PURPOSE: To simplify the programming processing a delay data in the case of generating a reflecting sound by providing an address control device setting the address space of an external delay RAM for storing the result of calculation independently of L and R channels.

CONSTITUTION: In an external delay RAM for storing the result of calculation, an L channel write address register 102 fixes '1' to the MSB to allocate a high-order address space of the RAM and an R channel write address register 109 fixes '0' to the LSB to allocate a low-order address space of the RAM. As for the control of each channel, the L and R channels are selected by a data multiplexer 105, an address is outputted from a data bus 107 and the transmission reception of the data is implemented by a data bus 115. Thus, the delay in the L and R channels is independently controlled.