Split and Merge convert polyphonic signals to multiple monophonic signals and vice-versa. Refer to the Polyphony entry of Rack’s manual to learn about polyphony in Rack.

Split expands a polyphonic signal patched into the POLY input to multiple monophonic outputs labeled 1-8 and 9-16. If the polyphonic input signal includes less than 16 channels, all unpatched channels are considered to be 0V.

Merge joins multiple monophonic channels into one polyphonic signal at the POLY output. By default, the number of polyphonic channels is the index of the highest patched monophonic input. For example, if you only patch a cable to input 4, the polyphonic output will have 4 channels. Unpatched inputs are considered to be 0V. You can explicitly specify the number of output channels by right-clicking on the panel and selecting the “Channels” menu.

It is possible to create zero-channel polyphonic signals with Merge. See Polyphony Technical Details for an explanation of zero-channel cables.

The CHAN lights on both Split and Merge modules indicate the number of channels currently being processed. It is not possible to “deactivate” channels lower than the maximum channel number. All channels from 1 to the maximum channel number are “active”, even if they are 0V.