Yamaha pmn - Manual (Page 103)

E-
97
SOUND FIELD
PR
OGRAMS
English
DIGITAL SOUND FIELD PROCESSING (DSP)
Recreating a sound field
Recreating the sound field of a concert hall or an opera house requires localizing the
virtual sound sources in your listening room. The traditional stereo system that uses only
two speakers is not capable of recreating a realistic sound field. Yamaha’s DSP requires
four effect speakers to recreate sound fields based on the measured sound field data. The
processor controls the strength and delay time of the signals output from the four effect
speakers to localize the virtual sound sources in a full circle around the listener.
The DSP sound field programs can be classified in two types based on the sound field
processing method: programs that use early reflections only and programs that use both
early reflections and reverberation.
Illustration of the virtual sound sources and echo patterns
The virtual sound sources and echo patterns for the DSP sound field programs are shown below. The illustration of the virtual sound sources
shows early reflection sound only and the illustration of the echo patterns shows both reflected sound and reverberation.
■ Virtual sound sources
■ Echo patterns
RL
FR
RR
FL
The center of these circles represent the
virtual sound source.
The size of the circle indicates the strength of
the virtual sound source.
The direct sound source
The listening position
Direct sound source
Early reflections Reverberation
50 – 80 msec