Analysing impulse response of enclosures with the aid of a charge transfer device

Abstract

In this paper the design of an electronic system for evaluating the hearing qualities of enclosures is introduced. The method makes use of the impulse response of the enclosure under test to evaluate the sound decay process according to the integrated impulse method. The time required for the sound to decay l0 dB below the steady state sound level is measured automatically out of this operation. The procedure is done by squaring and integrating the impulse response to obtain the process of sound build-up, a charge transfer device is used to store the successive values of the build-up process, these successive values are then used to obtain the decay process using a subtractor. The time required for the sound to decay 10 dB below the steady state sound level is evaluated using comparator, attenuator, and a digital counter.