A waveform data processing apparatus has a bus that transfers data signals representative of waveform data . A plurality of transmitting nodes transmit the data signals to the bus. A plurality of receiving nodes receive the data signals from the bus. A clock generator generates a word clock signal at each sampling period. A controller is responsive to the word clock signal for conducting a session of transferring the data signals within a sampling period, such that the transmitting nodes sequentially transmit the data signals in an order predetermined by the controller so as to avoid collision of the data signals within the sampling period, and each of the receiving nodes selectively admits a necessary one of the data signals outputted from the transmitting nodes and processes the admitted data signal within the sampling period.