Hydrogen allows you to send both notes encountered during playback as NOTE_ON and NOTE_OFF messages and the current state of specific controls using MIDI Feedback as CC messages.
But first of all you have to set a MIDI Output device in the Preferences.
![[Note]](../img/admonitions/note.svg) | Note |
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The list of available MIDI output devices/ports is compiled for the current MIDI driver when opening the Preferences dialog. If you switch to another driver, be sure to click OK and reopen the Preferences dialog in order to have an updated list. |
Now every note encountered during playback will trigger a
MIDI note with the note's velocity and the channel and
pitch specified in the corresponding instrument. In
case the channel is set to off, no
MIDI message will be sent.
| Note |
|---|---|
To enable MIDI output, you have to
set both an output device in the
Preferences as well as all instrument
MIDI channels to a dedicated value, like |
You can also keep other MIDI-capable applications
posted about parameter changes in Hydrogen using
MIDI Feedback. If one or more CC events are mapped to a parameter supporting
feedback, all of its changes - also those triggered by incoming
MIDI messages - will cause Hydrogen to send a CC
message. This message will carry the same message parameters as the
one mapped to the particular parameter within Hydrogen and will
contain its value mapped to a range between 0 and
127.
Supported feedback parameters are
Volume faders, Pan rotaries as well as Mute and Solo buttons in the Instrument Channel Strips.
Volume fader and Mute button of the Master Fader Strip.
Metronome button.