MPE Modifier is a free MaxForLive device that does two simple tasks. It changes the incoming Slide and Pressure MPE messages into Control Change messages per voice, and also replicates global messages like ModWheel, Pitch Bend, and Aftertouch to all MIDI channels.
I designed this device to be used with the MPE Trackpad option in AudioSwift, but it should work with any MPE controller like Ableton Push 3. I also did it with U-he synths in mind, but feel free to use it with other virtual instrument plugins that don’t have full MPE support and work with multichannel MIDI, like Native Instruments Kontakt or Spectrasonics Omnisphere.
The main idea of MPE Modifier is to change the default MPE messages to other CC numbers the virtual instrument usually works with. Also, any other MPE MaxForLive device before the instrument will keep responding to the default Slide CC74 and Pressure messages.
Before designing MPE Modifier…
U-he synths like Hive and Diva are multichannel but don’t have full MPE support. They don’t usually work with the MPE standard Slide CC74. All of their patches have parameters mapped by default to CC1 (ModWheel), CC2 (Ctrl A) or CC11 (Ctrl B). We would need to manually map those parameters to CC74 inside the plugin or change the CC number sent in the MPE controller. Both workarounds come with limitations, specially changing the CC inside the controller, since we can’t later edit the MIDI clip envelopes per voice if the CC number recorded is not the default Slide CC74.
The other problem is with global messages that apply to all notes or voices. The MPE standard uses a Manager Channel (MIDI channel 1), to send the global ModWheel, Pitch Bend, and Aftertouch messages. U-he synths don’t use this Manager Channel and don’t apply the messages to the notes played in the Member Channels (MIDI Channels 2 to 16). Instead, the synths only apply these types of messages if they come in the same Member Channel as the Notes On/Off.
Welcome MPE Modifier!
Here is a video using the MPE Modifier with Diva and Arpex, an expressive MPE arpeggiator device designed by Mark Towers and sold on IsotonikStudios.
AudioSwift is sending the standard Slide CC74 and Pressure messages via X and Y axes on the trackpad. Arpex is only reading Slide CC74 to add octaves notes to the pattern. Pressure is passed thru to the MPE Modifier, which changes the messages to CC1 or ModWheel. Diva then uses CC1 to modulate the filter cutoff frequency.
If you want to try MPE Modifier, AudioSwift for macOS or get Arpex, please click the links below (Arpex is an affiliate link). And when you try AudioSwift, make sure to download our latest beta version, which includes a special Ableton Live Control Script for macros using your trackpad.
SPECIAL NOTE: Sustain is another global message sent through the Manager Channel. However, depending on your current Ableton Live version, sending Sustain to all Member Channels could not work and could cause the notes to hang on. If this happens, disable the virtual instrument or press the stop button several times. This is not a bug of MPE Modifier. As of this writing, MPE Modifier was tested with Ableton Live 11.3.12 and sending sustain to all channels doesn’t work.
