SI-24, Studio Package Pro, SPP: Do I need a MIDI interface?
The SI-24 Studio Interface has a MIDI interface built right into it. You can connect your MIDI keyboard controllers and sound modules right to the MIDI In and OUT ports on the back.
Please note: The SPP only functions as a 16 channel MIDI interface. If you need support for more MIDI channels, a multi-port MIDI interface is required.