Best Ceiling Speakers for conference rooms

Almost every ceiling speaker in a commercial building runs on a 70V distributed line, not at 8 ohms, and the tap setting on the back of each one decides how much of the amplifier it takes. Order the wrong impedance and nothing works; set every tap to its maximum and one room eats the budget for the floor.

The other half of the job is above the tile. A back can is what stops the ceiling void turning into an unpredictable enclosure and what plenum-rated construction requires, and it is what an inspector asks about. Count the tiles, not the room: coverage is a spacing calculation from ceiling height, and guessing it is what produces a room that is loud under one speaker and dead between two.