The Solovox was designed by engineers Alan Young, John Hanert, Laurens Hammond (speaker cabinet) and George Stephens of the Hammond Organ Co and manufactured in the United States between 1940 and 1948. The Hammond Solovox was a monophonic ‘keyboard attachment’ instrument intended to accompany the piano with organ type lead voices – similar to the Clavioline and Tuttivox. The three octave short keyed keyboard was stored on a sliding mounting under the piano keyboard with a knee operated volume control. The instrument was connected to an electronic sound generation box, amplifier and speaker housing by three thick cables and derived it’s sound from a single LC oscillator with a one octave frequency range – the signal from which was then passed through a series of 5 frequency dividers to create a further two octaves.
The Solovox (J+K models) used two vibrating metal reeds modulate the oscillator frequency to create a vibrato effect, in later models this was replaced by a second oscillator acting as a vibrato oscillator.On the front of the instrument below the keyboard there were a series of large thumb operated buttons for oscillator range (switchable +/- 3 octaves: ‘soprano’, ‘contralto’,’tenor’ , ‘bass’), vibrato, attack time, ‘deep tone’, ‘full tone’, ‘1st voice’, 2nd voice’, ‘brilliant’ and a switch for selecting woodwind, string sound or mute. The Solovox was able to create a range of string, woodwind and organ type sounds and was widely used in light music of its time.