Chapter 1 introduction, Chapter 1, Introduction – Dolby Laboratories DP572 User Manual
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Dolby E Multichannel Distribution System User Manual
1-1
Chapter 1
Introduction
The Dolby E multichannel distribution system is the first technology that can transport
multichannel audio within the digital broadcast industry’s current two-channel infra-
structure. A single Dolby E bitstream can carry up to eight discrete audio channels,
each with its associated Dolby Digital metadata, in a 16- or 20-bit, 48 kHz AES pair.
Since Dolby E’s audio and video frame rates are identical, many common editing and
switching practices can be performed on the encoded bitstream without causing mutes
or other disturbances in the decoded PCM audio. For editing tasks that require decoding,
Dolby E’s sophisticated audio coding algorithm allows ten or more encode/decode cycles
without audible degradation; this exceeds the requirements of even the most elaborate
program contribution, distribution, and emission paths.
Even experienced studio engineers must learn new techniques and terminology to begin
using these Dolby E devices. Fortunately, Dolby Laboratories has greatly simplified the
process of getting started:
•
The DP571 encoder and DP572 decoder employ an almost identical front-pan-
el user interface. The devices are also similar to some of the Dolby Digital series
of encoders and decoders, which may be familiar to broadcast engineers.
•
Choosing the appropriate Program Configuration on the DP571 is logically
connected to the application type. Selecting the Program Config sets most of
the DP571 encoding parameters including the Dolby Digital metadata. Very
few, if any, individual parameters need to be set.
•
The DP572 decoder is almost entirely configured by the settings in the encoded
Dolby E stream from the DP571.
We included both devices in one manual because they will almost always be used in the
same system. This manual is organized to emphasize the similarities between the encoder
and decoder, and to enable engineers with different learning styles access to the material
in the manner they prefer.