Harman Kardon AX20 Owners Manual - Page 10

monaural

low

level

magnetic

cartridge

or

high

level

ceramic

cartridge.

The

TUNER

position

selects

your

monaural

tuner

for

operation

and

the

AUX

po-

sition

selects

your

monaural

tape

recorder

or

other

auxiliary

monaural

equip-

ment.

Speaker

Selector

Switch:

In

a

monaural

installation

where

more

than

one

set

of

speakers

are

installed

(for

example:

one

speaker

in

the

living

room

and

another

in

the

den)

selection

between

the

two

speakers

is

made

by

operating

the

SPEAKER

SELECTOR

switch

on

the

front

panel.

To

operate

Speaker

A

(located

in

your

living

room)

set

the

LEFT

SPEAK-

ER

SELECTOR

switch

located

on

the

front

panel

.

to

"A".

To

select

Speaker

B

(located

in

another

room)

set

the

SPEAKER

SELECTOR

switch

to

"B".

To

operate

both

speakers

simultaneously

set

the

SPEAKER

SELECTOR

switch

to

"AB".

Rumble

Filter:

At

times,

record

changers,

records

and

even

some

turntables,

produce

an

objectionable

low

frequency

signal

that

is

strong

enough

to

be

introduced

into

the

sensitive

playback

system.

Known

as

"Rumble",

this

undesirable

signal

can

he

eliminated

by

the

special

RUMBLE

FILTER

switch

incorporated

in

the

Model

AX20.

Whenever

rumble

is

encountered,

set

the

switch

to

"ON".

Equalization

Switch:

Records

and

tapes

are

recorded

with

special

emphasis

and

deemphasis

of

certain

frequencies

in

order

to

achieve

maximum

dynamic

range.

To

play

back

your

records

and

tapes

faithfully,

it

is

necessary

to

"equalize"

their

frequency

response.

When

playing

your

monaural

records

set

the

EQUALIZATION

switch

to

the

RIAA

or

EUR

position

depending

on

the

recommendation

of

the

record

com-

pany.

If

you

are

in

doubt

as

to

the

proper

equalization

setting,

set

the

switch

for

best

listening

quality.

When

you

are

using

your

monaural

tape

deck

through

the

TAPE

HD

jack,

set

the

equalization

switch

to

either

3%

or

7;‘

depending

on

the

tape

speed

used.

Proper

playback

equalization

is

then

automatically

selected.

ADJUSTMENTS

Output

Balance:

This

control

is

located

between

the

output

transformer

and

the

EL84

output

tubes.

It

balances

the

two

EL84's

for

lowest

power

hum

and

distortion.

Adjust-

ment

is

quite

simple:

allow

the

amplifier

to

remain

in

operation

for

at

least

15

minutes.

Turn

the

Loudness

control

to

minimum.

Now

while

listening

to

the

speaker

connected

to

the

AX20,

adjust

this

control

for

minimum

hum.

Due

to

the

extremely

low

hum

level

of

the

AX20,

this

is

best

done

at

a

time

when

the

room

is

very

quiet.

The

setting

for

minimum

hum

is

attained

only

when

the

two

power

tubes

have

been

exactly

balanced,

and

this

is

the

condition

for

absolute

minimum

distortion.

Harman Kardon AX20 Owners Manual - Page 10

Speaker, Selector, Switch, Rumble, Filter, Equalization, ADJUSTMENTS, Output, Balance

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