Live Measurements of Subwoofers' Performance

摘要

Various software-based measurement systems can be used for live sound measurements with music or speech signals in occupied concert halls with sufficient accuracy. However, for some special applications as measuring the performance of a ground-stacked bass array component of a multiple component sound reinforcement system in an occupied hall, these systems can't be used directly, since it is not possible to run a bass array alone during a concert. Two simple methods to obtain the subwoofers' impulse response using program signal measurements of a full range sound reinforcement system are proposed. In the first case the desired impulse response results from subtraction of full system impulse responses with and without subwoofers running. In the second a small delay is added to the subwoofers' signal, their impulse response is then calculated from the difference between the response of the full system with and without the delay. The comparison of both methods' results with a reference sweep measurement is presented, limitations and accuracy are discussed.