Objective Measures of Listener Envelopment in Multichannel Surround Systems

A common goal in multichannel musical recordings is to create a better approximation of the concert-hall experience than can be achieved with a traditional stereo reproduction system. Listener envelopment (LEV) is known to be an important part of good concert-hall acoustics and is therefore desirable in multichannel reproduction. In the present study a series of subjective tests were conducted to determine which acoustic parameters are important to the creation of LEV. It is shown that LEV can be controlled systematically in a home listening environment by varying the level and angular distribution of the late arriving sound. While the perceptual transition point between early and late energy has traditionally been set to 80 ms when predicting LEV, this matter has not been investigated rigorously. Subjective tests were conducted wherein the temporal and spatial distributions of the late energy were varied. A new frequency-dependent objective measure GS perc was derived, and it was shown to outperform other objective measures significantly.