A modular signal processor for digital filtering and dynamic range control of high quality audio signals

A high speed, low cost digital signal processor has been designed and built suitable for real-time operation on high quality audio signals. The machine is microprogrammed and so is potentially a hardware solution to many signal processing problems. The paper describes its application to audio equalisation and dynamic range control of a kind found in a range of broadcast and studio equipment. The reasons for the choice of filter structures and a method for dynamic range control are discussed with particular attention to the wordlengths required. The features of these structures are incorporated in a modular, hardware-efficient design which can be expanded to a large system under common control.