Electrical audio signal processing systems and devices – Acoustical noise or sound cancellation – Adjacent ear
Patent
1991-08-26
1994-02-01
Peng, John K.
Electrical audio signal processing systems and devices
Acoustical noise or sound cancellation
Adjacent ear
381 72, 381 94, H03B 2900
Patent
active
052838340
ABSTRACT:
Detection of higher order mode transverse modal energy is suppressed for an acoustic wave propagating longitudinally through a duct. First and second microphones are placed in respective first and second nodal planes of the second higher order mode, and the outputs of the microphones are summed. For the first higher order mode, the output of the first microphone is equal in amplitude and opposite in phase to the output of the second microphone, and the resultant sum is zero. For the second higher order mode, the output of each of the first and second microphones is zero, and the resultant sum is zero.
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Burlage Kirk G.
Goodman Seth D.
Lefkowitz Edward
Nelson Industries Inc.
Peng John K.
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