Harman Kardon A250 Owners Manual - Page 8

Lead

Dress:

A

black

plastic

clamp

is

located

on

the

rear

of

the

chassis

near

the

input

receptacles.

Remove

the

rubber

clamp

on

the

upper

portion

of

the

block,

insert

the

shielded

leads

into

the

clamp

assembly

and

replace

the

rubber

clamp.

This

will

offer

a

neat

installation.

OPERATING

THE

MODEL

A-250

AS

A

MONAURAL

AMPLIFIER

The

Model

A-250

incorporates

the

folloWing

front

panel

controls.

Viewing

the

instrument

from

left

to

right

you

will

note

a

TREBLE

control

(on/off

switch

is

incorporated

in

this

control),

BASS

control,

LOUDNESS

control,

BALANCE

control,

MODE

switch

and

FUNCTION

switch.

On

the

upper

left

section

of

the

front

panel

you

will

note

two

SPEAKER

SELECTOR

switches

and

a

CON-

TOUR

switch.

On

the

upper

right

there

is

a

RUMBLE

FILTER

switch,

a

SCRATCH

FILTER

switch

and

an

EQUALIZATION

switch.

TECHNICAL

EXPLANATION

OF

THE

CONTROLS

-

Bass

and

Treble:

These

controls

provide

the

full

range

of

tonal

adjustment

necessary

for

high

fi

delity

listening.

These

controls

can

either

boost

or

cut

the

bass

and

treble

tones

of

your

monaural

system.

The

controls

should

be

set

in

accordance

with

your

listening

preference,

speaker

characteristics

and

room

acoustics.

Loudness

Control:

This

control

adjusts

the

volume

level

of

any

program

material

fed

into

your

high

fi

delity

system.

Its

effect

can

be

modified

by

the

CONTOUR

switch.

Contour

Switch:

One

of

the

limitations

of

human

hearing

is

its

tendency

to

lose

sensitivity

to

the

very

low

pitched

sounds,

as

the

program

sound

level

is

reduced.

It

is

this

characteristic

(known

as

the

Fletcher

-Munson

effect)

which

causes

one

to

play

music

programs

at

high

listening

level

in

order

to

experience

the

full

rich

tone

available

from

fi

ne

modern

recordings.

The

Harman-Kardon

CONTOUR

switch

compensates

for

the

Fletcher

-Munson

effect,

thus

eliminating

high

listening

levels

as

a

requisite

for

full

enjoyment

of

reproduced

music.

For

low

level

listening

throw

the

CONTOUR

switch

located

on

the

front

panel

to

either

number

1

or

number

2

position,

depending

on

your

listening

preference.

You

will

note

how

the

low

frequencies

become

more

apparent

while

the

volume

level

remains

unchanged.

Balance

Control:

This

control

has

no

function

in

monaural

listening

and

should

be

left

in

the

center

position.

If

rotated

to

either

extreme

position,

it

would

completely

shut

off

the

preamplifier

on

that

side.

Mode

Switch:

The

only

application

for

this

switch

in

monaural

operation

is

to

select

be-

tween

the

two

preamplifiers.

This

allows

for

double

the

usual

number

of

input

jacks

found

on

ordinary

monaural

amplifiers.

The

STEREO

NORMAL

and

MONAURAL

RIGHT

positions

are

identically

connected

and

will

activate

the

Right

preamplifier,

therefore

switching

on

all

program

material

connected

to

this

preamplifier.

STEREO

REVERSE

and

MONAURAL

LEFT

are

identically

con-

nected

and

will

activate

the

Left

preamplifier.

For

simplicity,

it

is

suggested

to

use

only

the

MONAURAL

RIGHT

and

MONAURAL

LEFT

positions

on

the

MODE

switch

for

monaural

operation.

Switch

to

MONAURAL

RIGHT

or

MONAURAL

LEFT

as

a

function

of

the

preamplifier

you

wish

to

use.

Function

Switch:

The

FUNCTION

switch

selects

the

desired

type

of

program

source

and

has

fi

ve

positions:

AUX

1

and

AUX

2

selects

equipment

connected

to

the

Harman Kardon A250 Owners Manual - Page 8

operation.

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