Adcom Gfa-5802 User manual

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2

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A

DCOM

details

you

can

hear

G

FA-5802

High

Current

MOSFET

Power

Amplifier

OWNER’S

MANUAL

THE

FOLLOWING

PRECAUTIONS

AND

SAFETY

INSTRUCTIONS

ARE

REQUIREMENTS

OF

UL

AND

CSA

SAFETY

REGULATIONS

Warning:

To

reduce

the

risk

of

fire

or

electric

shock,

do

not

expose

this

unit

to

rain

or

moisture.

A

CAUTION

RISK

OF

ELECTRIC

SHOCK

DO

NOT

OPEN

AVIS;

RISQUE

DE

CHOC

ELECTRIQUE-NE

PAS

OUVRiR

The

graphic

symbol

of

a

lightning

flash

with

an

arrow

point

within

a

triangle

signifies

that

there

is

dangerous

voltage

within

the

unit

and

it

poses

a

hazard

to

anyone

removing

the

cover

to

gain

access

to

the

interior

of

the

unit

Only

qualified

service

personnel

should

make

any

such

attempt.

The

graphic

symbol

of

an

exclamation

point

within

an

equilateral

triangle

warns

a

user

of

the

device

that

it

is

necessary

to

refer

to

the

instruction

manual

and

its

warnings

for

proper

operation

of

the

unit

Do

not

place

this

unit

on

an

unstable

cart,

stand,

tripod,

bracket,

or

table

The

unit

may

fall,

causing

serious

injury

to

a

child

or

adult,

and

serious

damage

to

the

unit

Use

only

with

a

cart,

stand,

tripod,

bracket,

or

table

recommended

by

the

manufacturer,

or

sold

with

the

unit

Any

mounting

of

the

device

should

follow

the

man¬

ufacturer’s

instructions,

and

should

use

a

mounting

ac¬

cessory

recommended

by

the

manufacturer

Read

all

the

safety

and

operating

instructions

before

connecting

or

using

this

unit

Retain

this

notice

and

the

owner’s

manual

for

future

reference

All

warnings

on

the

unit

and

in

its

operating

instructions

should

be

adhered

to

All

operating

and

use

instructions

should

be

followed

Do

not

use

this

unit

near

water;

for

example,

near

a

bathtub,

washbowl,

kitchen

sink,

laundry

tub,

in

a

wet

basement,

or

near

a

swimming

pool

The

unit

should

be

installed

so

that

its

location

or

position

does

not

interfere

with

its

proper

ventilation

For

example,

it

should

not

be

situated

on

a

bed,

sofa,

rug,

or

similar

surface

that

may

block

the

ventilation

openings,

or

placed

in

a

built-in

installation,

such

as

bookcase

or

cabinet,

that

may

impede

the

flow

of

air

through

its

ventilation

openings

The

unit

should

be

situated

away

from

heat

sources

such

as

radiators,

heat

registers,

stoves,

or

other

devices

(including

amplifiers)

that

produce

heat

The

unit

should

be

connected

to

a

power-supply

outlet

only

of

the

voltage

and

frequency

marked

on

its

rear

panel

The

power-supply

cord

should

be

routed

so

that

it

is

not

likely

to

be

walked

on

or

pinched,

especially

near

the

plug,

convenience

receptacles,

or

where

the

cord

exits

from

the

unit.

Clean

unit

only

as

recommended

in

its

instruction

manual

The

power-supply

cord

of

the

unit

should

be

unplugged

from

the

wall

outlet

when

it

is

to

be

unused

for

a

long

period

of

time

Care

should

be

taken

so

that

objects

do

not

fall,

and

liquids

are

not

spilled,

into

the

enclosure

through

any

openings

This

unit

should

be

serviced

by

qualified

service

personnel

when

A.

The

power

cord

or

the

plug

has

been

damaged,

or

B

Objects

have

fallen,

or

liquid

has

been

spilled,

into

the

unit;

or

C

The

unit

has

been

exposed

to

rain,

or

liquids

of

any

kind,

or

D

The

unit

does

not

appear

to

operate

normally,

or

exhibits

a

marked

change

in

performance;

or

E

The

device

has

been

dropped,

or

the

enclosure

damaged

DO

NOT

ATTEMPT

SERVICING

OF

THIS

UNIT

YOURSELF.

REFER

SERVICING

TO

QUALIFIED

SERVICE

PERSONNEL.

ATTENTION

POUR

PREVENIR

LES

CHOCS

ELECTRIQUES

NE

PAS

UTILISER

CETTE

FICHE

POLARISEE

AVEC

UN

PROLONGATEUR,

UNE

PRISE

DE

COURANT

OU

UNE

AUTRE

SORTIE

DE

COURANT,

SAUF

SI

LES

LAMES

PEUVENT

£TRE

INSEREES

A

FOND

SANS

EN

LAISSER

AU-

CUNE

PARTIE

A

DECOUVERT

CAUTION

TO

PREVENT

ELECTRIC

SHOCK

DO

NOT

USE

THIS

POLARIZED

PLUG

WITH

AN

EXTENSION

CORD,

RECEPTACLE

OR

OTHER

OUTLET

UN¬

LESS

THE

BLADES

CAN

BE

FULLY

INSERTED

TO

PREVENT

BLADE

EXPOSURE

CAUTION

POWER

LINES

Any

outdoor

antenna

must

be

located

away

from

all

power

lines.

OUTDOOR

ANTENNA

GROUNDING

if

an

outside

antenna

is

connected

to

your

tuner

or

tuner-preamplifier,

be

sure

the

antenna

system

is

grounded

so

as

to

provide

some

protection

against

voltage

surges

and

built-up

static

charges.

Section

810

of

the

National

Electrical

Code,

ANSI/NFPA

No.

70-1984,

provides

information

with

respect

to

proper

grounding

of

the

mast

and

supporting

structure,

grounding

of

the

lead-in

wire

to

an

antenna

discharge

unit,

size

of

grounding

conductors,

location

of

antenna

discharge

unit,

connection

to

grounding

electrodes,

and

requirements

for

the

grounding

electrode.

a.

use

No.

10

AWG

(5.3

mm

2

)

copper,

No.8

AWG

(8.4

mm

2

)

aluminum,

No.17

AWG

(1.0

mm

2

)

copper-clad

steel

or

bronze

wire,

or

larger,

as

a

ground

wire.

b.

Secure

antenna

lead-in

and

ground

wires

to

house

with

stand-off

insulators

spaced

from

4-6

feet

(1.22-1.83

m)

apart.

c.

Mount

antenna

discharge

unit

as

close

as

possible

to

where

lead-in

enters

house.

d.

Use

jumper

wire

not

smaller

than

No.6

AWG

(13.3

mm

2

)

copper,

or

the

equivalent,

when

a

separate

antenna-grounding

electrode

is

used.

See

NEC

Section

810-21

(j).

EXAMPLE

OF

ANTENNA

GROUNDING

AS

PER

NATIONAL

ELECTRICAL

CODE

INSTRUCTIONS

CONTAINED

IN

ARTICLE

810

-

RADIO

AND

TELEVISION

EQUIPMENT

POWER

LINES

STANDOFF

INSULATORS,

b

POWER

SERVICE

GROUNDING

ELECTRODE

SYSTEM

(e

g.

intenor

metal

water

pipe)

ANTENNA

LEAD-IN

WIRE

TO

EXTERNAL

ANTENNA

TERMINALS

OF

RADIO

RECEIVER

BONDING

JUMPER,

d

GROUND

WIRE,

a,b

GROUND

CLAMPS

OPTIONAL

ANTENNA

GROUNDING

ELECTRODE

DRIVEN

8

FEET

(2

44

M)

INTO

THE

EARTH

IF

REQUIRED

BY

LOCAL

COOES

SEE

NEC

SECTION

810-21

(f)

NOTE

TO

CATV

SYSTEM

INSTALLER

This

reminder

is

provided

to

call

the

CATV

system

installer’s

attention

to

Article

820-22

of

the

National

Electrical

Code

that

provides

guidelines

for

proper

grounding

and,

in

particular,

specifies

that

the

cable

ground

shall

be

connected

to

the

grounding

system

of

the

building,

as

close

to

the

point

of

cable

entry

as

practical.

INTRODUCTION

Congratulations

on

your

decision

to

purchase

the

GFA-5802

Stereo

Power

Amplifier.

You

have

made

a

wise

choice

that

will

reward

you

with

exceptionally

accurate

and

musical

sound

reproduction

for

years

to

come

To

realize

the

full

potential

of

your

new

amplifier,

please

read

these

operating

and

installation

instructions

thoroughly

before

attempting

to

connect

it.

FEATURES

•

Precision

matched

MOSFETs

used

throughout

the

signal

path.

•

Over

100,000

pF

of

power

supply

filter

capacitance

with

low

ESR

for

greater

reserve

capacity.

•

Reduced

number

of

gain

stages

improves

signal

reproduction

accuracy.

•

Custom

toroidal

power

transformer

with

dual

secondaries

provides

greater

peak

current

capability.

•

Separate

front-end

power

supply

complete

with

separate

transformers.

•

Dual

High

quality,

gold

plated

binding

posts.

•

Independent

thermal

protection

and

distortion

LED’s

for

each

channel.

•

Gold

plated

RCA

jacks.

•

Large

external

heatsinks

for

greater

cooling

capability

of

output

devices.

•

Heavy

gauge,

anodized

aluminum

front

panel

•

Powder

coated,

baked

chassis

and

top

cover

for

greater

durability.

•

Cooling

vents

on

top

cover

for

greater

efficiency

and

cooler

operation

while

driving

low

impedance

loads

IMPORTANT

NOTICE:

ADCOM

PROTECTION

PLAN

(USA

ONLY)

ADCOM

offers

the

enclosed

valuable

Limited

Warranty.

Please

read

the

details

on

the

Warranty

Card

carefully

to

understand

the

extent

of

the

protection

offered

by

the

Warranty,

its

reasonable

limitations,

and

what

you

should

do

in

order

to

obtain

its

benefits.

Be

sure

to

verify

that

the

serial

number

printed

on

the

rear

panel

matches

the

serial

number

on

the

outer

carton.

If

any

number

is

altered

or

missing,

you

should

notify

us

immediately

in

order

to

ensure

that

you

have

received

a

genuine

ADCOM

product

which

has

not

been

opened,

mishandled,

or

tampered

with

in

any

way.

UNPACKING

Before

your

new

GFA-5802

left

our

factory,

it

was

carefully

inspected

for

physical

imperfections

and

tested

for

all

electrical

parameters

as

a

routine

part

of

ADCOM’s

systematic

quality

control

This,

along

with

full

operational

and

mechanical

testing,

should

ensure

a

product

flawless

in

both

appearance

and

performance

After

you

have

unpacked

the

GFA-5802,

inspect

it

for

physical

damage

Save

the

shipping

carton

and

all

packing

material

as

they

are

intended

to

reduce

the

possibility

of

transportation

damage,

should

the

amplifier

ever

need

to

be

shipped

again.

In

the

unlikely

event

damage

has

occurred,

notify

your

dealer

immediately

and

request

the

name

of

the

carrier

so

a

written

claim

to

cover

shipping

damages

can

be

initiated.

THE

RIGHT

TO

A

CLAIM

AGAINST

A

PUBLIC

CARRIER

CAN

BE

FORFEITED

IF

THE

CARRIER

IS

NOT

NOTIFIED

PROMPTLY

IN

WRITING

AND

IF

THE

SHIPPING

CARTON

AND

PACKING

MATERIALS

ARE

NOT

AVAILABLE

FOR

INSPECTION

BY

THE

CARRIER.

SAVE

ALL

PACKING

MATERIALS

UNTIL

THE

CLAIM

HAS

BEEN

SETTLED.

PLACEMENT

AND

CARE

OF

THE

GFA-5802

During

normal

home

operation

the

heatsinks

of

the

GFA-5802

will

become

very

warm.

However,

there

are

instances

during

high-level

playback

into

low

impedances

when

the

heatsinks

will

become

much

warmer

than

usual.

To

ensure

the

amplifier’s

long-term,

trouble-free

operation,

it

is

necessary

to

provide

adequate

ventilation

for

the

heatsinks.

Therefore,

the

GFA-5802

should

be

kept

away

from

external

sources

of

heat

such

as

radiators

and

hot-air

ducts.

The

GFA-5802

should

never

be

placed

with

other

heat-producing

components

in

a

cabinet

or

enclosure

lacking

free

air

flow

If

you

require

that

the

GFA-5802

be

mounted

in

an

enclosed

cabinet,

it

is

recommended

that

the

rear

panel

of

the

cabinet

be

provided

with

ventilation

openings

at

the

top

and

bottom

to

allow

air

to

circulate

freely

in

the

cabinet

The

top

and

bottom

panel

of

the

amplifier’s

chassis

have

been

provided

with

vents

to

allow

the

necessary

cooling

of

the

internal

components.

It

is

important

that

these

vents

are

not

obstructed

in

any

way.

We

recommend

that

you

do

not

stack

other

components

on

top

of

the

GFA-5802.

This

is

particularly

important

If

your

system

includes

low-impedance

loudspeakers

which

are

difficult

to

drive,

or

if

you

will

consistently

demand

high

volume

levels

from

the

amplifier

and

speaker

system.

Not

only

will

heat

generated

by

the

amplifier

affect

the

performance

of

equipment

stacked

on

top

of

the

GFA-5802,

but

the

free

flow

of

air

through

the

ventilating

slots

in

the

amplifier

may

be

partially

obstructed

If

you

observe

these

recommendations,

the

GFA-5802

will

perform

reliably

in

any

reasonable

environment.

You

should

also

pay

attention

to

such

normal

considerations

as

protection

from

excessive

dust

and

moisture.

Occasional

vacuuming

of

accumulated

dust

on

the

chassis,

heatsinks,

panels

and

around

the

ventilating

slots

should

be

all

that

is

required

The

optimal

performance

of

your

new

GFA-5802

will

ultimately

depend

on

the

care

with

which

you

make

the

connections

between

the

amplifier,

preamplifier

and

the

loudspeakers

All

input

and

output

signal

connections

should

be

made

only

with

high

quality,

low-loss,

low

capacitance

cables

following

the

recommendations

in

the

following

relevant

sections.

1

WARNING

Whenever

connections

to

or

from

the

GFA-5802

are

being

made,

be

certain

that

the

AC

on/off

switch

of

the

amplifier

is

in

the

off

position,

the

AC

cord

of

the

amplifier

is

disconnected

from

the

AC

wall

outlet

and

that

all

associated

components

are

turned

off.

RIGHT/LEFT

UNBALANCED

(RCA)

INPUTS

O

The

audio

inputs

to

the

GFA-5802

are

through

two

high

quality,

gold

plated

RGA

jacks

to

minimize

high

frequency

line

losses,

noise,

etc.

This

input

type

is

more

common

that

the

balanced

XLR

input

(©)

and

is

designed

to

work

with

an

unbalanced

preamplifier.

They

will

accept

standard

RCA

type

plugs,

one

for

each

channel,

LEFT

and

RIGHT.

The

RIGHT

input

is

generally

represented

by

the

color

red,

while

LEFT

is

usually

represented

by

either

white

or

black.

To

preserve

the

correct

stereophonic

effects,

please

be

certain

to

connect

the

left

output

of

the

preamplifier

or

tuner-

preamplifier

to

the

RCA

jack

on

the

GFA-5802

labeled

LEFT

INPUT

and

the

right

output

of

the

source

component

to

the

RIGHT

INPUT

jack

To

ensure

that

the

performance

designed

into

the

GFA-5802

is

realized,

you

should

use

the

highest

quality

cables

feasible.

Whatever

cable

you

finally

select,

it

should

have

low

capacitance

Generally

speaking,

a

cable

with

a

capacitance

of

less

than

100

pF

will

work

best.

BALANCED/UNBLANCED

SWITCHES

0

These

switches

should

“point”

towards

the

input

that

you

are

using.

If

the

unbalanced

RCA

inputs

are

being

used,

then

the

switches

should

be

in

the

unbalanced

position.

If

you

are

using

the

balanced

XLR

inputs,

then

the

switches

should

be

in

the

balanced

position.

It

is

not

suggested

to

connect

both

the

balanced

input

to

a

balanced

source

and

the

unbalanced

input

to

an

unbalanced

source

at

the

same

time.

RIGHT/LEFT

BALANCED

(XLR)

INPUTS

0

When

you

are

using

a

preamp

that

has

balanced

outputs

(via

XLR

jacks),

it

may

be

directly

connected

to

the

GFA-

5802

using

“balanced

XLR"

cables.

Pushing

the

release

tab

on

the

top

of

the

input

will

release

the

XLR

NORMAL

SPEAKER

OUTPUTS

O

The

GFA-5802

is

“polarity

correct”

and

does

not

invert

phase.

That

is,

any

positive

going

signal

at

its

input

will

appear

as

a

positive

going

signal

at

its

output.

The

GFA-5802’s

connection

to

the

loudspeakers

are

made

through

two

high

quality,

five-way,

gold

plated

binding

posts

located

on

the

rear

panel.

These

terminals

will

accommodate

either

bare

wire,

tinned

wire,

terminal

pins,

spade

lugs

or

banana

plugs,

either

single

or

dual.

These

output

terminals

are

color

coded

RED

and

BLACK

to

indicate

polarity.

To

ensure

correct

stereo

phasing,

you

must

connect

the

RED

output

terminal

(labeled

“+”)

to

the

loudspeaker

input

terminal

color

coded

RED

(or

labeled

POSITIVE,

POS,

8

OHMS

or

4

OHMS).

The

BLACK

binding

post

terminal

on

the

amplifier

(labeled

”-”)

2

should

be

connected

to

the

loudspeaker

input

terminal

color

coded

BLACK

(or

labeled

NEGATIVE,

NEG,

C,

COMMON,

G,

or

GROUND).

The

RIGHT

OUTPUT

should

be

connected

to

the

right

channel

loudspeaker,

as

you

face

the

pair

of

loudspeakers,

and

the

LEFT

OUTPUT

to

the

left

channel

loudspeaker.

Generally

speaking,

when

making

connections

to

the

loudspeakers

from

the

amplifier

it

is

very

important

to

use

the

correct

type

and

size

of

wire

in

order

to

avoid

unnecessary

loss

of

amplifier

power

in

the

cable,

reduction

of

amplifier

damping

factor

and

other

undesirable

conditions.

It

is

suggested

that

with

the

GFA-5802

you

should

use

at

least

14AWG

wire

and

preferably

12AWG.

Contact

your

local

Adcom

dealer

for

an

appropriate

selection

of

high

end

cables.

Virtually

any

stereo

pair

of

loudspeakers

can

be

connected

to,

and

driven

by

the

GFA-5802.

The

amplifier

can

drive

low

impedances

at

more

than

adequate

power

levels

with

no

difficulty.

It

should

be

noted

here

that

many

loudspeaker

systems

which

are

nominally

rated

at

4

ohms

drop

in

impedance,

in

some

parts

of

their

frequency

range,

sometimes

to

below

2

ohms.

You

should

not

experience

difficulties

even

with

these

very

low

impedance

loads

unless

you

demand

excessively

high

volume

levels

from

the

system.

The

following

diagrams

show

basic

system

wiring

for

two

speaker

options.

BASIC

UNBALANCED

WIRING

DIAGRAM

3

BI-WIRE

SPEAKER

OUTPUTS

O

The

GFA-5802

incorporates

an

additional

set

of

output

terminals

to

facilitate

bi-wired

speaker

systems.

In

a

bi-wired

system,

there

are

two

sets

of

speaker-wires

that

connect

to

each

speaker

(one

for

the

low

frequencies

and

one

for

the

high

frequencies).

To

be

able

to

bi-wire

your

speakers,

the

speakers

need

to

be

bi-wirable

(having

two

sets

of

input

terminals,

usually

with

a

metal

jumper

installed

between

each

pair).

The

following

diagram

conveys

a

basic

bi-wired

system.

BASIC

BI-WIRED

DIAGRAM

AC

LINE

SOCKET

O

The

GFA-5802’sdetachable

power

cord

is

supplied

with

a

“grounded”

AC

plug.

Make

certain

that

the

power

cable

securely

plugged

into

the

AC

Line

Socket

on

the

GFA-5802.

4

FRONT

PANEL

FEATURES

POWER

LED

This

LED

will

glow

whenever

the

AC

ON/OFF

switch

is

turned

on

and

the

GFA-5802

is

energized.

The

POWER

LED

indicates

that

there

is

AC

voltage

being

fed

to

the

amplifier,

but

it

does

not

signify

that

all

the

amplifier’s

circuits

are

in

operation.

If,

for

example,

the

THERMAL

PROTECTION

LED

glows,

the

amplifier

will

not

produce

sound

even

though

the

POWER

LED

may

still

glow.

Additionally,

the

internal

power

transformer

is

provided

with

a

thermostat

which

will

interrupt

power

to

the

transformer

if

its

temperature

exceeds

125-C.

This

high

temperature

will

seldom,

if

ever,

be

encountered

unless

the

amplifier

is

subjected

to

abnormal

conditions,

such

as

operation

into

loads

of

less

than

2

ohms

at

very

high

listening

levels

for

long

periods

of

time,

etc

Once

the

temperature

within

the

transformer

decreases

to

a

normal

level,

the

thermostat

will

reset

itself

automatically

and

normal

operation

will

resume

INSTANTANEOUS

DISTORTION

ALERT

LED’s

The

INSTANTANEOUS

DISTORTION

ALERT

circuit

is

a

unique

ADCOM

distortion

detection

system

which

reads

all

forms

of

non-linear

distortion

such

as

THD,

IM,

slew-induced,

“clipping",

etc.

The

INSTANTANEOUS

DISTORTION

ALERT

LED’s

will

light

when

distortion

reaches

1%

regardless

of

impedance,

voltage/current

phase

angle

or

the

reactance

of

the

loudspeakers

which

the

amplifier

is

driving.

Sometimes,

when

the

amplifier

is

in

use,

the

LED’s

may

occasionally

flicker

during

high

volume

listening,

particularly

if

you

are

driving

low

impedances

This

flickering

is

no

cause

for

concern

The

LED’s

are

simply

warning

you

that

the

amplifier

has

reached

its

maximum

power

output

into

the

particular

loudspeakers

you

are

using.

If,

however,

the

INSTANTANEOUS

DISTORTION

ALERT

LED’s

glow

brightly

or

are

illuminated

most

of

the

time

during

playback,

you

are

overdriving

the

amplifier

and

should

turn

down

your

volume

control

to

reduce

the

listening

level,

otherwise

it

may

cause

the

THERMAL

PROTECTION

to

be

activated

or,

in

extreme

cases,

damage

your

loudspeakers

THERMAL

PROTECTION

LED’s

The

GFA-5802

is

provided

with

a

thermal

protection

circuit

which

will

shut

down

the

amplifier

if

either

heatsink’s

temperature

reaches

85-C

The

THERMAL

PROTECTION

LED’s

will

light

whenever

the

thermal

protection

circuit

on

its

respective

channel

has

been

triggered

and

the

amplifier

is

inoperative

The

thermal

protection

circuitry

will

typically

be

triggered

by

very

high

power

demands

into

impedances

much

lower

than

the

amplifier

is

capable

of

driving

at

those

levels.

If

either

amplifier

channel’s

output

through

the

loudspeaker(s)

ceases

abruptly,

and

one

or

both

of

the

THERMAL

PROTECTION

LED’s

glow,

you

will

know

that

the

circuitry

is

protecting

the

amplification

devices.

Once

the

temperature

of

the

heatsink(s)

drops

to

a

safe

operating

level,

the

amplifier

will

automatically

resume

operation.

Activation

of

the

thermal

protection

circuitry

in

the

GFA-5802

is

an

indication

that

the

amplifier

has

been

overdriven

or

that

the

load

the

loudspeakers

are

presenting

to

the

amplifier

is

unreasonably

low.

If

you

wish

to

prevent

recurring

activation

of

the

thermal

protection

circuitry,

you

must

reduce

the

volume

level

demands

or

correct

the

load-impedance

condition

which

may

be

causing

activation

of

this

circuitry,

or

both

internal

protection

fuses

may

blow.

Another

reason

that

the

THERMAL

PROTECTION

LEDs

will

glow

is

if

the

Speaker

Outputs

(O

or

©)

are

shorted

(if

the

positive

and

negative

wires

were

to

touch

together).

If

this

occurs,

you

will

experience

severe

distortion

from

the

speakers

for

a

few

seconds.

The

amplifier

will

then

shut

down

and

the

PROTECTION

LEDs

will

glow.

SERVICING

ADCOM

has

a

Technical

Service

Department

to

answer

questions

pertinent

to

the

installation

and

operation

of

your

unit.

In

the

event

of

difficulty,

please

contact

us

for

prompt

advice.

If

your

problem

cannot

be

resolved

through

our

combined

efforts,

we

may

refer

you

to

an

authorized

repair

agency,

or

authorize

return

of

the

unit

to

our

factory

Please

address

mail

inquires

to.

ADCOM

Service

Corporation

11

Elkins

Road

East

Brunswick,

NJ

08816

USA

Phone

or

fax

inquires

to

1

Telephone:

(908)

390-1130

or

after

7/97

(732)

Fax:

(908)

390-9152

or

after

7/97

(732)

Monday

through

Friday

9:00

AM

to

5:00

PM

EST

When

calling

or

writing

about

your

GFA-5802,

be

sure

to

note

and

refer

to

its

serial

number

as

well

as

the

date

of

purchase

and

the

dealer

from

whom

it

was

purchased.

In

the

event

the

unit

must

be

returned

to

our

factory

for

service,

you

will

be

instructed

on

the

proper

procedure

when

you

call

or

write

for

a

Return

Authorization

UNDER

NO

CIRCUMSTANCES

SHOULD

YOUR

UNIT

BE

SHIPPED

TO

OUR

FACTORY

WITHOUT

PRIOR

AUTHORIZATION.

If

the

original

shipping

carton

and

its

fillers

have

been

lost,

discarded,

or

damaged,

a

duplicate

carton

may

be

obtained

from

our

Service

Department

for

a

nominal

charge

Always

ship

PREPAID

VIA

UNITED

PARCEL

SERVICE

(UPS)

OR

OTHER

APPROVED

CARRIER.

DO

NOT

SHIP

VIA

PARCEL

POST,

since

the

packing

was

not

designed

to

withstand

rough

Parcel

Post

handling

FREIGHT

COLLECT

SHIPMENTS

CAN

NOT

BE

ACCEPTED

UNDER

ANY

CIRCUMSTANCES.

5

GFA-5802

SPECIFICATIONS

Power

Rating

(To

FTC

Requirements)

300

watts

continuous

average

power

into

8

ohms:

20Hz

and

20kHz

with

both

channels

driven

at

less

than

0.18%

THD

450

watts

continuous

average

power

into

4

ohms:

20Hz

and

20kHz

with

both

channels

driven

at

less

than

0.18%

THD

IM

Distortion

(SMPTE)

1

watt

to

300

watts

into

8

ohms.

<

o.075%

1

watt

to

450

watts

into

4

ohms.<

o.075%

IM

Distortion

(CCIF,

Any

Combination

from

4kHz

to

20kHz)

300

watts

into

8

ohms...

<0

075%

450

watts

into

4

ohms.

<

q

075%

THD

+

Noise

at

300

watts

into

8

ohms

(Typical)

20Hz

.

0.015%

1kHz

.

0.02%

10kHz

0.09%

20kHz

.

0.15%

THD

+

Noise

at

450

watts

into

4

ohms

(Typical)

20Hz.

1kHz.

10kHz.

20kHz.

0.025%

0.025%

.

0.09%

.

0.15%

Frequency

Response

@

1

Watt

into

8

ohms

(10Hz

to

20kHz).

+

0,

-0.25dB

Power

Bandwidth

(-3dB).

3

H

z

to

130kHz

Dynamic

Headroom

into

4

ohms

2.3dB

Signal

to

Noise

Ratio,

“A”

Weighted

(300

watts

onto

8

ohms)

.>

105dB

Gain

29

dB

Input

Impedance

Unbalanced.105Kohms

Balanced

(bridged).

10K

ohms

Input

Sensitivity

for

1

Watt

output.0.1

volts

for

300

Watts

output.

1.7

volts

Rise

Time

(5kHz,

90

V

peak-to-peak

square

wave,

20%

to

80%).

2

.

2

5

pS

Power

Consumption

(Continuous,

Both

Channels

Driven)

Quiescent.

540VA

Maximum.

1440VA

300

watts

into

8

ohms.

1340VA

Power

(Available

in

230VAC

by

special

order).

Chassis

Dimensions.

Maximum

Dimensions.

Weight.

Weight,

Packed.

ADCOM©

11

Elkins

Road

.

15VAC

-

50/60Hz

.

137/e”

(mm)

x

17”

(432mm)

x

8”

(mm)

ISYz"

(mm)

x

17”

(432mm)

x814

"

(mm)

.

48

lb.

(kg)

.

55

lb.

(kg)

East

Brunswick,

NJ

08816

U.S.A.

Tel:

(972)

or

(908)

390-1130

♦

Fax:

(972)

or

(908)

390-9152