Apple Logic Pro 9 - Manual (Page 1133)

Channel Splitter Objects
A channel splitter routes MIDI events by channel. Every MIDI event received at the channel
splitter input is automatically routed to the output that corresponds to its MIDI channel.
If no cable is connected to the corresponding output channel, the event is rerouted to
the SUM output (at the top).
To create a new channel splitter object
µ
Choose New > Channel Splitter (or use the New Channel Splitter key command).
Chord Memorizer Objects
A chord memorizer maps individual notes to chords. You can assign one chord to each
pitch class (to C, C#, D, and so on).
The octave of the incoming note determines the octave of the resulting chord. A chord
can have 0–12 notes in it. (Zero and one-note chords can be useful for creating scale-filters
and scale-correctors).
The easiest way to use a chord memorizer is to connect its output to the instrument that
you want to play the chords through, and assign it to an arrange track. You can, of course,
place it anywhere else in the MIDI signal path.
1133 Chapter 37 Environment Objects Reference