Field‐type acoustic wattmeter

TLDR: The field-type acoustic wattmeter as mentioned in this paper is a powerful tool for measuring the sound power output of speakers, the noise power of machines in place under operating conditions, the sound absorption of walls, ceilings, and floors, the performance of sound-reproducing systems in rooms, and the sound field in rooms.

Abstract: The field‐type acoustic wattmeter [Olson, U.S. Patent 1,892,644 (1932)] consists of a velocity microphone responding to the particle velocity in a sound wave, a pressure microphone responding to the sound pressure in a sound wave, and an electronic means for combining the outputs of the microphones so the ultimate output of the system indicates the acoustic energy flow in a sound field. The electronic system is all solid state. The field‐type acoustic wattmeter is a useful and powerful tool for measuring the sound power output of loudspeakers, the noise power output of machines in place under operating conditions, the sound absorption of walls, ceilings, and floors, the performance of sound‐reproducing systems in rooms, the sound field in rooms, etc.