An audio signal data processing system comprises input device for sequentially supplying an audio signal data, data memory control device for writing the audio signal data into a data memory and reading-out the data from the data memory, delay memory control device for sequentially reading-out the audio signal data from the data memory and storing the data into a location of a delay memory indicated by a writing address and for reading-out the audio signal data from a location of the delay memory indicated by a reading address and writing the data into the data memory, address designating devices for designating the writing and reading addresses, arithmetic device for multiplying a predetermined coefficient data to the audio signal data having been read-out by the delay memory control device and written into the data memory, and output device for providing the audio signal data in accordance with a result of operation by the arithmetic device. The data memory control device and the delay memory control device write and read the audio signal data into and from the data memory through data buses independent from each other.