Patent ID: 8467889

Claim:
An integrated circuit for mixing digital audio signals, the integrated circuit executing a predetermined number of steps of multiply-add processing on the audio signals every sampling period, the integrated circuit comprising: a signal inputting section that inputs a digital audio signal every step of the multiply-add processing; a level supplying section that supplies a level every step of the multiply-add processing; a level multiplying section that multiplies the inputted audio signal by the supplied level every step to control the volume of the audio signal; and an adding section that inputs and accumulates each level-controlled digital audio signal outputted by said level multiplying section, wherein the integrated circuit further comprises: a mode designation section that designates a mode defining a number J of channels and a number K of mixing buses, and wherein said adding section outputs a result of the accumulation as an output from a mixing bus and starts new accumulation for another bus every J steps in a sampling period, in accordance with the mode designated by said mode designation section, so as to realize an audio mixer having J input channels and K mixing buses.