On the measurement of electro acoustic enhanced sound fields

The installation and optimization of acoustic enhancement systems requires a large amount of experience. The verification in terms of measurement is most of the time done using conventional reverberation and acoustic parameter measurements according to ISO 3382. This is a good solution for diffuse sound analysis and general examination of early reflections, but in terms of direction dependent analysis the results are not satisfying. A room equipped with an acoustic enhancement system was measured using a circular array. The effects of adding specific early reflections and direction dependent diffuse energy generated by the acoustic enhancement system are investigated. The results are compared to standard measurements according to ISO 3382. For a future measurement system a psychoacoustic post-processing engine would be desirable to get information about the psychoacoustic impact of particular reflections. Based on such post-processing the semi-automatic calibration of an acoustic enhancement system will be conceivable one day. Circular array measurements and volume data representation are an useful tool for the installation and optimization of acoustic enhancement systems. Furthermore the execution of these investigations showed impressively that the human sense of hearing is a very powerful instrument for the evaluation of room acoustic properties.