A "
general purpose signal processing device for
audio tone
sources" from
Curtis ElectroMusic. Used as the
VCF and
VCA in many popular
analog synthesizers.
Features:
(from the original data sheet)
several components on one chip:
low external parts count
0 to +5V, high Z control inputs for direct interface to system DAC from CMOS multiplexer
VCF using open loop design for enhanced sound richness
VCF has constant loudness as resonance changes
TC compensated VCF
low level, non-inverting VCF frequency control input for easy mixing of control sources
Final VCA has low feedthrough without trimming
Synthesizers using the chip:
with the amount used
Akai AX80 8
Akai VX600 6
Sequential Circuits Prophet-600 6
Sequential Circuits Prophet-T8 8