Delivering a stand-out bass response, the NV-SUBAMP500-xx subwoofer amplifier offers maximum performance with a convenient front-mounted screen and menu system with a rack-mount design. The amplifier and optional NV-SUBIWDUAL8 passive in-wall subwoofer are designed to integrate with almost any audio system. The variable crossover and phase controls selectable from the on-screen menus allow you to match the Subwoofer output with the main speakers for premium performance and sound. 12VDC Input and output triggers allow external devices to control the amplifier or for it to control external items. Three EQ menu settings allow the amplifier output to be tailored to any Nuvo in-ceiling or in-wall passive subwoofers. One or two NV-SUBIWDUAL8 subwoofers may be used with one NV-SUBAMP500-xx.