Adcom GFP-750 User manual

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>DCOM

details

you

can

hear

GFP-750

Stereo

Preamplifier

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.

CAUTION

RISK

OF

ELECTRIC

SHOCK

DO

NOT

OPEN

AVIS:

RISOUE

DE

CHOC

ELECTRICUE-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.

O

n

l

y

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

POLARI3EE

AVEC

UN

PROLONQATEUR,

UNE

PRISE

DE

COURANT

OU

UNE

AUTRE

SORTIE

DE

COURANT,

SAUF

SI

LES

LAMES

PEUVENT

ETRE

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^')

copper,

No.8

AWG

(8.4

mm^)

aluminum,

No.

17

AWG

(1.0

mm")

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")

copper,

or

the

equivalent,

when

a

separate

antenna-grounding

electrode

is

used.

See

NEC

Section

810-21

(]).

EXAMPLE

OF

ANTENNA

GROUNDING

AS

PER

NATIONAL

ELECTRICAL

CODE

INSTRUCTIONS

CONTAINED

IN

ARTICLE

810

-

RADIO

AND

TELEVISION

EQUIPMENT.

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.

1.

PRODUCT

DESCRIPTION

1.1.

GFP-750

Front

Panel

Diagram

&

Remote

Control

Stereo/Reverse/Mono

Switch

(reverse)

or

combine

(mono)

channels

Input

Source

Selection

Select

input

source

®

Passive

Mode

On/Off

Bypass

active

gain

stages

Power

On/Off

Turn

unit

on

and

off.

©

External

Processor

Engage

external

processor

©

Balance

Control

Adjust

balance

level

©

Infrared

Remote

Control

Sensor

Lens

Receiver

for

remote

control

IR

signal

©

Volume

Control

Adjust

volume

level

©

Mute

Engage

Mute

circuitry

1.2.

GFP-750

Rear

Panel

Diagram

@

CD

Balanced

Inputs

^l)

Gold

Jumpers

@

Unbalanced

Stereo

Inputs

@

Tape

Loop

Stereo

In/Out

@

External

Processor

Loop

Stereo

In/Out

@

Main

1

and

Main

2

Unbalanced

Stereo

Outputs

@

Main

3

Balanced

Stereo

Outputs

(T^

Remote

Control

Infrared

repeater

outputs

(x

2)

(18)

Remote

Control

Sensor

Input

Master

On/Off

Switch

@

AC

Power

Cord

Socket

@

Switched

AC

Outlet

2

1.3.

Product

Features

©

©

®

©

©

©

©

©

d

Stereo/Reverse/Mono

Switch

This

switch

is

used

to

change

the

polarity

of

the

input

signal

in

relation

to

the

output

signal.

The

stereo

setting

allows

normal

playback

of

the

input

signal.

The

reverse

setting

Inverts

the

phase

of

the

input

signal.

The

mono

setting

combines

both

channels

for

a

monaural

input

signal

or

where

speaker

placement

does

not

accommodate

stereo

playback.

Input

Selection

The

input

selection

knob

has

a

digital

interface

that

senses

movement

of

the

knob.

The

knob

appears

to

turn

freely

as

the

interface

detects

the

direction

the

knob

is

being

turned

and

indexes

through

the

input

sources

accordingly.

To

go

from

aux

2

to

tuner

or

from

tuner

\o

aux

2,

you

must

index

back

through

the

other

input

sources.

Passive

This

features

allows

the

active

gain

stages

of

the

preamp

to

be

bypassed.

(A

slight

drop

in

volume

level

is

expected

when

this

feature

is

engaged.)

This

feature

has

no

effect

when

the

processor

feature

is

en¬

gaged.

Power

On/Off

The

GFP-750

is

turned

on

by

pressing

either

the

remote

control

power

button

or

toggling

the

front

panel

power

switch.

The

LED

above

the

power

switch

will

come

on

indicating

the

unit

is

on.

(The

power

status

LED

will

glow

slightly

dimmer

when

the

unit

is

muted.)

Processor

Switch

Engages

the

processor

loop

when

activated.

See

@

for

further

information.

Balance

Control

The

GFP-750

balance

control

feature

provides

finer

balance

adjustment

allowing

for

greater

balance

accuracy

and

will

not

entirely

mute

either

channel.

Infrared

Remote

Control

Sensor

Lens

This

lens

protects

the

infrared

receiver

which

receives

commands

from

the

remote

control.

The

pathway

between

the

lens

and

remote

control

must

be

free

of

obstructions

for

the

remote

control

to

operate

the

GFP-750.

Volume

Control

The

front

panel

volume

control

knob

is

motorized.

It

may

be

adjusted

either

by

hand

or

by

the

volume

buttons

on

the

remote

control.

The

volume

knob’s

groove

always

indicates

the

present

volume

level.

The

volume

control

knob

may

be

used

to

reduce

the

volume

level

while

the

GFP-750

is

muted

without

deac¬

tivating

the

mute

feature.

Mute

The

GFP-750's

mute

feature

is

engaged

by

pressing

the

mute

button

on

the

remote

control.

This

feature

fully

mutes

the

outputs.

To

deactivate

the

mute

feature,

press

the

mute

button

again

or

either

of

the

two

volume

buttons

on

the

remote

control.

(Turning

the

front

panel

volume

knob

will

not

deactivate

the

mute

feature.)

Balanced

CD

Inputs

Before

using

the

balanced

CD

inputs,

it

is

necessary

to

remove

the

gold

jumpers

located

between

pins

1

and

3

in

both

connectors.

(See

the

figure

to

the

right.)

When

switching

from

balanced

CD

inputs

to

unbalanced

CD

inputs,

you

must

replace

the

jumpers

between

pins

1

and

3

as

shown.

|l

DO

NOT

USE

BOTH

BALANCED

AND

UNBALANCED

CD

INPUTS

AT

THE

SAME

Time.

l|

_

Gold

Jumpers

^

When

using

the

unbalanced

CD

inputs,

jumpers

must

be

installed

to

short

pins

1

and

3

of

the

to

balanced

input

jacks.

^

Unbalanced

Stereo

Inputs

gold

jumpers

Connect

the

various

outputs

from

each

signal

source

to

these

unbalanced

stereo

inputs.

Do

not

connect

both

the

unbalanced

and

balanced

CD

inputs

at

the

same

time.

See

the

section

labeled

CONNECTIONS

for

further

information

regarding

these

inputs.

3

@

Tapeln/out

The

tape

outputs

are

fixed

level

outputs.

The

signal

is

selected

by

the

input

source

knob

or

input

buttons

on

the

remote

control.

{The

tape

outputs

are

muted

when

tape

is

selected

as

the

input

source

or

when

the

processor

loop

is

engaged.)

@

Processor

The

processor

in/out

connectors

allow

for

convenient

connection

of

an

external

processor,

like

ADCOM’s

GSA-700

surround

sound

processor.

The

connection

diagrams

under

Audio/Home

Theater

and

Multi-

Channel

Audio

detail

basic

connection

methods

that

take

advantage

of

this

feature.

When

the

processor

feature

is

activated

the

external

processor

controls

the

volume

and

balance

of

the

system.

@

Main

Unbalanced

Stereo

Outputs

Main

1

is

an

unbalanced

line

level

stereo

output

to

be

connected

to

the

amplifier’s

unbalanced

inputs.

Main

2

accommodates

a

second

amplifier

for

multi-room

or

multi-zone

operation.

@

Main

Balanced

Stereo

Outputs

Main

3

is

a

balanced

line

level

stereo

output

for

use

with

amplifiers

that

utilize

balanced

inputs.

©

Remote

Control

Infrared

Repeater

Output

Connect

the

ACCOM

IRA-50011

infrared

repeater

to

control

other

remote

controlled

equipment

via

the

remote

sensor

extension.

®

Remote

Control

Sensor

Input

Connect

either

the

ACCOM

XR-500II

or

SPM-500II

to

extend

the

remote

control

capabilities

of

the

GFP-

750

via

an

external

room

or

zone.

®

Master

On/Off

Switch

The

rear

panel

Master

On/Off

Switch

allows

the

unit

to

be

electrically

disconnected

from

the

AC

power

source

without

having

to

remove

the

AC

power

cord.

We

recommend

the

Master

On/Off

switch

be

pushed

to

the

“O”

(off)

position

when

the

unit

will

be

left

unat¬

tended

for

an

extended

period

of

time.

IF

THE

GFP-750

DOES

NOT

RESPOND

TO

REMOTE

CONTROL

COM¬

MANDS,

AND

THE

AC

POWER

CORD

IS

INSTALLED,

CHECK

THAT

THE

MASTER

ON/OFF

SWITCH

IS

IN

THE

“I”

ON

POSITION.

2.2.

Adding

an

External

Processor

Note:

These

diagrams

represent

a

basic

audio/video

system

using

the

GFP-750

with

various

other

audio

equipment.

Additional

audio

and

video

sources

may

easily

be

added

to

the

system

following

similar

connections

as

shown.

Refer

to

your

other

owner's

manuals

for

more

detailed

connection

information.

5

3.

TROUBLE

SHOOTING

Symptoms

Possible

Causes

Unit

does

not

respond

to

front

panel

-AC

power

cord

not

connected

power

switch

or

remote

control

power

-Master

On/Off

switch

is

off

button.

Power

LED

is

dimmer

than

the

other

-Preamp

is

muted.

(Power

LED

is

dimmed

when

outputs

are

muted.)

status

LED’s.

No

signal

at

main

outputs

-Wrong

source

selected

-The

external

processor

feature

is

activated

{processor

LED

is

on)

without

the

external

processor

either

being

on

or

connected

properly.

(The

main

outputs

are

connected

to

the

processor

in

inputs

when

in

the

external

processor

feature

is

activated.)

-Preamp

is

muted.

(Power

LED

Is

dimmed

when

outputs

are

muted.)

No

signal

at

tape

outputs

Volume

level

is

reduced

when

going

to

passive

mode

-The

input

device

is

on

tape.

-The

external

processor

feature

is

activated.

(Processor

LED

is

on)

{tape

out

is

disconnected

when

tape

is

selected

as

the

source

or

the

processor

feature

is

activated.)

-A

slight

reduction

in

volume

level

is

to

be

expected

as

the

active

gain

stages

are

bypassed

when

the

passive

feature

is

engaged.

The

volume

and

balance

controls

do

not

function.

-The

volume

and

balance

controls

are

bypassed

when

the

processor

feature

is

engaged.

Either

use

the

controls

on

the

external

processor

or

switch

the

processor

feature

off.

4.

CARE

AND

MAINTENANCE

The

GFP-75(Ts

steel

chassis

and

extruded

aluminum

front

panel

are

specially

coated

to

provided

a

durable

and

attractive

finish.

To

remove

dust

and

finger

smudges,

merely

dampen

a

cloth

and

wipe

off

the

chassis.

Do

not

use

strong

solvents

or

detergents.

Many

are

very

abrasive

or

corrosive.

Never

spray

or

pour

any

liquid

<^to

the

chassis

or

front

panel.

In

the

event

of

any

liquid

getting

Into

the

chassis,

unplug

the

unit

from

the

AC

outlet

immediately.

5.

SERVICING

ACCOM’s

Technical

Service

Department

will

be

happy

to

answer

all

questions

pertaining

to

the

installation

and

operation

of

your

unit.

In

the

unlikely

event

of

difficulty,

please

contact

us

for

prompt

advice.

If

we

cannot

help

you

resolve

the

problem

Immediately,

we

may

refer

you

to

an

authorized

repair

agency,

or

authorize

the

return

of

your

unit

to

our

plant.

All

written

inquiries

should

be

addressed

to:

ADCOM

Service

Department

10

Timber

Lane

Marlboro,

NJ

07746

USA

(732)

683-2356

Phone

(732)

683-9792

Fax

Telephone

inquiries

are

welcome

from

Monday

through

Friday

between

9

AM

and

4

PM,

Eastern

Standard

Time.

We

will

also

be

glad

to

answer

any

FAX

inquiries.

Please

Include

your

phone

and

FAX

numbers

so

we

can

respond.

When

inquiring

about

your

unit,

please

include

the

serial

number,

the

name

of

the

dealer

from

whom

you

pur-

Chased

the

unit,

and

the

date

of

purchase.

If

we

ask

you

to

return

the

unit

to

us

for

service,

we

will

issue

a

specific

Return

Authorization

UNDER

NO

CIRCUMSTANCES

SHOULD

THE

UNIT

BE

SHIPPED

TO

US

WITHOUT

PROPER

AUTHORIZA¬

TION

OR

PACKED

IN

ANYTHING

OTHER

THAN

ITS

ORIGINAL

PACKING.

If

the

original

packing

has

been

lost,

discarded

or

damaged,

we

will

gladly

supply

replacement

packaging

at

a

nominal

charge.

Please

mention

your

need

when

you

contact

us.

i

quid

Always

ship

PREPAID

via

UPS

(United

Parcel

Service)

or

other

appropriate

earner.

FREIGHT

COLLEO

l

bMiH-

MENTS

WILL

BE

REFUSED.

^

^

o

♦

i

DO

NOT

SHIP

VIA

PARCEL

POST

as

the

packaging

will

not

necessarily

withstand

the

handling

by

our

h’ostai

Service.

6

6.

GFP-750

SPECIFICATIONS

Output

Level

(Rated)

i

.ov

THD+N

@

Rated

Output

(20Hz

to

20kHz)

Balanced.<0.025%

Unbalanced.:.<0.095%

THD-t-N

@

Rated

Output

(1kHz)

Balanced.<0.015%

Unbalanced.<0.017%

Output

Impedance

Balance.<1200Q

Unbalanced

Outputs.

<

GOOCl

Input

Impedance

Balanced.94kQ

Unbalanced.47kli

Frequency

Response

(Balanced

and

Unbalanced)

20Hz

to

20kHz.+0,

-0.25dB

IM

Distortions

(@

Rated

Output)

CCIF

from

4kHz

to

20kHz

(Balanced).

<0.009%

CCIF

from

4kHz

to

20kHz

(Unbalanced).<0,035%

SMPTE

(Balanced).<

0.05%

SMPTE

(Unbalanced).<

0.05%

Signal

to

Noise

Ratio

(Ref.

to

1

volt)

“A”

Weighted

(Balanced).>102dB

“A”

Weighted

(Unbalanced).>102dB

input

Sensitivity

(@

Rated

Output)

Balanced.183mV

Unbalanced.365mV

GENERAL

SPECIFiCATiONS

Power

(available

in

230V

by

special

order)

Power

Consumption.

Chassis

Dimensions.

Maximum

Dimensions.

Weight.

Weight,

Packed.

.

115VAC-50/60HZ

.30

VA

3

1/2”

(89mm)

x

17"

(432mm)

x

11"

(279mm)

4

1/8"

(105mm)

x

17"

(432mm)

x

12”(305mm)

.15

lbs

(6.8kg)

.17

lbs.

(7.7kg)

7