Roland CM series
The Roland CM series is a line of sound modules intended to be used with computers. Each modules in the series is essentially a variant of one or two other modules from a different Roland series, but in a uniform plain box design with no panel controls or display.
Roland CM-32L
The Roland CM-32L is a variant of the Roland MT-32 LA synthesis multitimbral sound module, adding sound effects (presumably for use in games).
Roland CM-32P
The Roland CM-32P is a variant of the Roland U-110 PCM synthesis sound module. Like the U-110, it is expandable with a PCM card slot.
Roland CM-64
The Roland CM-64 combines a CM-32L and CM-32P into one box, on separate boards. The two synths are active simultaneously, listening on different MIDI channels.
Roland CM-300
The Roland CM-300 is a variant of the original Roland SC-55 GS sound module.
Roland CM-500
The Roland CM-500 combines a GS sound source (presumably similar to the CM-300) and CM-32L into one box. It has a switch that allows switching between several modes, among others a GS-only mode and a CM-64 emulation mode (the GS sound source emulates the CM-32P).[1] It does not have a PCM card slot. The GS sound source includes the CM-64 bank,[2] like the SC-55, even though the CM-500 also has a real LA sound source in it.