The Univox (1940)

Developed by the British 'Univox Company' the Univox was an instrument using a vacuum-tube sawtooth generator modulated by a diode waveform shaper circuit. The pitch range was extended to five octaves using a frequency division technique which also allowed the playing of multiple octaves of the same note from one key. The Univox keyboard had a unique a double contact system under the key allowed basic control over the note shape - striking the key harder caused a thyratron impulse generator make a shorter decay, creating a staccato effect, striking the key softly gave a long decay of up to two seconds. A vibrato oscillator was also provided to modulate the output and also to retrigger the thyratron tube to create 'mandolin' type repeated notes. 
The Univox had a front panel of fifteen switches to further control the timbre of the instrument, three vibrato controls, a thryratron modulation control and an overall knee operated volume control. The Univox had a an external amplifier and ten inch speaker unit. 

The Univox was noted for the realism in producing string and reed tones such as clarinet and saxaphone. 

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