7.1 channel
Position two speakers to the sides in line
with the centre of the listening area and
two behind the listeners, subtending an
angle of approximately 40ยบ. (figure 6)
PREPARING THE LOCATIONChoosing cable
Excessive resistance in the speaker cable
wastes power and alters the frequency
response of the speaker. Always try to keep
the resistance as low as possible with the
loop resistance preferably below 0.5 ohms
for non-critical applications and below
0.2ohms for best results. Use the table of
figure 10 to calculate the minimum gauge
of cable required.
Existing drywall construction(retrofit)
Mark the centre position of the speaker and
position the template so the mark shows
through the hole in the middle.
Trace round the outer edge of the template
and cut neatly just inside the line.
To improve the mechanical integrity of the
ceiling or wall and reduce the likelihood of
rattles, we recommend you apply a bead of
wood glue or mastic along the joints
between the back of the plasterboard and
the studs in the vicinity if the speaker.
Run the cable to the aperture, allowing
enough length to comfortably connect the
speaker, but not too much, as the excess
may rattle against the structure.
New drywall construction
The speaker can be installed once the
ceiling or wall is completed in the same
manner as retrofitting, but it is easier to
position and cut the hole if the optional pre-
mount kit is used before the plasterboard
(sheetrock) is fitted.
Staple or nail the PMK to the studs as
described in the instructions with the kit.
Run the cable and secure it to the fixing
point on the PMK. Allow enough length to
comfortably connect the speaker, but not
too much, as the excess may rattle against
the structure.
Results are affected by how well the
plasterboard is attached to the studs and
we recommend gluing as well as screwing
or nailing the panels to the studs in the
vicinity of the speaker.
Once the board is fitted, the inner flange of
the PMK serves as a guide for a hole router
or saw.
Solid wall construction
In order for the bass performance not to be
compromised, the speaker requires a cavity
volume of at least 15 litres. This means that,
in a standard 10cm (4 in) thick wall, the
cavity will extend beyond the boundaries of
the speaker frame. It is possible to provide
this cavity simply by using a lintel, covering
the hole with plasterboard and fitting the
speaker as described above for retrofitting
into a drywall. (figure 7)
Damping the cavity
Fill the wall cavity, allowing room for the
speaker itself, with unlined fibreglass or
mineral wool matting. The packing density
should be just enough to comfortably
prevent the material from dropping or
sagging over time. In an open wall cavity, fill
to a distance of at least 30cm (1 ft) above
and below the speaker. (figure 8)
In the ceiling, drape the matting at the back
of the ceiling board, covering the aperture
and extending at least 30cm (1 ft) around
the speaker into open void.
IMPORTANT: Ensure that the materials you
use meet local fire and safety regulations.
Fitting the speaker
All connections should be made with the
equipment switched off.
Connect the cable, observing the correct
polarity.
With the grille removed, position the
speaker in the aperture and screw in the
4screws visible from the front. (figure 9)
These screws automatically swing out
clamping dogs that locate behind the
mounting surface. Ensure that they have
located properly before fully tightening the
screws. A certain amount of flexing of the
frame is allowed to take up unevenness in
the mounting surface, but do not over-
tighten the screws as excessive distortion
of the speaker frame may result.
Adjusting the speaker
The speaker is designed to point towards
the listening area and for most instances
this gives best results. However, for some
surround speaker applications, better
overall results may be obtained if the sound
is directed away from the listening area.
Typically this may apply if:
a. The room is particularly live and the
sound becomes harsh.
b. The listening area is a large proportion
of the room. Increasing the amount of
reflected sound and reducing the
amount of direct sound may give a
better average balance between the
speakers for all listeners.
Customising
The frame and grille have a paintable white
semi-matte finish, ready if necessary to be
re-finished to match your own decor.
Before painting the grille, remove it from the
frame and peel off the fabric scrim from the
back, otherwise the pores will get clogged
and the sound will be impaired.
When replacing the scrim, first spray the
back of the grille mesh (NOT the scrim)
with a light coating of 3M SprayMount
adhesive or similar. Locate the small V cut
in the scrim and line it up with the V cut in
the edge of the grille mesh. The scrim
should overlap the vertical skirting edge of
the mesh. Smooth out the scrim, working
away from the starting point. Avoid creases
behind the curved profile of the mesh, as
these will show through the grille, but it
does not matter if the scrim folds back up
the vertical skirting edge of the mesh when
you replace it in the frame.
Do not stretch the scrim unduly as it may
relax and pull away from the mesh over
time and cause a buzzing noise.
Do not re-finish the drive units or baffle
area behind the grille. Use the paint mask
provided. Avoid touching the drive units, as
damage may result.
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