Harman Kardon 75 Owners Manual - Page 6

SPEAKER

PHASING

For

maximum

enjoyment

of

multichannel

sound,

it

is

important

to

have

the

four

speaker

systems

in

phase.

The

phase

relationship

must

be

correct,

not

only

between

the

front

left

and

right

speaker

systems,

the

back

left

and

right

speaker

systems,

but

also

between

the

front

and

back

channels.

When

connecting

each

speaker

system

to

the

receiver,

be

certain

to

main-

tain

plus

and

minus

polarities.

If

your

speakers

do

not

have

a

plus/minus

polarity

identification,

phasing

can

be

accomplished

by

the

following

procedure:

1.

After

connecting

your

speakers,

place

the

receiver

in

the

MONO

mode

of

operation

and

the

SOUND

FIELD

BALANCE

control

to

the

exact

top

center

position.

2.

Play

a

record,

tape

or

FM

broadcast

which

has

a

single

speaking

or

singing

voice,

or

a

solo

instrument.

3.

The

voice

or

instrument

should

appear

to

be

emerging

from

an

area

some-

where

in

the

center

of

the

two

speakers.

If

the

voice

seems

to

come

from

both

speakers

independently,

the

speakers

are

out

of

phase.

4.

If

you

determine

that

your

speakers

are

out

of

phase,

merely

disconnect

the

leads

from

only

one

of

the

speakers

and

reverse

them.

Your

stereo

system

will

now

be

in

phase.

This

completes

the

phasing

of

a

pair

of

speakers

for

stereo

operation.

It

should

be

noted

that

it

is

not

necessary

to

match

the

impedance

of

the

speakers

to

the

receiver

since

the

75

+

is

a

solid

state

instrument

and

can

accommodate

all

speakers

ranging

in

impedance

from

4

to

16

ohms

without

special

trans-

formers.

Repeat

this

process

for

all

additional

pairs

of

speakers

in

your

system.

OPERATING

PROCEDURE

Every

control

on

this

receiver

serves

a

specific

and

useful

function

and

is

important

for

the

proper

operation

of

your

stereo

or

4

-Channel

system.

Read

this

section

carefully

so

you

can

take

full

advantage

of

all

the

per-

formance

capabilities

of

this

receiver.

SWITCHES

AND

CONTROLS

-

REAR

PANEL

STEREO/4-CH

SWITCH

The

75

+

receiver

is

shipped

with

the

STEREO/4-CH

switch

in

the

4

-CH

mode.

A

special

safety

latch

is

fitted

next

to

the

switch

to

prevent

throwing

the

switch

accidentally

while

the

receiver

is

turned

on.

If

you

plan

to

use

the

75

+

as

a

DOUBLE

-POWER

STEREO

receiver,

first

turn

off

the

unit,

remove

the

safety

latch

and

throw

the

STEREO/4-CH

switch

to

STEREO.

NOTE:

After

changing

position

of

this

switch

ALWAYS

replace

the

safety

latch.

The

two

front

channels

now

have

the

capability

of

delivering

double

power

to

your

speakers.

NOTE:

WHEN

THE

STEREO/4-CH

SWITCH

IS

IN

THE

STEREO

POSITION

THE

BACK

SPEAKERS

ARE

INOPERATIVE.

IF

YOU

WISH

TO

USE

THE

RECEIVER

TO

POWER

ANY

BACK

SPEAKERS,

FIRST

TURN

OFF

THE

RECEIVER.

REMOVE

THE

LATCH

AND

THROW

THE

STEREO/4-CH

SWITCH

TO

4

-CH.

REPLACE

THE

PROTECTIVE

LATCH.

STEREO

THRESHOLD

CONTROL

This

rear

panel

control

can

be

adjusted

to

determine

the

number

of

stereo

stations

the

tuner

will

reproduce

in

the

STEREO

FM

position

of

the

Function

Switch.

In

the

full

counterclockwise

position,

the

automatic

switching

circuits

have

maximum

sensitivity

and

all

stereo

stations

within

the

range

of

the

tuner

will

be

reproduced.

However,

due

to

weak

signals

(or

their

distance

from

your

an-

tenna)

some

stations

will

contain

noise

levels

which

degrade

performance

when

reproduced

in

stereo.

In

order

to

reproduce

these

stations

monophonically

(when

in

the

STEREO

FM

position

of

the

Function

Switch),

rotate

the

STEREO

THRESHOLD

control

clockwise

until

only

good

quality

stereo

stations

are

reproduced.

MUTING

THRESHOLD

CONTROL

This

rear

panel

control

adjusts

the

level

at

which

muting

action

will

take

place.

Minimum

muting

action

occurs

in

the

full

counterclockwise

position.

Maximum

muting

is

achieved

in

the

full

clockwise

position.

The

full

clockwise

position

will

also

eliminate

stations

with

poor

trans-

mission

quality.

The

control

should

be

adjusted

to

the

point

where

you

receive

only

those

stations

which

meet

your

standards

of

broadcast

quality.

SWITCHES

AND

CONTROLS

-

FRONT

PANEL

POWER

SWITCH

The

POWER

switch

performs

the

function

as

its

name

denotes.

It

supplies

power

to

the

receiver.

When

the

pushbutton

is

depressed

to

turn

the

set

ON

the

power

light

will

illuminate.

5

Harman Kardon 75 Owners Manual - Page 6

Operating, Procedure

Page 6 highlights