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A complete monolithic state variable filter is described which has been fabricated with bipolar technology. Two-quadrant multipliers are used in a novel fashion to achieve integration time constant large enough for audio purposes. Voltage control of frequency response from 20 Hz to above 20 kHz has been achieved without sacrifice of accuracy (notch depth >50 dB, low-pass and bandpass responses accurate to better than 0.1 dB), dynamic range (>90 dB), power supply rejection (PSRR>40 dB) or frequency drift (<200 ppm//spl deg/C). The design has been shown to be generally useful in the design of self-contained bipolar filters.