The SD4 can be used with a standard programmable MIDI footswitch.

You are responsible for reading and understanding the owner's manuals for both devices and programming the footswitch to suit the commands, such as Patch Changes. Not rocket science, and you can just set the footswitch up to send the standard GM MIDI changes alone and get quite a lot of sounds, or you can delve into programming the pedal to select sounds from the SD4's Upper Banks as well.

The same can be done with the little SD2 as well.

Here is a link to the Behringer corp. website description of their programmable MIDI Foot Controller, a good and affordable choice IMO:

http://www.behringer.com/EN/Products/FCB1010.aspx


--Mac