Expander 1220
The 1220 vocoder expander unit pictured above this 221 is a one-off piece Synton built for Dutch broadcasting company NOS. It houses a pitch to voltage converter, CV freeze function and a ‘presto-patch’ edge connector for making analyzer-synthesizer patches
A spectrogram of the 20 filters, spaced in minor thirds.The four bands per octave create a diminished chord.
The sample below is a polysynth chord on carrier, a S&H sine on the speech input.
One channel is without voiced/unvoiced detection, the other switches to internal noise on unvoiced sounds.
The left and right sounds are recorded in different passes.
Used parts
CA3080
LM324
HA4741
LM301
XR4195
XR2207
TDA 1034/NE5534
Syntovox 221 Manual,
Review 221 sono france
VCO 221 schematics, 221 PSU schematics 221,_input schematics 221, Vocoder output mixer,
Only a small amount of these were made. Users include Wendy Carlos (who owns a 221 & SPX 216),
Bruno Spoerri, various electronic studio’s in Europe. Best suited for studio use due to complex control.
The 221 has a 50-pin connector on the back which provides CV in and out for each channel,
and other functions.
Block Diagram