Glossary - T+A DD 820 M User Manual

AV source device
A source device which supplies sound and picture
signals. The sound signals may be generated in
analogue or digital form.
Center
Front loudspeaker between the two main speakers,
located below or directly adjacent to the TV set.
dB
The unit of measurement for electrical levels is the
deciBel (dB).
DSP (Digitaler Signal Processor)
The digital surround
programmable signal processor. A DSP can process
signals using a program stored in the program memory.
The program can be updated at any time, which means
that the decoder can be kept abreast of new
developments.
Front-speaker
Front pair of main loudspeakers, set up to left and right
of the television set.
M
LINK
All the components of a  M-system communicate
with each other via this control interface. Power is also
supplied to the source devices through this interface.
Surround-speaker
Rear pair of loudspeakers, set up behind the listening
position, designed to provide spatial sound effects.
SCART
Widely used standardised connection using a 21-pin
connector. SCART leads can transfer all picture norms
and additional control signals (e. g. for 4:3 / 16:9 picture
format switching). Adaptors are available in specialist
shops for connecting a SCART socket to other standard
connectors (Cinch or Hosiden).
Subwoofer
Loudspeaker designed for reproducing low bass signals.
It is used for special deep bass effects which are
encoded on the LFE channel in Dolby Digital and dts
material. When combined with small satellite speakers
they also provide a full-range bass response.

Glossary

decoder employs a
Surround
General information:
As we all know, a normal stereo recording has two
channels - left and right. When stereo material is
reproduced in your listening room, the entire sound event
takes place on an imaginary stage which covers the space
between the two loudspeakers. The listener is able to
locate specific sound events over the width of the stage;
with good recordings there is also a slight impression of
depth, i. e. behind the speakers. Nevertheless, normal
stereophonic reproduction always leaves the listener
isolated from the event.
As a result it is impossible to recreate the excitement of a
live atmosphere, as in a real concert hall, since the
acoustics of the concert hall are crucially influenced by
sound reflections from the side and back walls, the floor,
the ceiling, and from objects inside the building. The
reflected sound comes from any number of directions - not
just from the front.
If a sound event is to be reproduced with real fidelity, it
fully
therefore follows that a proportion of the sound must
emanate from all directions in the room, that the
"reflections" must be timed accurately, and that they must
be generated at a realistic level.
Reproducing television sound via a conventional stereo
system is problematic, because it is often impossible to
locate dialogue on the screen itself.
A further point is that exotic sound effects have been in
use in the cinema since the 1950's, using proper multi-
channel sound systems. These effects are often crucial to
the overall impact of a film, but they cannot be reproduced
at home with a conventional stereo sound system.
Over the last few years surround technologies have been
developed which make it possible to experience all these
effects within the listener's own four walls, with the result
that a far greater simulation of reality is possible than with
conventional stereo.
For an effective surround system we always recommend
the installation of a center loudspeaker, which is installed
below or directly above the TV set. This loudspeaker helps
greatly in locating particular sound events (especially
dialogue) on the TV screen itself.
Dolby ProLogic II Surround
In this process serveral independent signal channels (left,
center, right, surround (rear) left and surround (rear) right)
are recorded using two channels and a special encoding
process. Since this process only requires two recording
channels, it is compatible with many picture / sound
systems which are already widely in use (CD, video
recorder, TV etc.).
The information is decoded at playback time and
reproduced in the listening room via four (left, right, 2 x
rear) loudspeakers, although five speakers (with an
additional front center speaker) are preferable. Dolby
Surround encoded material is currently available mainly in
the film and video arena, recorded on video cassettes and
DVDs, but a large number of television programmes are
now being produced and transmitted using Dolby
Surround.
64