Bowers & Wilkins ASW825: инструкция

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800 Series

ASW825

ASW855

Owner’s Manual

and Warranty

CoverASW825-855.qxd 8/6/05 4:28 pm Page 5

Figure 1

Figure 2

Figure 3

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Figure 4

Figure 5

ASW 825-855 inside 8/6/05 4:35 pm Page 1

Contents

English

Русский

Limited Warranty...........2

Ограниченная

Owner’s Manual............2

гарантия....................38

Руководство по

Français

эксплуатации ............38

Garantie limitée.............6

Manuel d’utilisation.......6

Norsk

Tidsbegrenset

Deutsch

garanti........................43

Beschränkte

Bruksanvisning ...........43

Garantie .....................10

Bedienungsanleitung...11

Svenska

Begränsad garanti ......45

Español

Bruksanvisning ...........45

Garantía limitada.........15

Manual de

Suomi

instrucciones ..............15

Takuuehdot.................46

Omistajan kasikirja......47

Português

Garantia limitada.........20

Manual do utilizador....20

.......................48

.....................48

Italiano

Garanzia limitata .........24

Manuale di istruzioni ...24

.......................52

....................52

Nederlands

Beperkte garantie .......28

Handleiding ................29

.......................55

....................56

Ελληνικά

Περιορισµένη

εγγύηση....................32

Οδηγίεσ Χρήσεωσ ....33

1

ASW 825-855 inside 8/6/05 4:35 pm Page 2

where the equipment can be serviced.

dealer or local power company.

English

Y

ou can call B&W in the UK or visit our

7 Grounding or Polarisation – The

web site to get the contact details of

appliance is not r

equired to be

your local distributor.

Limited Warranty

gr

ounded. Ensure the plug is fully

To validate your warranty, you will need to

inserted into the wall outlet or

Dear customer,

pr

oduce this warranty booklet completed

extension cor

d receptacle to prevent

and stamped by your dealer on the date of

blade or pin exposur

e. Some versions

W

elcome to B&W.

purchase. Alternatively, you will need the

of the product are equipped with a

This pr

oduct has been designed and

original sales invoice or other pr

oof of

power cor

d fitted with a polarised

manufactured to the highest quality

ownership and date of pur

chase.

alter

nating line plug (a plug having one

standards. However, if something does go

blade wider than the other). This plug

wr

ong with this product, B&W

will fit onto the power outlet only one

Loudspeakers and its national distributors

way

. This is a safety feature. If you are

warrant free of charge labour (exclusion

Owner’s manual

unable to insert the plug fully into the

may apply) and r

eplacement parts in any

outlet, try r

eversing the plug. If the plug

country served by an official B&W

should still fail to fit, contact your

distributor

.

electrician to replace your obsolete

IMPORTANT

outlet. Do not defeat the safety

This limited warranty is valid for a period of

purpose of the polarised plug. When

five years fr

om the date of purchase or two

SAFETY

using an extension power-supply cord

years for electronics including amplified

or a power-supply cord other than that

loudspeakers.

INSTRUCTIONS

supplied with the appliance, it should

Terms and Conditions

be fitted with the appropriate moulded-

CAUTION

on plugs and carry safety approval

1

The warranty is limited to the repair of

RISK OF ELECTRIC SHOCK

appropriate to the country of use.

the equipment. Neither transportation,

DO NOT OPEN

nor any other costs, nor any risk for

8 Power Cord Protection – Power-supply

removal, transportation and installation

Caution:

cords should be routed so that they

of pr

oducts is cover

ed by this warranty.

ar

e not likely to be walked on or

To reduce the risk of electric shock, do not

pinched by items placed on or against

2

This warranty is only valid for the

r

emove the back panel and do not expose

them, paying particular attention to

original owner. It is not transferable.

the apparatus to rain or moisture. No user-

cords at plugs, convenience

serviceable parts inside. Refer servicing to

3

This warranty will not be applicable in

receptacles and the point where they

qualified personnel.

cases other than defects in materials

exit from the appliance.

and/or workmanship at the time of

Explanation of Graphical

9 Overloading – Do not overload wall

purchase and will not be applicable:

Symbols:

outlets, extension cords or integral

a

for damages caused by incorrect

convenience r

eceptacles, as this can

The lightning flash within an

installation, connection or packing,

result in a risk of fire or electric shock.

equilateral triangle is intended

b

for damages caused by any use other

to alert you to the presence of

10 Ventilation – The amplifier panel at the

than correct use described in the user

uninsulated “danger

ous

rear of the product forms part of the

manual, negligence, modifications, or

voltage” within the product’s

cooling mechanism and must not be

use of parts that are not made or

enclosure that may be of

obscured by placing the product on a

authorised by B&W,

suf

ficient magnitude to

bed, sofa, rug, or other similar surface.

constitute an electric shock to

Do not cover the amplifier panel with

c for damages caused by faulty or

persons.

any items such as tablecloths,

unsuitable ancillary equipment,

newspapers, etc. Ensure the heat sink

The exclamation point within

d

for damages caused by accidents,

fins are aligned vertically to ensure

an equilateral triangle is

lightning, water, fire heat, war, public

pr

oper cooling. Ther

e should be a clear

intended to alert you to the

disturbances or any other cause

gap of at least 50mm (2-in) between

presence of important

beyond the r

easonable contr

ol of B&W

the back of the pr

oduct and any wall

operating and maintenance

and its appointed distributors,

or partition. If the pr

oduct is placed in

(servicing) instructions in the

a built-in installation, such as a rack,

e for products whose serial number has

literature accompanying the

bookcase or cabinet, pr

oper provision

been altered, deleted, removed or

appliance.

for air to circulate must be provided,

made illegible,

either by a) 12mm (1/2-in) clear gap

WARNINGS:

f if repairs or modifications have been

round the top, sides and bottom of the

executed by an unauthorised person.

1 Read Instructions – All the safety and

pr

oduct venting into the r

oom or b) two

operating instructions should be r

ead

ducts of 150 sq cm (24 sq in) minimum

4 This guarantee complements any

before the appliance is operated.

cr

oss section fr

om the r

oom leading to

national/regional law obligations of

slots 300mm (12-in) wide x 50mm

dealers or national distributors and

2 Retain Instructions – The safety and

(2-in) deep at top and bottom of the

does not af

fect your statutory rights as

operating instructions should be

compartment, in line with the gap

a customer.

retained for future reference.

behind the product.

How to claim repairs under

3 Heed Warnings – All warnings on the

11

Heat – The product should be situated

warranty

appliance and in the operating

away fr

om heat sour

ces such as

instructions should be adher

ed to.

Should service be required, please follow

radiators, heat registers, stoves, or

the following procedure:

4 Follow Instructions – All operating and

other products (including amplifiers)

use instructions should be followed.

that pr

oduce heat. No naked flame

1

If the equipment is being used in the

sources, such as lighted candles,

country of purchase, you should

5 Installation – Install in accordance with

should be placed on the apparatus.

contact the B&W authorised dealer

the manufacturer's instructions.

from whom the equipment was

12 Wall or Ceiling Mounting – The product

6 Power Sources – This product should

pur

chased.

should be mounted to a wall or ceiling

be operated only fr

om the type of

only as recommended by the

2 If the equipment is being used outside

power source indicated by the marking

manufacturer.

the country of purchase, you should

situated on the rear panel. If you are

contact B&W national distributor in the

not sur

e of the type of power supply to

13 Water and Moisture – To reduce the

country of r

esidence who will advise

your home, consult your pr

oduct

risk of fir

e or electric shock, do not

2

ASW 825-855 inside 8/6/05 4:35 pm Page 3

expose the product to rain or

a When the power-supply cord or

ensure that the technology is put to

excessive moistur

e such as in a sauna

plug has been damaged.

maximum ef

fect.

or bathr

oom. Do not use this product

b

If liquid has been spilled or objects

This subwoofer has been designed for

near water – for example, near a

have fallen into the appliance.

Home Theatr

e installations and to augment

bathtub, washbowl, kitchen sink,

the bass performance of full-range

laundry tub, in a wet basement, or

c

If the product has been exposed to

speakers in 2-channel audio use. Adding

near a swimming pool and the like.

rain or water.

the subwoofer to your system not only

14 Object and Liquid Entry – Never push

d If the product does not operate

extends the bass to lower frequencies, it

objects of any kind into this pr

oduct

normally by following the operating

impr

oves the midrange clarity by reducing

thr

ough openings, as they may touch

instructions. Adjust only those

the low-fr

equency demands on your

dangerous voltage points or short out

controls that are covered by the

existing speakers.

parts that could r

esult in a fire or

operating instructions, as an

Please read through this manual fully before

electric shock. Never spill liquid of any

impr

oper adjustment of other

using the subwoofer

. All sound installations

kind on the product. Do not place any

controls may result in damage and

r

equire some planning and experimentation

object containing liquid on top of the

will often r

equire extensive work by

if you are to get the best out of the

pr

oduct.

a qualified technician to r

estore the

products used and this manual will guide

product to its normal operation.

15

Cleaning – Unplug the product from

you in this pr

ocess.

the wall outlet before cleaning. The

e If the product has been dropped, or

As the subwoofer is connected to the

cabinet of the subwoofer may be

damaged in any way.

electricity power supply, it is important that

cleaned by dusting with a dry cloth. If

f When the product exhibits a distinct

you familiarise yourself with the safety

you wish to use an aerosol cleaning

change in performance – this

instructions and heed all warnings.

spray

, do not spray directly on the

indicates a need for service.

cabinet; spray onto the cloth. Remove

Keep this manual in a safe place for future

the grille first so that the cloth does not

22 Replacement Parts – When

reference.

become stained, but be car

eful not to

r

eplacement parts are required, be

B&W products are distributed to over

disturb the drive unit. The grille itself

sure the service technician has used

60

countries worldwide and we maintain an

may be cleaned using a soft brush.

replacement parts specified by the

international network of carefully chosen

manufactur

er or have the same

16 Attachments – Do not use attachments

and dedicated distributors. If you have a

characteristics as the original part.

not recommended by the product

problem, which your dealer cannot resolve,

Unauthorised substitutions may result

manufactur

er

, as they may cause

our distributors will be mor

e than willing to

in fire, electric shock or other hazards.

hazards.

assist you.

17 Accessories – Do not place this

Unpacking

product on an unstable cart, stand,

(figure 1)

tripod, bracket or table. The pr

oduct

may fall, causing serious injury to a

The easiest way to unpack the subwoofer

child or adult, and serious damage to

23 Mains Fuses – For continued

and avoid damage is as follows:

the product. Use only with a cart,

protection against fire hazard, use

• Open the carton flaps right back and

stand, tripod, bracket or table

fuses only of the correct type and

invert the carton and contents.

recommended by the manufacturer or

rating. The amplifier is designed to

sold with the pr

oduct. Any mounting of

operate with nominal mains supplies in

• Lift the carton away from the product.

the product should follow the

the range 100V to 230V AC, but

W

e recommend that you retain the

manufacturer’s instructions and should

different types of fuse are used,

packaging for future use.

use a mounting accessory

dependent on the mains voltage. The

recommended by the manufacturer.

correct fuse specification for each

In addition to this manual, the carton

voltage range is marked on the

should contain:

18 Moving the appliance – A product and

product.

cart combination should be moved

1 Subwoofer

with car

e. Quick stops,

24

Safety Check – Upon completion of

1 Accessory pack containing:

excessive force and

any service or repairs to this product,

uneven surfaces may

ask the service technician to perform

4 Rubber feet

cause the product and

safety checks to determine that the

4 Spike feet

cart combination to

pr

oduct is in pr

oper operating

overturn. Check that there are no

condition.

4 Lock nuts

cables under the carpet that may be

25 Magnetic Fields – the product creates

1 International warranty document

damaged by the spike feet. Do not

a stray static magnetic field. Do not

walk the pr

oduct on the spike feet as

place any object that may be damaged

A tour of the subwoofer

this may cause them to become

by this magnetic field (eg cathode ray

(figure 2)

detached fr

om the cabinet and cause

tube televisions or computer monitors,

damage. Take care not to impale

1

Power/Standby indicator

audio and video tapes and swipe

yourself with the spike feet.

cards) within 0.5m (2 feet) of the

2 VOLUME control

19 Non-use Periods – The power cord of

appliance. The appliance may cause

3 LOW-PASS FREQUENCY control

the appliance should be unplugged

distortion of cathode ray tube images

fr

om the outlet during lightning storms

beyond this distance.

4 MODE On/Auto/Standby switch

or when the apparatus is left unused

5

Equalisation switch

for a long period of time.

Introduction

6

LOW-P

ASS FILTER defeat switch

20 Servicing – Do not attempt to service

Thank you for pur

chasing a B&W ASW

this pr

oduct yourself, as opening or

Active Subwoofer.

7 Phase switch

removing covers may expose you to

Since its foundation in 1966, the continuing

8

LINE IN

dangerous voltage or other hazards.

philosophy of B&W has been the quest for

Refer all servicing to qualified service

9

LINE OUT

perfect sound r

epr

oduction. Inspir

ed by the

personnel.

company’s founder, the late John Bowers,

10 LINK OUT

21 Damage Requiring Service – Unplug

this quest has entailed not only high

11

POWER on/of

f switch

this product from the wall outlet and

investment in audio technology and

refer servicing to qualified personnel

innovation but also an abiding appreciation

12

Fuse holders

under the following conditions:

of music and the demands of film sound to

13 Power input socket

3

ASW 825-855 inside 8/6/05 4:35 pm Page 4

Positioning the subwoofer

Electrical connections

to discover something has been wrongly

connected. Make sur

e that:

Because the subwoofer pr

oduces only low-

Disconnect all sound system equipment

frequency sounds, positioning is less critical

from the power supply until the signal

•

The phasing is correct – there should

in some respects compared to full-range

connections have been made and checked.

be no positive to negative connections

speakers. Dir

ectional information is much

This avoids the risk of damage whilst

to the satellite speakers. If something

less precise and you have more choice

connections are made or broken.

is out of phase you may get a fuzzy

where to place the speakers to good effect.

sound with an impr

ecise and floating

The function of the subwoofer is to receive

This said, best r

esults are obtained if the

image, a lack of bass or a combination

signals from the amplification chain and,

subwoofer is placed between the satellite

of the two.

wher

e necessary for 2-channel audio, split

speakers or in the vicinity of one of them. If

the signal into low bass and higher

•

There are no left to right mix-ups – this

you use two subwoofers, it is best to put

frequencies and feed the latter back out to

can r

esult, for example, in the

one near each satellite speaker.

the satellite speakers. Left and right

orchestra being the wrong way round

Placing the subwoofer behind the listeners,

channel inputs may be combined into a

or

, more disastrously, sounds on your

even in surround sound installations,

single mono low bass feed to the

Home Theatr

e going in the opposite

generally gives inferior imaging, but may be

subwoofer drive unit if r

equired.

direction to the action on the screen.

an acceptable compromise if domestic

The subwoofer will input and output line-

considerations dictate.

Switching on and off

level signals via the RCA Phono sockets

As with all speakers, the proximity of room

located on the back panel.

We recommend that you switch the

boundaries af

fects the sound. Bass is

subwoofer on befor

e any power amplifiers

Use the following table to select the correct

generally incr

eased as more surfaces come

r

eceiving signals from the subwoofer.

wiring method for your installation:

into close proximity with the speakers.

Similarly, when switching off, switch the

Unlike full-range speakers, however

, you

subwoofer of

f last.

Application: Home Theatre

can always r

estore the correct overall

The MODE standby/auto/on switch (4) does

system balance by adjusting the volume

The subwoofer may be used with any

not isolate the amplifier completely fr

om the

level of the subwoofer

. The more boost you

decoder that has a line-level subwoofer

power supply. It maintains a low-power

get from the room, the less hard the

output (normally from an RCA Phono

input to an auxiliary sensing circuit.

speaker has to work; but there is a down

socket). Most decoders with integral power

side. Cor

ner positions often excite mor

e

amplifiers still output the subwoofer or

The switch (4) operates as follows:

low-fr

equency room resonances, making

Low-Frequency Effects (LFE) signal at line

On:

the bass more uneven with frequency.

level.

W

ith the switch in this position, the

Ther

e is no substitute for experiment as all

• Decoder with one or more subwoofers

amplifier remains permanently on, and the

r

ooms behave differently, so try the

– fig. 3

light (1) glows green.

subwoofer in a variety of positions before

making a final decision. A piece of music

Auto:

Application: 2-channel audio

with a bass line ascending or descending

On first switching the subwoofer to Auto,

the musical scale is useful for assessing the

Separate pre- & power amplifiers:

the amplifier becomes fully active and the

smoothness of the bass r

esponse. Listen

light (1) glows green. After a period of

a

One or mor

e subwoofers with output

for exaggerated or quiet notes. Having a

about 5 minutes without an input signal,

combined into a single mono signal –

separate subwoofer does enable you to

the amplifier automatically r

everts to

fig. 4

optimise for r

oom resonances

standby mode, and the light glows red.

independently from siting the satellite

b Two subwoofers with separate left and

When an input signal is detected, the

speakers for best imaging.

right signal – fig. 5

amplifier automatically becomes fully active

and the light glows green.

If the subwoofer is to be used in a confined

The subwoofer is not suitable for use with

space (eg in custom fur

niture), the space

2-channel integrated pr

e/power amplifiers.

Standby:

must be ventilated to allow suf

ficient air to

In this position, the amplifier is in

circulate and cool the unit. Ask your dealer

Using more than one subwoofer

permanent standby, and the light glows

for advice.

red.

Using more than one unit in a single

The subwoofer is supplied with four spike

installation can impr

ove performance in the

If the subwoofer is to be out of use for an

feet. The spikes pierce through carpet pile,

following ways:

extended period of time, we r

ecommend

giving a firm support directly to the floor

you isolate it from the power supply, either

• Maintain stereo separation to the

surface without crushing the pile.

by using the POWER switch (11) or by

lowest frequencies.

removing the plug from the power socket.

If the unit is to be placed on a vulnerable

•

Cope with larger listening rooms.

surface, such as a wooden floor

, either

Setting the controls

place a protective disc under each spike or

•

Enable gr

eater maximum sound output

fit the four rubber feet in place of the

– often useful for ef

fectively

There are 5 controls to consider:

spikes.

r

epr

oducing special effects in Home

• The VOLUME control (2)

Theatr

e applications.

When fitting either the rubber feet or the

•

The LOW-PASS FREQUENCY

spike feet, first screw the lock nuts fully

• Smooth out the effects of low-

control (3)

onto the thr

ead and then screw the feet

fr

equency r

oom r

esonances.

fully onto the thr

eaded inserts in the base

• The PHASE switch (7)

If you are using two subwoofers for

of the cabinet. If the unit r

ocks, loosen the

2-channel audio, separation is improved if

• The LOW-PASS FILTER switch (6)

relevant two opposing feet until the support

each channel has its own subwoofer,

is firm, then re-tighten the lock nuts to the

•

The EQ (equalisation) switch (5)

providing each one is placed close to the

inserts.

r

elevant satellite speaker

. Only use the

The optimum settings depend on the other

Check that ther

e ar

e no cables under the

mono connection of figure 4 if you cannot

equipment used with the subwoofer. If

carpet that may be damaged by the spike

place each subwoofer close to its satellite

using more than one subwoofer, ensure the

feet.

speaker.

contr

ols on each one ar

e set the same.

Do not walk the product on the spike feet

Double-check the connections

Use with home theatr

e decoders

as this may cause them to become

detached from the cabinet and cause

Befor

e auditioning the sound quality of your

The B&W ASW Active Subwoofer is not a

damage.

new installation and fine-tuning it, double-

THX® licensed component, but may be

check the connections. All too often, users

used with a THX® controller if desired.

Take care not to impale yourself with the

complain that they cannot get a decent

spike feet when moving the pr

oduct.

• Set the decoder VOLUME control to

sound however they set the controls, only

4

ASW 825-855 inside 8/6/05 4:35 pm Page 5

the half way (12 o’clock) position.

preserve separate right and left channel

distances from the subwoofer(s) and

information and ar

e sited close to the

satellite speakers to the listeners

• The setting of the LOW-PASS

r

elevant satellite speakers, using a higher

appr

eciably, reassess the phase switch

FREQUENCY contr

ol is irrelevant.

cut-off frequency may compromise the

setting. You should also check the level

•

Set the PHASE switch initially to 0˚.

ster

eo image and should only be

setting of the subwoofer (using either the

consider

ed if the bass performance of the

decoder output levels or the volume contr

ol

•

Set the LOW-PASS FILTER switch

satellite speakers is particularly limited.

on the subwoofer amplifier as appropriate),

to

OUT.

but only after setting the phase corr

ectly.

At each setting of the cut-off frequency,

•

Set the EQ switch initially to position A.

listen with the phase switch in both

Taking care of the subwoofer

See also the section “Fine tuning”.

positions. The corr

ect one is that which

gives the fullest bass and that will depend

The cabinet of the subwoofer may be

If you have a THX® contr

oller, ensure that

on the bass characteristics of your satellite

cleaned by dusting with a dry cloth. If you

the subwoofer function is enabled. When

speakers and the r

elative distances of the

wish to use an aerosol cleaning spray, do

so configur

ed it incorporates all the filtering

subwoofer(s) and the satellite speakers to

not spray directly on the cabinet; spray

and level setting r

equired for the subwoofer

the listeners. When using mor

e than one

onto the cloth. Remove the grille first so

in all modes. For level calibration, the

subwoofer

, ensure that each one has its

that the cloth does not become stained,

internal test noise and channel level

cut-off frequency and phase switch set the

but be car

eful not to disturb the drive unit.

contr

ols in the THX® controller should be

same way

.

The grille itself may be cleaned using a soft

used. In all cases the levels should be set

brush.

to obtain 75dB SPL (C-weighted) at the

Set the loudness of the subwoofer relative

listening position from the controller’s

to the satellite systems to your liking. Use a

Do not use the subwoofer as a table. When

internal noise test signal.

wide variety of programme material to get

in use, objects left on top of the subwoofer

an average setting. One that sounds

ar

e liable to rattle. In particular, avoid the

With other decoders, configure the front

impressive on one piece may sound

risk of liquids being spilled (eg from drinks

and surround speakers to “large” or “small”

overpowering on another. Listen at realistic

or vases of flowers).

as appropriate before setting the levels.

levels as the per

ception of balance varies

Use the internal noise test signal and

If the system is taken out of use for a long

with sound level.

volume contr

ols of the decoder to set the

period, disconnect the subwoofer fr

om the

levels of all the speakers. Only change the

power supply.

Home theatre

VOLUME control on the subwoofer if there

Note: The subwoofer will automatically

is not enough range in the decoder to

The situation with home theatr

e is

shut down if driven excessively. If this

achieve the corr

ect levels.

somewhat dif

fer

ent fr

om 2-channel audio.

occurs, r

e-set the subwoofer by turning it

The subwoofer (LFE) signal is a separate

Inexpensive sound level meters are readily

off then on again, using the power on/off

channel rather than an extension of the

available from electronics stores and should

switch on the amplifier panel.

signal to the satellite speakers. The LOW-

be used to calibrate the levels. Refer to

PASS filter is switched out, because the

your decoder manual for further details on

decoder provides all the filtering for any

how to set the levels.

speakers set to “small”. However, the

position of the phase switch must still be

Use for 2-channel audio

assessed. Normally the phase will be set to

•

Set the VOLUME contr

ol initially to the

0˚, but if the subwoofer is positioned at a

half way (12 o’clock) position.

distance significantly different from the

other speakers, or the power amplifier

• Set the LOW-PASS FREQUENCY

driving the other speakers happens to

initially to 80Hz.

invert the signal, the 180˚ position may be

• Set the LOW-PASS FILTER switch

preferable. Listen with the switch in both

to IN.

positions and choose the one that gives the

fullest sound. If there is little difference,

• Set the EQ switch initially to position A.

leave the switch at 0˚.

•

Set the PHASE switch initially to 0˚.

Decoders normally have a calibrated noise

See also the section “Fine tuning”.

signal that can be used to set the r

elative

levels of all the speakers, making the task

Fine-tuning

somewhat more straightforward than for

2-channel audio. However

, do not be afraid

There are two settings of the EQ switch.

to alter the settings to your personal

Position B is optimised to allow the

preference. It is all too easy to get carried

subwoofer to provide the highest listening

away with the capabilities of the subwoofer,

levels, while position A gives greater bass

especially with some special low-fr

equency

extension coupled with a tighter sound.

effects. Often a more realistic portrayal, and

one mor

e satisfying in the long term, is to

2-channel audio

be had by setting the subwoofer level lower

The optimum settings of the PHASE switch

that the standard calibration level.

and the LOW-P

ASS FREQUENCY control

ar

e inter

-related and also dependent on the

All applications

low-fr

equency cut-of

f characteristic of the

If you get problems with lumpy bass – if

satellite speakers and the relative positions

certain bass notes ar

e exaggerated mor

e

of all the speakers in the installation.

than others – then you probably have a

Set the system up in the pr

eferr

ed position

room interface problem and it is worth

and play some programme with a steady

experimenting with the placement of the

bass content. The optimum setting for the

subwoofer

. What may seem like small

LOW-PASS FREQUENCY depends on

changes in position – 15cm (6in) or so –

several variables; the bass performance

can have a pr

ofound effect on the sound.

and power handling of the satellite

Try raising the subwoofer clear of the floor

speakers, the number of subwoofers used

as well as lateral movement. The use of

and their position relative to the satellite

multiple subwoofers can smooth the ef

fects

speakers. The range 80 – 90Hz is a good

of room resonances, as each subwoofer

starting point for the LOW-P

ASS fr

equency

.

will tend to excite resonances at different

Unless two subwoofers are used to

frequencies. If you alter the relative

5