Specifications

5.1-Channel Production Guidelines Production Techniques
5-4
Signals might interact with each other causing the phantom image to conflict with the
true center image. In systems using dissimilar speakers, or in cases where the listeners
are seated off the central axis, the sound arrivals from all three speakers may not
blend well. Differences in arrival time can cause a comb-filtering effect, shifts in
tonal color, or a smearing of the image. Consider all of these effects when placing the
exact same signal in all three front channels. To counteract these effects, process the
additional signals first to change their spatial character, timbre, or prominence
relative to the main center signal.
5.3.2 Surround Channels
Whereas center-image signals were always part of mixing for stereo, surround
channels offer a completely new sonic dimension to consider. Using stereo surrounds
is already well established in the film industry; however there is still room for
experimentation in the music, multimedia, and broadcast industries. It can certainly
be said that the use of surround channels can enhance the sense of depth and space
over conventional stereo.
For example, the ambience and room reflections of a concert hall delivered from the
surround speakers can drastically change the listener's perspective. Imagine the
difference between peering through a window and sitting in a concert hall. Popular
music can often benefit as well from a creative use of the surrounds, whether with
background singers, instruments, or effects. But as with any new tool or effect, it can
be overdone and become tiresome if used to excess. The principle that has served the