The disk drive used [Group Code Recording]? and contained a [6502 processor]? as a [disk controller]?. Some people wrote code for it to vibrate the head at different frequencies to play tunes.
The transfer rate was about 300 bytes per second. The 1541 used a bit-serial version of the [IEEE 488]? parallel protocol. Some third-party speed-ups could transfer about 4 kilobytes per second over the interface, and some "fast loaders" managed up to 10 kbps.
The [Commodore 1570]? was an upgraded 1541 for use with the [Commodore 128]?.
See also: Commodore 64, [Commodore 128]?, [Commodore 1570]?