The Audioaccess PX-603 Multiroom Expander adds areas of music to zones of the Audioaccess multiroom audio systems. The unit contains three stereo amplifiers in a single chassis. Each pair of channels has independent digitally controlled volume and selectable fixed equalization. Designed specifically for use with Audioaccess Multiroom Controllers, the PX-603 enables the system to add up to three areas of independent volume control to any existing zone, or zones, without the use of auto formers. The PX-603 is fed by fixed-level outputs and is controlled by the PX-700, or the PX-600 via the keypad bus. It is ideal for use in areas where background music is desired.