Bowers & Wilkins CM4 Portable Speaker User Manual


 
English
Limited Warranty
Dear customer,
Welcome to B&W.
This product has been designed and
manufactured to the highest quality
standards. However, if something does go
wrong with this product, B&W
Loudspeakers and its national distributors
warrant free of charge labour (exclusion
may apply) and replacement parts in any
country served by an official B&W
distributor.
This limited warranty is valid for a period of
five years from the date of purchase or two
years for electronics including amplified
loudspeakers.
Terms and Conditions
1 The warranty is limited to the repair of
the equipment. Neither transportation,
nor any other costs, nor any risk for
removal, transportation and installation
of products is covered by this warranty.
2 This warranty is only valid for the
original owner. It is not transferable.
3 This warranty will not be applicable in
cases other than defects in materials
and/or workmanship at the time of
purchase and will not be applicable:
a. for damages caused by incorrect
installation, connection or packing,
b. for damages caused by any use other
than correct use described in the user
manual, negligence, modifications, or
use of parts that are not made or
authorised by B&W,
c. for damages caused by faulty or
unsuitable ancillary equipment,
d. for damages caused by accidents,
lightning, water, fire heat, war, public
disturbances or any other cause
beyond the reasonable control of B&W
and its appointed distributors,
e. for products whose serial number has
been altered, deleted, removed or
made illegible,
f. if repairs or modifications have been
executed by an unauthorised person.
4 This guarantee complements any
national/regional law obligations of
dealers or national distributors and
does not affect your statutory rights as
a customer.
How to claim repairs under
warranty
Should service be required, please follow
the following procedure:
1 If the equipment is being used in the
country of purchase, you should
contact the B&W authorised dealer
from whom the equipment was
purchased.
2 If the equipment is being used outside
the country of purchase, you should
contact B&W national distributor in the
country of residence who will advise
where the equipment can be serviced.
You can call B&W in the UK or visit our
web site to get the contact details of
your local distributor.
To validate your warranty, you will need to
produce this warranty booklet completed
and stamped by your dealer on the date of
purchase. Alternatively, you will need the
original sales invoice or other proof of
ownership and date of purchase.
Owner’s manual
Introduction
Thank you for choosing B&W.
Please read this manual fully before
unpacking and installing the product. It will
help you to optimise its performance.
B&W maintains a network of dedicated
distributors in over 60 countries who will be
able to help you should you have any
problems your dealer cannot resolve.
Unpacking (Figure 1)
Fold the top carton flaps right back and
invert the carton and contents.
Lift the carton clear of the contents.
Remove the inner packing from the
product.
We suggest you retain the packing for
future use.
Check in the carton for:
4 Spike feet with lock nuts
2 Foam bungs
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Connections (Figure 2 & 3)
All connections should be made with the
equipment switched off.
There are 2 pairs of terminals at the back of
the speaker which permit bi-wiring if
desired. On delivery, the separate pairs are
connected together with high-quality links
for use with a single 2-core cable. For
single cable connection, leave the links in
place and use either pair of terminals on
the speaker.
Ensure the positive terminal on the speaker
(marked + and coloured red) is connected
to the positive output terminal of the
amplifier and negative (marked – and
coloured black) to negative. Incorrect
connection can result in poor imaging and
loss of bass.
To bi-wire, remove the links by loosening
the terminal caps and use a separate
2-core cable from the amplifier to each pair
of terminals. This can improve the
resolution of low-frequency detail. Observe
the correct polarity as before. When bi-
wiring, incorrect connection can also impair
the frequency response.
The terminals accept bare wire. Always
make sure terminals are screwed down
tight as otherwise they may rattle.
Ask your dealer for advice when choosing
cable. Keep the total impedance below the
maximum recommended in specification
and use a low inductance cable to avoid
attenuation of the highest frequencies.
Positioning (Figure 4)
Some experimentation with the position of
the speakers is well worthwhile to optimise
the interaction between them and the
listening room.
However, as an initial guide:
Do not fit the spike feet until you have
found the best position for the speakers.
Place the speakers and the centre of the
listening area approximately at the
corners of an equilateral triangle.
Keep the speakers at least 1.5m (5ft)
apart to maintain left-right stereo
separation.
Keep the speaker baffles at least 0.5m
(20in) clear of walls. Having the speakers
too close to walls increases the level of
bass relative to midrange and may give a
boomy quality to the sound.
Stray magnetic fields
The speaker drive units create stray
magnetic fields that extend beyond the
boundaries of the cabinet. We recommend
you keep magnetically sensitive articles
(television and computer screens, computer
discs, audio and video tapes, swipe cards
and the like) at least 0.5m from the
speaker.
Fine tuning
Before fine tuning, make sure that all the
connections in the installation are correct
and secure.
If the level bass is uneven with frequency it
is usually due to the excitation of
resonance modes in the room. Even small
changes in the position of the speakers or
the listeners can have a profound effect on
how these resonances affect the sound. Try
mounting the speakers along a different
wall. Even large pieces of furniture can
have an effect.
Moving the speakers further from the walls
will reduce the general level of bass. Space
behind the speakers also helps to create an
impression of depth. Conversely, moving
the speakers closer to the walls will
increase the level of bass.
If you want to reduce the bass level without
moving the speakers further from the wall,
fit the foam bungs in the port tubes.
(Figure 6)
If the central image is poor, try moving the
speakers closer together or toeing them in
so they point just in front of the listeners.
(Figure 5)
If the sound is too harsh, increase the
amount of soft furnishings in the room (for
example use heavier curtains), or reduce it
if the sound is dull and lifeless.
Test for flutter echoes by clapping your
hands and listening for rapid repetitions.
Reduce them by the use of irregular
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