Channels

FreePiano have 16 input channels, and 16 output channels.

What’s the difference between input and output channels?

A input channel is what you send signal to, and then freepiano translated the signal to a MIDI message to a MIDI channel, that MIDI channel is called output channel in FreePiano.

Multiply input channels can have signals outputed to a same output channel, parameters of input channel (most are note transpose) is calculated on a note before sending to output. MIDI channel have no such thing like ‘Transpose’.

Let’s take a look at the channel options in FreePiano:

Parameters of Input channel

Most parameters of input channel is used to transpose notes:

Parameter	Description
Velocity	Velocity when a note is pressed.
Transpose	Different to key signature, Transpose only affact a input channel.
Follow key	When checked, all notes is transposed to current key signature.
Octave	Transpose by octaves(12 seminotes)
Channel	Which channel the final MIDI message will send to.

Parameters of output channel

Output channel is MIDI channel, parameters translated into MIDI messages.

Parameter	Description
Bank	Controller 0 in MIDI, for controlling bank.
Program	Program Change in MIDI, for select voice on a channel.
Volume	Controller 7 in MIDI, for chagne volume on a channel.
Pan	Controller 10 in MIDI, for change pan on a channel.
Sustain	Controller 64 in MIDI, as sustain pedal.