Bose 901 Series IV Owner's guide - Page 15

B.

ADJUSTING

THE

LOW

AND

HIGH

FREQUENCY

SOURCE

AND

ROOM

COMPENSATION

CONTROLS

1.

Select

a

well

-recorded

familiar

record

with

a

full

orchestral

passage

or

a

record

with

a

large

number

of

diverse

musical

instruments

that

span

the

entire

frequency

range.

Select

a

recorded

passage

that

has

sustained

music

over

several

seconds

so

you

can

observe

the

effects

of

the

controls.

2.

Preset

the

HIGH

FREQUENCY

Control

in

the

center.

3.

Move

the

LOW

FREQUENCY

Control

back

and

forth

several

times

over

the

extremes

of

the

control's

range

and

carefully

listen

to

its

effect.

You

will

notice

a

dramatic

change

in

the

basic

fullness

or

body

of

the

sound

without

changing

the

deep

bass

or

midrange.

Starting

with

the

con-

trol

at

the

extreme

left,

slowly

move

the

knob

until

the

balance

of

the

sound

is

rich

and

full,

but

without

excessive

heaviness.

4.

Next,

replay

the

same

passage

again

and

move

the

HIGH

FREQUENCY

Control

over

the

extremes

of

the

range

several

times,

listening

to

its

effect.

Starting

with

the

con-

trol

set

at

the

extreme

left,

slowly

move

the

knob

until

the

sound

fills

with

instrumental

detail

clarity,

and

presence.

Note

that

since

no

room

is

typical,

it

will

be

rare

that

the

center

setting

of

both

controls

is

used.

Accordingly,

it

is

important

to

realize

that

it

is

your

adjustment

of

these

controls

that

will

result

in

the

speakers

optimum

perfor-

mance.

LOW

FILTER

CONTROL

The

901

Active

Equalizer

features

a

newly

-designed

LOW

FILTER

Control.

The

LOW

FILTER

Switch

can

be

used

to

reduce

the

lowest

two

octaves

of

bass

energy

without

affec-

ting

the

mid

-bass

response.

This

control

is

most

useful

in

removing

record

or

turntable

rumble.

OW

%ITER

"Ii

:011

ISL0UT

1

315

1.00O

1001

FREQUENCY

IN

CYCLES

PER

SECOND

901

IV

EQUALIZER

CONTROL

RESPONSE

10.000

20110

C.

SPEAKER

PLACEMENT

Several

options

are

possible

regarding

placement

of

your

901

in

your

listening

room.

Shelving

that

is

deep

enough

to

provid.

the

necessary

distances

behind

and

to

the

side

of

the

speake

system

can

be

used.

Make

certain

the

shelving

is

substantie

and

not

the

same

shelf

used

to hold

your

turntable,

as

possibl.

acoustic

feedback

can

occur.

Many

people

choose

the

attractive

pedestals

available

wit

the

901

Series

IV

System.

If

you

choose

this

method

of

suppor

instructions

are

provided

with

the

pedestals

for

connectin

and

mounting

the

speaker

system,

using

the

four

predrille

holes

(A)

in

the

speaker

bottom.

Another

placement

idea

is

to

suspend

the

speaker

syster

from

the

ceiling

(see

Figure

1).

This

placement

method

i

particularly

attractive

if

wall

surfaces

are

interrupted

by

wir

dows

or

doorways

or

if

floor

placement

is

difficult

due

t

furniture

or

the

presence

of

children.

15

Bose 901 Series IV Owner's guide - Page 15

instructions

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