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.