Correlation techniques in studio testing

Correlation techniques allow the separation of signals which have arrived by paths of different transit times or originated from different sources. This ability is of assistance in certain types of acoustic testing in studios or other enclosures. The construction of an analogue correlator to derive the correlation function between two signals is described. Its application both in laboratory and in field measurements has confirmed and supplemented results obtained by other techniques. Sound reduction measurements and the identification of flanking paths have proved to be the area in which the technique has the greatest value. Details of laboratory and field measurements are included in the paper