The AK7712A is a DSP(Digital Signal Processor) with built-in high performance 20bit 2ch ADC and 4ch DAC, on purposeto control the sound field. It is possible to calculate 383 steps on 44.1kHz and 48kHz sampling respectively. In case of 32kHz sampling, it can caluculate up to 511 steps. With a combination of this LSI and external memory for delay data,it can berealized easily to control the sound field such as Echo, Surround Presence Controller, and Key-control which are needed forsomething like Karaoke. Parametric Equalizing can be done without external memory.