MIDI Connection
What do I need to connect a Roland RD-150 keyboard to run GarageBand?
MacBook, Mac OS X (10.4.11)
The Roland has standard MIDI in/out connectors (the round sockets with five smaller sockets in a half-circle inside them): you need a USB-MIDI interface such as this simple one from Edirol:
http://www.rolandus.com/products/productdetails.aspx?ObjectId=732&ParentId=114
Edirol do other interfaces:
http://www.rolandus.com/products/productlist.aspx?ParentId=114
(the latter page includes audio interfaces but what you need here is a MIDI interface).
As you are presumably aware, connecting it this way enables the Roland to run the software instruments within GarageBand, not allow GarageBand to record its own inbuilt sounds - for that you would need an audio interface (and of course the result would be an audio recording which you could not edit note-by-note).
http://www.rolandus.com/products/productdetails.aspx?ObjectId=732&ParentId=114
Edirol do other interfaces:
http://www.rolandus.com/products/productlist.aspx?ParentId=114
(the latter page includes audio interfaces but what you need here is a MIDI interface).
As you are presumably aware, connecting it this way enables the Roland to run the software instruments within GarageBand, not allow GarageBand to record its own inbuilt sounds - for that you would need an audio interface (and of course the result would be an audio recording which you could not edit note-by-note).