MIDI messages are used to update velocity and timbre.

Comments

Thanks for the information.
It seems the MPE keyboard creates Mono Key Pressure messages. Another keyboard creates Poly Key Pressure messages which get mapped to !KeyTimbre - which works. I see both types go through the MIDI monitor in Kyma.
Is there a manual page showing how I can pick up the MPE messages and use them?
Thanks Alex