· CEM Power Edition
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Active subwoofer
Speaker for bass playback, with integrated am-
plifier. Very low frequencies can be only repro-
duced by a large-scale speaker. In order for the
main speakers to stay as compact as possible,
a separate subwoofer is used for bass tones. It
can be located unobtrusively in the living room:
for instance, behind the sofa or under a side
table. The cut-off frequency between the main
speakers and the subwoofer depends on the
components used, but is usually between 50 and
120 hertz.
Auto on/off function
The Auto on/off function switches the subwoofer
on as soon as a signal is detected and off again
a certain time after the last signal was trans-
ferred (around 20 minutes).
Centre
Central speaker in the home cinema system. All
dialogues are played back via the centre. There-
fore, good voice playback capability is essential
for the centre.
Direct emitters
Direct emitters are all conventional speaker
boxes that have been set up so that they emit
sound towards the listener in a straight line. In
a home cinema, direct emitters are mainly used
for the three front channels, in concert sets and
in the rear area.
Dolby Digital/DTS decoder
Electronic switch for splitting the digital signal
from the DVD into up to 7 individual analogue
signals. Dolby Digital and DTS are two differ-
ent sound formats, so two different decoders
are also required. AV receivers, DVD players or
corresponding sound cards usually have both
decoders.
Frequency/cut-off frequency
You can use the cut-off frequency to determine
the frequency level at which playback stops com-
ing from the subwoofer and starts coming from
the satellites. If, for example, you set a cut-off
frequency of 120 Hz, all frequencies above 120 Hz
are emitted by the satellites, frequencies under
120 Hz are played by the subwoofer.
Level
The level controller on the subwoofer is used
to adjust the volume. For perfect playback, all
speaker channels – incl. the subwoofer – should
be set such that the signals from the individual
speakers can be heard equally loudly at the
listening location.
Phase
With the phase controller, you can adjust the
subwoofer to the satellites such that the
speaker membranes vibrate in the same direction
in the cut-off frequency range. If the phase is
set incorrectly, the bass may be weakened or
cancelled. If the subwoofer is located between
the front speakers we recommend 0°, for a posi-
tion close to the listening location 180°. If the
subwoofer is in another location, the “180°” set-
ting can balance out the reduced bass playback.
Set the phase controller appropriately to get the
strongest bass playback.
Sub out
Output on the receiver/amplifier to connect an
active subwoofer using a mono-cinch cable.
Surround speaker
Effects and atmospheric sounds are reproduced
through the surround speakers. This gives a
greater spatial feel when playing back films and
music.
5 .1/7 .1 pre out
Pre-amplifier output on the receiver or out-
put on the DVD player. One analogue signal is
provided for each speaker channel via cinch
connection.
6 .1/7 .1 technology
Surround sound process with one or two rear
centre speakers between the lateral rear effect
speakers. The additional rear centre signal
(compared with 5.1 systems) is created from the
stereo rear effects signals (e.g. THX
®
Surround
EX, Dolby Digital EX) or comes from a separate
dedicated channel (DTS Discrete). Although only
one channel has been added, you have the option
of connecting one (6.1 technology) or two (7.1
technology) rear centres. That is why we talk
about 7.1-channel sound, even though the sound
format is 6.1-channel.
Home cinema glossary
