Casio VL-1

The VL-1 was the first instrument of Casio's VL-Tone product line, and is sometimes referred to as the VL-Tone. It combined a calculator, a monophonic synthesizer, and sequencer. Released in June 1979, it was the first commercial digital synthesizer, selling for $69.95.

It has 29 calculator-button keys (G to B), a three-position octave switch, one programmable and five preset sounds, ten built-in rhythm patterns, an eight-character LCD, 100-note sequencer, and multi-function calculator mode. The VL-1 is notable for its kitsch value among electronic musicians, due to its cheap construction and its unrealistic, uniquely low-fidelity sounds.

The VL-1 was followed by the VL-10, basically the same machine in a smaller unit, and the VL-5, a polyphonic version, capable of playing four notes simultaneously, but lacking the VL-1's synthesizer section due to the removal of the calculator mode.

Its sounds were mostly composed of filtered squarewaves with varied pulse-widths. Its piano, violin, flute and guitar timbres were nearly unrecognizable abstractions of real instruments. It also featured a "fantasy" voice, and a programmable synthesizer which provided for choice of both oscillator waveform and ADSR envelope. The synthesizer was programmed by entering a number into the calculator section's memory, then switching back to keyboard mode. It had a range of two and a half octaves.

The VL-1 featured a small LCD display capable of displaying 8 characters. This was primarily used for the calculator function, but also displayed notes played. As well as this, the VL-1 also had changeable tone and balance, basic tempo settings and a real-time monophonic music sequencer, which could play back up to 99 notes. There were also 10 pre-loaded rhythms which utilized just three basic drum sounds.

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