The PM-804A is an audio matrix mixer with 8 inputs and 4 outputs. Four of the inputs are mic / line selectable sensitivity and three-band EQ, and the other four are line. All eight are dynamically assignable to any output from the front panel, with individual volume and tone adjustment. In addition, the mixer can be controlled remotely from a four-zone microphone desk for sending live messages (PM-4Z), from wall controls that accept a microphone or line audio input (WP-1), or from managers of pre-recorded messages with zone selection and time control type SMM-8SA.