The SW984 Four Channel Matrix Mixer is an AC coupled 4-input, 4-output matrix with bass and treble tone controls for each output channel. Each input has a separate attenuator for each of the four output channels. Thus, a matrix of 16 input attenuators provides maximum channel separation, or variable combinations of volume balance. Tone controls for each of the output channels can attenuate or emphasize bass or treble signals. Flat signal response is achieved with the control settings kept at “5” on the potentiometers. These are 2-pole active tone controls.