This low-cost microphone mounts on a standard wall plate. The PZM-11 resembles a light switch rather than a microphone. Intelligibility is excellent, with low frequencies below the voice range rolled off to reduce the pickup of HVAC rumble. Electronics on the rear of the plate offer screw terminals, eliminating the need for connectors. Powering is via 24Vac, 12-24Vdc or 12-48 volts phantom power.