DSP digital signal processor A special-purpose microprocessor designed to handle signal-processing applications very quickly. DSPs are used in several classes of computer hardware, including sound cards, modems, telephony boards that handle sound and modem functions and hardware that handles audio and video compression in real time. When peripheral makers tout their DSP-based hardware, they're usually referring to chips from Analog Devices or IBM/TI that can be reprogrammed with microcode. See also: codec