Reply: Crown makes four models of wall-mounted microphones for home automation and voice recognition:

PZM-10: Mic on a 1.5 inch circular plate, XLR connector, phantom powered. Mic-level output.
PZM-10LLL: Same as PZM-10 but line-level output. Permanently attached cable. Works on 12 to 24V DC.
PZM-11: Looks like a light switch. Screw terminal output. Works on phantom power or 12 to 48V DC. Mic-level output.
PZM-11LL: Same as PZM-11 but line-level output. Works on 24V AC, 12-14V DC, or phantom power as the PZM-11LLS2.

Mic-level output is about 1 millivolt, and line-level output is about 0.3 volt.

All the mics have a balanced, low impedance output so they can be used with very long microphone cables without hum pickup or high-frequency loss. Below is a link to the data sheets for those microphones. Datasheets are at the following website under the heading “PZMs for Security and Surveillance”.

PZM datasheets

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