Things have changed a bit with the CMK3 keyboards because they have built-in USB interfaces.
If you plan to use an external USB interface, you can still hook the CMK3 keyboards the same way as the CMK2. See our video tutorial.
However, if you want to use the CMK3 built-in USB interface, there are two ways you can hook them up.
1) You can daisy chain them (assume the top keyboard in the picture is the top keyboard in your stack)
How to configure the keyboards for configuration with CMK Config ONLY.
AFTER configuring with CMK Config, change the configuration to the configuration below. Move the USB from the top keyboard to the bottom keyboard. Remove the loop cable. Note: you may wish to plug your pedalboard output into the input of the TOP keyboard at this point.
2) Alternately, you can hook go USB from each keyboard directly into the computer. However, you MUST set each keyboard on a different channel.