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16 ADDITIONAL INFORMATION
Optimum surround sound for different sources
There are currently various types of multi-channel signals (signals or formats with more than two channels).
2
Types of multi-channel signals
Dolby Digital, Dolby Pro Logic, DTS, high definition 3-1 signals (Japan MUSE Hi-Vision audio), DVD-Audio, SACD (Super Audio CD), MPEG multi-
channel audio, etc.
“Source” here does not refer to the type of signal (format) but the recorded content. Sources can be divided into two major categories.
2
Types of sources
•
Movie audio
Signals created to be played in movie theaters. In general sound is recorded to be played in movie theaters equipped
with multiple surround speakers, regardless of the format (Dolby Digital, DTS, etc.).
FL
C
SW
FR
FL
C
SW
FR
SL
SR
SB
SL
SR
SB
Multiple surround speakers
Movie theater sound field
Listening room sound field
In this case it is important to achieve the same sense of
expansion as in a movie theater with the surround channels.
To do so, in some cases the number of surround speakers is
increased (to four or eight) or speakers with bipolar or dipolar
properties are used.
•
Other types of audio
These signals are designed to recreate a 360° sound field using three to five speakers.
In this case the speakers should surround the listener from all sides to create a uniform sound
field from 360°. Ideally the surround speakers should function as “point” sound sources in the
same way as the front speakers.
FL
C
SW
FR
SL
SR
These two types of sources thus have different properties, and different speaker settings, particularly for the surround speakers, are required
in order to achieve the ideal sound.
SL: Surround L channel
SR: Surround R channel
SB: Surround back channel
(For 6.1-channel system)
