Roland SC-55

The Roland SC-55 (Sound Canvas) is a GS MIDI sound module released in 1991 by Roland. The SC-55 was the first sound module to incorporate the new General MIDI standard.

The SC-55 used both PCM and a cut-down version of the LA synthesis engine, to support 24-voice polyphony with 16-part multitimbrality. It came preloaded with the Roland MT-32's variation bank, but lacked the MT-32's re-programmability. Aimed at PC music enthusiasts, the SC-55 featured 317 instrument patches, including the GS drum kits and additional controllers. The selection of effects includes reverb and chorus.

Alongside the SC-55, Roland released the SB-55 (Sound Brush), an inexpensive MIDI sequencer module the same size as the Sound Canvas. Both the Sound Canvas and Sound Brush could be rackmounted alongside each other.

Other models with comparable tone generators include Roland CM-300, Roland CM-500 and Roland SC-155 sound modules. CM-300 and CM-500 models lack the LCD screen and extended controls of SC-55. Both models have external appearance nearly identical to Roland's earlier CM-32/64-series modules. SC-155 adds additional slider controls for master and channel level and panning. Additionally, CM-500 includes fully SysEx compatible LA tone generator similar to CM-32L's.

A minor upgrade to the original SC-55, the Roland SC-55mkII has increased polyphony (28 voices), more patches, raising the total number to 354 instruments and extended, and improved audio-circuitry in the form of 18-bit audio (versus 16-bit in the original SC 55.)

The SC-55mkII added a serial port as an alternative interface to the MPU-401.

Roland also released the Roland SCC-1, an 8-bit ISA half-size card incarnation of the SC-55 sound module. The sound source is controlled by an on-board MIDI Processing Unit, a variant of the MPU-401 unit. An updated version featuring the SC-55mkII sound set was also released, known as SCC-1A. When bundled with the Band-in-a-Box and BalladeGS software, it's called SCC-1B.

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