Impulse Response Measurements Using All-Pass Deconvolution

Introduction It is often desirable to measure the impulse response of a particular system. In many cases the best way to do this is to apply a signal to the system which is close to a delta function - a click - and to measure the resulting output. In room acoustics this is traditionally done by using a blank pistol as the sound source, and recording the impulse response on a tape recorder. In seismology an explosive charge is often used for the same result. A problem with explosives is that they are not very repeatable, and the spectrum of the impulse that they produce is frequently complicated. In addition the high peak power they produce can present problems for the system under test, creating nonlinearities which can change the result of the test. For example, in a hall with an electronic reverberation system the high peak pressure of the pistol will probably overload the electronics, and the response of the electronics will be much lower than if music were used as an excitation. I