The ASP231 from Audient is a dual channel, 31-band graphic equalizer with individual multiple feedback constant Q filters at ISO-standard third-octave frequencies. The output stage can drive very large amounts of current into the difficult loads often presented by long cable runs and paralleled loads, while the optimized balanced input stage provides superb rejection of unwanted signals in real world conditions.
The unit can operate in two modes. "Normal" mode, best suited for general EQ treatment and system correction provides reciprocal constant Q responses with smooth combining characteristics at all gain settings. "Narrow" mode provides a much sharper cut response, which allows removal of feedback with minimal loss of program material. Since overall system treatment may still be required in "Narrow" mode, the boost controls still operate with normal bandwidth.
To make compensation for audience absorption and humidity changes, the ASP231 feature a "Tilt" control that tilts the overall system response gently around the 1kHz mark, either boosting high-frequency and cutting low frequency, or vice versa. Center frequencies and operational controls are back-lit to enhance functionality in darker environments and long throw fluid damped 45mm centre detented precision faders provide a smooth response when operated.