Technical Description; Dolby Digital; Dtsan; Thx Ultra - Marantz SR-14EX Service Manual

12. TECHNICAL DESCRIPTION

This product has two DSP ICs, one is for Dolby Digital (AC-3) decoding or DTS (Digital Theater System) decoding, another is
for THX processing.
Multi channel sound is reproduced by connecting with DVD player or LD player.
Also Dolby Pro Logic decode is available to analog audio and PCM digital audio.
Additionally, 96kHz PCM stereo audio playback is possible.
Decoding circuit is consist of 13 ICs (DIR, two DSP, ADC, five DAC, AC-3 RF demodulator, two data separator and CPU).
DOLBY DIGITAL (AC-3)
Dolby Digital delivers six totally separate (discrete) channels of sound. Like Dolby Surround Pro Logic, it includes Left, Center
and Right channels across the front of the room. Dolby Surround Pro Logic provides a single limited-bandwidth (100 Hz to
7,000 Hz) surround channel which is typically played back in the home through two channels of amplification and two speakers.
In comparison, Dolby Digital provides separate (discrete) left surround and right surround channels, for more precise localiza-
tion of sounds and a more convincing, realistic ambience. And, with Dolby Digital, all five main channels are full range (3 Hz to
20,000 Hz). A subwoofer could be added to each channel, if desired.
The sixth channel, the Low Frequency Effects Channel, will, at times, contain additional bass information to maximize the
impact of scenes such as explosions, crashes, etc. Because this channel has only a limited frequency response (3 Hz to 120
Hz), it is sometimes referred to as the ".1" channel. When added to the 5 full range channels, the Dolby Digital system is
sometimes referred to as having "5.1" channels.
DTS
An amazing new technology for surround-sound entertainment, DTS Digital Surround is an encode/decode system that deliv-
ers six channels (5.1) of master-quality, 20-bit audio. In the encoding process, the DTS algorithm encrypts six channels of 20-
bit digital audio information in the space previously allotted for only two channels of 16-bit linear PCM. Then during playback,
the DTS decoder reconstructs the original six channels of 20-bit digital audio. Each of these six channels is audibly superior to
the 16-bit linear PCM audio found on conventional compact discs.

THX ULTRA

Home THX Controller Technologies : Dubbing stages (where soundtracks are created) and movie theatres do not change their
acoustics, equipment, or system equalization when mixing or playing back 5.1 channel sound tracks. They merely divide the
surround array of speakers into two symmetrical arrays (hence the term "split surround"). All of the remaining system equaliza-
tion and setup remains the same. The Home THX Technologies of Re-Equalization, Timbre Matching, and Decorrelation, as
well as the Home THX Crossover are still necessary for 5.1 channel formats. Because of the nature of the split surround
soundtrack, Home THX Timbre Matching and Decorrelation technologies have been altered to provide correct surround sound
balance and spaciousness. Here is a representation of how Home THX Controller Technologies work with the various surround
sound formats.
THX SURROUND EX
THX Surround EX - Dolby Digital Surround EX is a joint development of Dolby Laboratories and the THX division of Lucasfilm
Ltd.
In a movie theater, film soundtracks that have been encoded with Dolby Digital Surround EX technology are able to reproduce
an extra channel which has been added during the mixing of the program.
This channel, called Surround Back, places sounds behind the listener in addition to the currently available front left, front
center, front right, surround right, surround left and subwoofer channels.
This additional channel provides the opportunity for more detailed imaging behind the listener and brings more depth, spacious
ambience and sound localization than ever before.
Movies that were created using the Dolby Digital Surround EX technology when released into the home consumer market may
exhibit a Dolby Digital Surround EX logo on the packaging.
A list of movies created using this technology can be found on the Dolby web site at
http ://www.dolby.com.
"SURROUND EX ™" is a trademark of Dolby Laboratories. Used under authorization.
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