Robin Gareus http://gareus.org/
6 Pedalboards using it

MIDI Chord

Plugin screenshot

Harmonizer - make chords from single (fundamental) note in a given musical scale. The scale as well as intervals can be automated freely (currently held chords will change). Note-ons are latched, for multiple/combined chords only single note-on/off will be triggered for the duration of the combined chords. If a off-scale note is given, it will be passed through - no chord is allocated. Note: Combine this effect with the 'MIDI Enforce Scale' filter to weed them out.

Control Default Min Max
Filter Channel 0 0 16
Scale 0 0 11
prime 1 0 1
3rd 1 0 1
5th 1 0 1
6th 0 0 1
7th 0 0 1
octave 1 0 1
9th 0 0 1
11th 0 0 1
13th 0 0 1
bass 0 0 1
latency 0 0 192000
http://gareus.org/oss/lv2/midifilter#midichord v.1:1033.31-10