The SPCV341.000 Audio Expander extends the acre Intrusion system via X-BUS with an audio verification zone, 4 wired zones and 1 line output to drive an external audio pre-amplifier. The built in microphone and speaker allow pre- / post-event audio recording and live audio (listen / talk) between ARC/CMS and the acre Intrusion system. Up to 3 audio satellites (SPCV310/410) can be connected to the expander.