Yamaha YRS-2500 Owner's Manual page 136

APPENDIX
Basic Knowledge of Surround Sound
What is Surround Sound?
Surround sound offers the sense of being surrounded by sounds, an
experience common in concert halls and movie theaters. This can be
achieved by surrounding the audience with numerous speakers from
which sound is output uniformly in all directions. This "surround
sound" technology immerses the listener in sound with speakers
positioned not only in front of the listener, but also behind and to the
sides of the listener, making him or her feel as if they are actually in
the situation.
For precise directional control and quality of sound reproduction,
sounds must be split into separate audio channels for output to each
speaker. Surround sound systems for regular home use (7.1-channel
speaker systems) produce surround sound using seven speakers
and a subwoofer, as shown below:
Typical 7.1 channel speaker system
Subwoofer
Center
speaker
Surround speakers
Surround back speakers
As explained above, sounds can be reproduced for a great sense of
presence by installing multiple speakers. However, this can be
difficult to do in a living room. This unit utilizes "digital sound
projector" technology to provide a realistic and engaging surround
sound experience using only this unit.
What is a Digital Sound Projector?
A digital sound projector separately controls compact speakers
installed in orderly rows, so that optimized audio signals are output
from each speaker and synthesized as highly focused sounds
(sound beams).
Front speakers
When these focused sounds hit a hard wall, they are reflected off of
the wall. A digital sound projector outputs sound beams from five
channels, including front (left/right), center, and surround (left/right)
channels, by reflecting these beams off of walls so that sounds reach
the listener from the appropriate direction. It features a technology
that enables true surround sound without requiring the installation of
speakers in front of, or behind, the listener.
By combining front and surround channel signals, it can also create
two new channels, for a total of seven, so that all channels work
together more closely for a better surround sound experience.
The sound image of the system
Yamaha's Audio Technologies
This unit features many more functions based on Yamaha's superior
audio technologies.
Compressed Music Enhancer
This technology enhances and extends bass and treble, which tend
Digital amplifier
to be weak in digitally compressed formats such as MP3 used with
portable digital audio players and computers. This makes
compressed audio sound more musically dynamic.
Speaker
CINEMA DSP
This technology enables precise digital recreation of actual acoustic
environments found in well-known concert halls and movie theaters.
Sound beams are emitted
This is achieved using Yamaha's exclusive sound field programs,
in the target direction
which are based on data measured in various sound fields, and with
which the amplitude, depth, and volume of sounds have been
adjusted.
Virtual Surround Headphones
These headphones are used to virtually reproduce sound fields. They
provide a more natural and full surround sound experience.
Basic Knowledge of Surround Sound
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