Bowers & Wilkins Custom Theatre SA1000 Manuel D'installation Et De Configuration page 8

be set and the less hard the subwoofer has to work;
but there is a down side. Subwoofers positioned near
corners often generate more low-frequency room
resonances, making the bass more uneven with
frequency. There is no substitute for experiment as all
rooms behave differently, so the subwoofer should be
tried in a variety of positions before a final decision is
made. A piece of music with a bass line ascending or
descending the musical scale is useful for assessing
the smoothness of the bass response. Listen for
exaggerated or quiet notes.
Using multiple subwoofers in a single installation can
improve performance in the following ways:
• Maintains stereo separation to the lowest
frequencies.
• Smooth out the effects of low frequency room
resonances.
• Enable a higher maximum sound output.
In the case of two subwoofers used in a 2-channel
audio system, stereo separation will only be improved
if each channel has its own subwoofer located close
to the appropriate satellite speaker.
Stray Magnetic Fields
The subwoofer drive units create stray magnetic fields
that extend beyond the boundaries of the cabinet. We
recommend you keep magnetically sensitive articles
(CRT television and computer screens, computer
discs, audio and video tapes, swipe cards and the
like) at least 0.5m (20 in) from the speaker. LCD and
plasma screens are not affected by magnetic fields.
Grilles
The CT SW Series subwoofers are fitted with
magnetically attached fabric grilles which may be
removed if desired. Take care not to damage the drive
units when removing or replacing the grilles.
Subwoofer Amplifier Installation
The SA1000 subwoofer amplifier is intended to be
installed in standard 19 inch equipment racks. It is
supplied with rack-mount ears but rack mount bolts
and nuts are not supplied. Ensure that, once mounted
in the rack, the amplifier is well ventilated and that its
ventilation apertures are not obstructed.
Rack Mounting the SA1000
The SA1000 is supplied with two rack mounting
brackets for installation in standard equipment racks.
To install these brackets:
Install the rack mount bracket, inserting three of the
small Philips head machine screws through the
bracket and the threaded holes in the side of the
amplifier.
Repeat for the bracket on the other side of the
amplifier.
SA1000 Rack Handles
The rack mount brackets are supplied with handles,
which can be installed or removed. The handles are
installed with two of the long Philips head machine
screws inserted through the rack mount bracket and
into the threaded holes in the handles. If you do not
use the handles, use the rubber hole plugs supplied
with the bracket hardware to fill the exposed holes.
Subwoofer Amplifier Internal EQ Jumper
Settings
The SA1000 subwoofer amplifier is fitted with internal
jumper settings to provide additional fine tuning for the
amplifier for the specific CT subwoofer it will be
driving. These jumpers are only accessible by
removing the amplifier lid (see figure 5) and as such
this must only be undertaken by qualified service
personnel.
Subwoofer Amplifier Connections
The SA1000 subwoofer amplifier is fitted with a variety
of connection sockets on its rear panel:
1 x Mains input socket: Connect mains power using
the appropriate cable for your territory.
1 x Neutrik Speakon Output Socket: A four-pole
Speakon enabling connection of one or two (identical)
subwoofers. Speakon sockets provide a more secure
and reliable connection than bare-wire or 4mm
sockets.
4 x Binding Posts Outputs: Two pairs of binding posts
provide alternative bare-wire or 4mm socket
connection for one or two (identical) subwoofers.
1 x RCA Phono Input: Input socket for connection to
an AV processor or preamplifier subwoofer output.
1 x XLR Input: Alternative balanced input socket for
connection to an AV processor or preamplifier
subwoofer output.
1 x RCA Phono Output: Output socket for connection
to the input of a second subwoofer amplifier.
1 x XLR Output: Alternative balanced output socket for
connection to the input of a second subwoofer amplifier.
2 x 3.5mm Jack Trigger Inputs: 12V trigger inputs to
enable automated control of amplifier standby and
movie/music function selection.
Connecting the subwoofer amplifier to the subwoofer,
including the use of Speakon plugs, is covered in the
Connecting Sections below.
Subwoofer Amplifier Controls
The SA1000 subwoofer amplifier front panel carries
the following controls.
Volume: Sets the overall volume of the subwoofer.
Filter: Sets the low-pass cut-off frequency of the
subwoofer filter.
Low-pass In/Out: Engages or defeats the subwoofer
filter.
Phase: Reverses the subwoofer output phase.
Bass Extension: Provides three bass extension
options.
Movie/Music EQ: Provides equalisation options for
music or movie programme material.
On/Auto/Standby: Provides switch-on and standby
options.
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