_default _132_pages.indd - TELE-satellite International Magazine

preferably with HDMI 1.3 cable. In such
setup, you achieve the best possible
signal quality.
But if you have just Dolby Digital surround
sound decoder, you simply use S/
PDIF cable for connecting both devices
Fig 2. Connecting DD+ and DD compatible A/V receivers to the set-top-box.
stream is repackaged to DD bitstream
and output on S/PDIF connector. Its
bitrate is equal to 640 kbps. It means
that you get better sound than standard
Dolby Digital broadcast audio, which is
limited to 448 kbps.
Popularity and
possible extensions
Dolby Digital Plus has been adopted for
bandwidth in the Internet TV is as important
as in all other forms of digital TV.
The highlights of this format do not
end in better compression ratio and
superior sound quality compared to the
More than 5.1 channels are possible.
Although Dolby Digital Plus for Blu-ray
12 TELE-satellite — Global Digital TV Magazine — 04-05/2010 — www.TELE-satellite.com
Disc is limited to 7.1 channels, generally
in the future, while retaining compatibility
with all Dolby Digital Plus players
channels, the total bitrate required in the
transmission channel need to go up to
4.7 Mbps. The HDMI output peak bitrate
can reach 6.144 Mbps then.
So far 7.1 A/V receivers are rare, but
this is the future of top class audio. Will
they be used only in Blu-ray Discs or
also in digital TV? It is hard to say today.
Presently, the main reason to introduce
Dolby Digital Plus in digital TV is the need
to save the bandwidth. But who knows,
maybe in a year or two, the premium
movie or music channels will start 7.1
channel transmission?
DD+
Audio Channels: 1.0 to 13.1 (i.e. from
mono to 13 full range channels and a low
frequency effects channel)