The EXB-FW from Korg is a FireWire expansion board option for the M3 Music Workstation keyboard. It features two FireWire 400 ports, one to connect to a Mac or Windows computer, and the other to daisy chain an external drive to the host computer. The EXB-FW provides 2 channels of digital audio inputs and 6 channels of digital audio outputs through its FireWire 400 port. A MIDI input and output are also provided through the FireWire connection.
Having the EXB-FW installed enables you to utilize the Virtualized Hardware functionality of the M3. Virtualized Hardware allows you use your M3 as though it were a plug-in software instrument in the host DAW application of your choice. You can also sample sounds into the M3 from your computer, process audio from your DAW through the M3's effects, and control your other plug-in instruments with the M3's many hardware controls.