The Particles effect module generates multiple short notes that are randomly distributed on all notes incoming on the notes-input port.

It uses the same particles engine used for visual particles generators: Depending on the emission rate, it will regularly play short notes. The emission rate defines how often a note will be generated, and the random emission rate defines how regular the emission will be (with a random emission rate = 0, it will act like a metronome).

So if you for example connect the MIDI out port of a keyboard with the notes input port of the particles module, and then play a chord on the keyboard, then the particles engine will randomly pick one of the notes of the chord and play a short note with the same note value.

In the settings, you can set all kinds of parameters, like the emission rate, random emission rate, duration and velocity, and the randomness of each of these.

And in combination with these settings, there are also input ports for any of these parameters. By connecting any green output port to these input ports, you can dynamically control these settings.

The connected ports will not override the values from the settings, but multiply them. So if you for example have an emission rate of 5.0 set in the settings, and have the hand tracking x-value connected to the emission rate input port, you will get an emission rate of 0 when your hand is on the left and an emission rate of 5.0 on the right.

By setting these values in the settings and changing the settings of the lines connecting the two green ports, you should be able to define all kinds of combinations this way.