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

The PZM-10 is a small cylindrical model that works on phantom power.
The PZM-11 resembles a light switch wall plate, and works on phantom power.
The PZM-10LL is like the PZM-10 but provides a line-level output rather than mic level. It works on 12 to 24V DC.
The PZM-11LL is like the PZM-11 but provides a line-level output rather than mic level. It works on 24V AC or 12-24V DC.

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:

PZM datasheets

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