Noise suppression in an acoustic cavity.

The purpose of this project was to design and build an acoustic cavity having one boundary be an actively controlled flexible aluminum plate and to test the effectiveness of active sound pressure reduction. By controlling the plate vibrations, the sound pressure level in the cavity may be significantly reduced. The aluminum plate was equipped with piezoceramic patches affixed at different locations as sensors and actuators. By using active noise cancellation when the cavity was excited by an offending noise in the frequency band of 50Hz to 350Hz, the best sound level reduction cancellation of 11dB occurred at 230Hz, thereby validating the hypothesis