Bowers & Wilkins Signature 7NT, Installation Manual

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either directly above or directly below the screen. All
other things being equal, choose the position that is
nearest ear height. However, if this leads to a below
screen position, you should be careful to ensure that
the speaker is not too close to the floor (see above)
and that the sound will not be muffled by the later
placement of furniture. See also the comments on
baffle orientation in the preceding section.
Home Theatre Surround Speaker
Applications
The sound from surround speakers should be as
diffuse as possible. This ensures that the frontal audio
image is not distorted by changes of listener position
or head movements. The speakers should generally be
placed behind and 0.6m (2ft) or more above ear
height. Ceiling mounting often gives good results in
this application. The orientation is less important in
this application than in other cases.
WARNING: The Signature™7NT speakers produce a
static magnetic field that extends outside the speakers
boundary. As such they should not be placed within
0.5m (20in) of equipment that may be affected by
such a field, e.g. Cathode Ray Tubes in TVs and
Personal Computers. LCD and plasma screens are not
affected by magnetic fields.
Damping the wall cavity
A foam pad is supplied to damp the area behind the
drive units. In addition, loosely fill the whole section of
the wall cavity with wadding. Fibreglass and mineral
wool matting supplied for heat insulation are suitable,
but not closed cell foam or expanded polystyrene.
Check that there is no debris that may fall into the
speaker (especially in ceiling mount situations).
IMPORTANT: YOU SHOULD CHECK THAT THE
INSTALLATION ITSELF AND THE MATERIALS YOU
USE MEET THE LOCAL FIRE AND BUILDING
REGULATIONS.
Fitting the wall frame
New Construction (figure 3)
Fit the separately available pre-mount kit PMK W8 for
the Signature™7NT to the studding before the drywall
panels are fitted, following the instructions supplied
with the kit. The drywall panels should be fitted up to
the pre-mount frame and plastered over.
Screw, but do not tighten, 4 of the screws provided
through the holes in the wall frame into the pilot holes
in the pre-mount frame.
Existing Construction (figure 4)
Push out the slots in the template provided. Position
the template on the wall as required. Mark along the
inside edges of the slots and cut out the aperture
neatly.
Position the frame in the wall and screw in the
6 screws visible from the front of the frame. These
screws swing out clamping dogs that locate behind
the drywall. Ensure that they have located properly
and loosely tighten the screws.
Existing construction Method 2
Using the pre-mount frame in retrofit situations
requires that the aperture is cut fairly accurately. Use
the template provided to mark out the correct size
aperture, having regard to how the wall frame is to be
lined up with any features such as door frames, and
cut out the aperture neatly. Feed the pre-mount frame
through the aperture and pull it forward so that it sits
flat on the rear of the drywall and the inner part of the
frame protrudes through the aperture. Screw, but do
not tighten, 4 of the screws provided through the slots
in the wall frame into the pilot holes in the pre-mount
frame.
All Methods
Align the frame square with the wall and tighten down
the screws. A certain amount of flexing of the wall
frame is allowed to take up unevenness in the wall
surface, but do not over tighten the screws as
excessive distortion of the frame may impede the
fitting of the baffle.
Customising
The wall frame has a white semi-matte paintable finish,
ready if necessary to be re-finished to match your own
decor. Decorate before the baffle is fitted.
Do not paint the baffle. Remove it before re-decoration.
Avoid touching the drive units, as damage may result.
Fitting the baffle and connections
(figure 5)
All connections should be made with the equipment
switched off.
The baffle is secured to the wall frame by 4 machine
screws in the corners. A pre-fitted gasket seals the
joint.
There are two pairs of gold plated terminals at the
back of each speaker, one pair to the bass/mid unit
and one pair to the tweeter which permit bi-wiring or
bi-amplification if desired. On delivery, both pairs are
connected together by high-quality gold plated copper
links for use with a single twin cable.
The terminals accept bare wires. For single cable
connection, connect either of the positive terminals on
the speaker ( and coloured red) to the
positive terminal on the power amplifier and negative
(-, black) to negative (figure 5).
When bi-wiring the speakers, loosen the terminal caps
and remove the links. Use a separate twin cable from
the amplifier terminals to each pair of speaker
terminals (figure 5). Correct polarity connection is even
more critical in this case to maintain the frequency
response of each speaker as well as the correct
balance between left and right speakers. The use of
separate cables can improve the reproduction of low-
level detail by reducing interaction in the crossover
and allowing optimum choice of cable for each
frequency range.
Always make sure all the terminal caps are screwed
down tight, as otherwise they may rattle. Failure to
observe correct polarity will result in a loss of bass
and vague imaging in a multi-speaker installation.
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