A new technique to measure electroacoustic transducer directivity indices in reverberant fields

The paper presents a new method for measuring the directivity index of an electroacoustic transducer in a diffuse reverberant environment. The method that is proposed relies on the measurement of the spectral density variance of the transfer function between source and receiver. The method requires a measurement of the source/receiver transfer function, the distance between source and receiver, the directivity of either of the transducers, and an estimate of the room constant. A variant of the method eliminates the room constant variable. The modified method is a comparison technique that requires a known source and receiver directivity and the distance between source and receiver. The methods and their limitations are discussed for computer simulated rooms and actual measurements made in a reverberant room