ABSTRACT
In any event, both really reflection-decay time (RT) and cumulative energy measures are frequency dependent—confirmation that direct and steady-state sound fields have different spectra in most rooms. Much simpler sound fields work too, especially in multichannel sound reproduction where it is possible to deliver sounds to the ears that are perceived to have those qualities—with or without a reflective room. In sound reproduction, the essential hall reverberation is captured in the recording, so nothing additional is required. Sound reproduction spaces are much less reflective: the principal cues to space and envelopment are in the multichannel recordings, and volume control changes loudness at will. For sound reproduction, the process needs to be modified because the sound sources are the reproduction loudspeakers, and the venue reverberation is not expected to be a significant factor in the delivery of the program, whether it is music or movies. Loudspeakers have significant directivity, gradually increasing toward high frequencies.
