BowersWilkins CM1 CM2 Owners Manual

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r ntroducing B&w Concept 90

Design Philosophy

Music lovers are as likely as anyone aloe to live in mlllah
houseaor flats-andprobablyrethermorelikeiytohaveen
Appreciation of good design Hitherto. such limited living
space has IW frustrating restrictions on the enloyment
of recorded music: becauae until now it has been virtually
lmooaeibie to mcmate full. occur sound without installing
loudspeakers of unacceptable sue.

Thie challenging question oi how to get the musical
quart into the domestic pint pot has occupied BGWfor some
years in fact. the basic design philo-oohy for Conctpt 90 wee
conceived back in I984. when designer Kenneth Grange
presented iii-ideas for a smell. elegant enclosure -tatally at
home in such limited roomecapea at the small aitting room.
study. dining area or studio apartment.

TharutatothelngenuityofdieBGWdaeignteamd'Iat
concept is now an exciting reality in which you will there
through your purchase oi a 36M! Concept 90 system

BGW Matrix Construction

The 'M in the model name CMl indicates that the loud-
speakers are oi 88W Matrix construction. incorporating the
recent invenflon that eliminates unwanted cabinet vibrations
and brings you all the advantage. oflow enclosure radiation

Although email dimeneiona bring Mi advantages in
the middle and high irequencies. problems ariae from the
conflicting needa of output and low iroquency man-ion.
Within the restraints imposed by the very compact axtarnal
dimenalons that are the raison d'etra of Concept 90. added
wall thickness would have reduced CM! 5 internal volume
unacceptably (conventional constmction materials called
ior wall thickness of IS to lSmmJ Not for the first time.
38W engineers sought a new material and finally chose a
ilbre-relniorcad polymeric board. Thi- ailowo a considerable
reduction in wall thickness - therefore a valuable gain in
internal volume. It took this major advance. combined with
all saw: computer optimlaation expertise, to produce in CNN
a system whoae ban output so belies its diminutive size.

You Will find that thi- il a Iyatem of true monitor quality.
capable oi surprisingly high aound level: Also. thanks to its
made and balanced frequency response. your Concept 90 CMl
will faithfully moroduca even the most delicate nuances of
solo inatrumentollato Overall. it responds splendidly to the
wide dynamic range oi todayu compact disc players. Just as
it wee designed to do

CMZ - extended bass. higher power capacity

In Concept 90. we have not overlooked the requirement: of
those audiophile: whose Intercom demand further extension
of bass response and greater power handling capacity.

For them we haveproduced BWConcaptDOln its CMZ form.
which provides an extra octave-and-a-haif of low frequency
extension beyond thatofthe CMl. Conseoueritiy. model CMZ
faithfully recreates the sound of double bass. bass drum and
tho organist: deepest note! in all their full weight and
splendour.

Thie generoua extension in bass reaponle and incroaao
in power-handling were achieved within the Conceot 90 design
philosophy oi acoustic performance uncompromiaad by
enclosure elegance. It was done by designing the CMZ bass
units into the Wk oi the enclosure. Became of the low
crossover frequency used. Discontinuation in no way impairs
performance and it results in a desirably omnidirectional
pattern of sound radiation

Getting the best from your system

The purpose of this manual is to enhance your enioyment of
the Concept 90 loudspeakers you have amen. A system of
Woman class isstilldependentonthe slgnaisiedintn Itand
is also influenced by the immediate environment in which it
operates Useful acNiceonthase aspect: wrllbelound in the
following page;

An international network ofcareiully chosen Distributors
handles BEWproducbein morethaniortycountriesworidmde.
if at any time you have a problem that your Dealer cannot
"solve. BaWDistrlbutoripryourareamllbemora than
will Ing lio help

Thank you lot the confidence you have shown in
purchasing your Concept 90 loudspeakers Please be assured
of our continuing interest In your long-term lbtening pleasure.

')

l4

; " ' 5W Concept 90 -

H IIT design background

The encloaure: CMl

Following the development and worldwide success oi ma
Matrix series and with Concept 90! basic requirement oi
compectnees always in mind. the SW deaign team seized
the morn-Inky to take Matrix construction one important
step turther by moulding the Civil enclosure and matrix in
one place. uaing glen-fibre relniorcad polyester (- matariai
that is bum acoustically deelrable and exceptionally rigid)
This new construction permits enclosure wall thickness
to be reduced from the usual 15mm to only 5mm. thus allowing
a gain of 46% lntarnal volume. with a cor-aeguent extension
of the low iroquanclee by about third oian octava. Tb thi-
advantage one must add the acknowledged benefitsoi Matrix
construction:
(a) Significant reduction oi those unwanted colourations
so frequently aslociatld with box-type mama
(Any radiation from an enclosure add: its own character
to the desirable neutral. uncoloured sound produced by
the drive units)
Reduction of the decay time of enclosure vibrations.
with consequent imminent in transient footloose -
a key factor in correct reproduction of compact dim
(c) improved detail and depth in the stereo image. due to
reduction of image-confining rear and Sideways
radiation The sounds seem to be in the space around
and betweantheapeekera-not emanating from them

(b)

The enclosure: C M2
Because the columnar sub-bass module ofthe CMZ is small.
and not mulrod to reproduce anything above lSO Hz. it
Incorporates semi ~Matrur construction - la the spacing with-n
the matrix reinforcement is greater man usual. Thit hea proved
more than adequata to ensure that wanted enclosure
radiation us not a) a very low level indeed.

The CMZ employs reilex loadingofthadnvers. Computar
modelling ensures optimisation of output and bauextansion

The drive units: CM!
Reducing enclosure radiation to such extremaly low levels
can give rise toan unfortunate aide effect: the exposure of
hitherto inaudible defects in driver performance. it was
thereiore necessary to carry through a programme ofdriver
development refining unit performances to meet the exacting
demanded the new Matrix tachnologyi

The resulting mourn-orange driver has a cone oi mil
Kevlar. similar to that used in the renowned BS-W studio
monitor;

The high Whey transduceris of entirely new design.
incorporating a metal-domed diaphragm. it exhibits perfect

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