Audio signal processing system

An audio signal processing system comprising:

• a transmission line that transmits a control signal and an audio signal;
• a plurality of signal processing units that are connected to the transmission line, each signal processing unit having a plurality of channels for applying a signal process to audio signals inputted thereto and outputting the audio signals to the transmission line after the signal process is applied;
• and
• a control unit that is connected to the transmission line for operating one or more channels belonging to one or more signal processing units by transmitting thereto control signals through the transmission line, the control unit having a display part and a plurality of color pallets which are different from each other and which are previously selected in correspondence to the plurality of the signal processing units for use with the display part, wherein when the control unit detects an instruction to display an operation screen on the display part for operating target channels belonging to different signal processing units, the control unit performs a process of rendering the target channels in the operation screen with using different color pallets corresponding to the different signal processing units to which the target channels belong, such that background colors of target channels belonging to different signal processing units are made different when all of the target channels are displayed on the display part of the control unit.