JPS5479081A - Reverberation time measuring apparatus - Google Patents

Abstract

PURPOSE: To obtain a measuring apparatus capable of performing rapid and accurate measurement by calculating reverberation time by specific formulas through the application of an impulse integration method.

CONSTITUTION: A signal generating part which generates band pulse waves for measuring reverberation time with the band pass filter 4 of a gate circuit 11a by dividing down the internal clock signal of an ROM 1 for control and calculation with a frequency divider 2, an RAM 1 (8) which receives the microphone output which have received said pulse waves at the sound receiving point after passing the same through a gate circuit 11c and radiating to a sound field, as an input signal, and passing said input signal through a band pass filter 4, Schmitt trigger circuit 6 and A/D converter after the (t) second from the inputting of said input signal and stores the same for the T second and an RAM 2 (9) which stores the output of the A/D converter after the τ second from the finishing of the storage into the RAM 1 are provided and the reverberation time is calculated from the storage signals of the RAM 1 and RAM 2 by the formulas 4, 5. Thereby, the rapid and accurate measurement may be performed.

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