The Sound Semiconductor SSI2164 provides four independent, high-performance VCA’s in a single package. A versatile Mode control allows selection of Class A, Class AB, or in-between using a single resistor to optimize noise versus distortion performance. Current input and output of audio signals provides design flexibility, with ground-referenced -33mV/dB control ports. Further flexibility is provided by the SSI2164’s four-fold increase of input current handling over the SSM/V2164 which allows reduction of RIN/ROUT values for lower noise at little to no cost in THD. The SSI2164 will operate on supplies as low as ±4V for battery-powered devices, or up to ±17V in systems where maximum headroom is desired. Distortion performance is improved across the board compared to the SSM2164/V2164. Depending on bias mode selection, extremely low noise (-96dBu typical, Class AB) or distortion (0.025%, Class A) can be achieved. The SSI2164 offers low control feedthrough, channel-to-channel gain matching better than 0.25dB, and a wide gain range of 120dB.