It also includes a rudimentary sequence recorder, preset rhythms and chord accompaniment.
The SK-1 was thus an unusually full-featured synth in the sub-US$100 (equivalent to $280 today) home keyboard market of the time.
The SK-1 includes one pre-arranged piece of music, the Toy Symphony, which is played when the "Demo" button is pressed.
[3] The Radio Shack version of the Casio SK-1 is called the Realistic Concertmate 500.
It became very popular in the late 1990s among the circuit bending crowd after the first guide to bending it was published by Reed Ghazala in Experimental Musical Instruments magazine, though the SK-1 was being modified as early as 1987 when Keyboard Magazine published an article on adding MIDI support.