MIDI source

The MIDI source is a powerful modulation source if you want more control over Volcano 2 using a MIDI keyboard or MIDI control knobs. Note that you first need to route data from a MIDI track to Volcano in your host.

To add a MIDI source as a modulation source, click the + button in the source selection bar and click New MIDI Source.

MIDI Input
Normally the MIDI source lets you use MIDI input such as velocity, pitch bend and modulation wheel to influence any parameter that can be modulated.
Controller number
... but when you set the input selection to Controller, it lets you use any MIDI controller as a modulation source.
Response curve
The response curve can be adjusted to get the desired control over the MIDI source output. For example, when used with velocity as MIDI source the linear, exponential, logarithmic, square, square root or sine curves make great dynamic differences.

Using a MIDI source is different from MIDI Learn because there is no direct control of a knob via MIDI but it uses a modulation slot instead. This way you can add modulation to an already modulated destination. Or you can use the full rotation of a knob while actually modulating a smaller range. This can be a good way to control say, the filter cut-off frequency or EG attack for which you sometimes want to make small changes with great precision.

At the top right of the source interface, the Presets button provides access to the MIDI source section presets. The Remove button deletes the MIDI source. You can customize the default MIDI source settings (used when creating a new MIDI source) by overwriting the predefined Default section preset.

Tips

When modulating filter frequency with pitch bend, the default slot level value corresponds to +/- one note of modulation (you can reset to the default value by Ctrl/Command-clicking the slot level). The maximum slot level corresponds to +/- one octave.
To let a sustain pedal control an envelope generator, use a MIDI source. Set the input to Controller, and the controller number to 64. Now, drag the source drag button for the MIDI source to the hold control point of the envelope generator, and set the slot level to maximum. Of course, you can also set up more sophisticated behavior of the sustain pedal, for example by modulation the release setting instead of hold: the possibilities are endless.
The VST 3 version of FabFilter Volcano 2 doesn't support per-note aftertouch modulation.

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