Adcom GFA-7300 User Manual
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details you can hear
GFA-7400
s,
GFA-7300
High Current
5-Channel
Power Amplifiers
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
A
DO NOT OPEN
AVIS. RISQUE DE CHOC ELECTRIQUE-NE PAS OUVRIR
The graphic symbol ot 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 gam 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
H
ATTENTION
POUR PREVENIR LES CHOCS ÉLECTRIQUES NE PAS UTILISER
CETTE FICHE POLARISÉE AVEC UN PROLONGATEUR, UNE PRISE
DE COURANT OU UNE AUTRE SORTIE DE COURANT, SAUF SI LES
LAMES PEUVENT ÊTRE INSÉRÉES À 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
Any outdoor antenna must be located away from all power lines.
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
Nationai 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 (j).
EXAMPLE OF ANTENNA GROUNDING AS PER NATIONAL ELECTRICAL CODE INSTRUCTIONS
CONTAINED IN ARTICLE 810 - RADIO AND TELEVISION EQUIPMENT
POWER LINES
STANDOFF
INSULATORS, b
ANTENNA
LEAD-IN WIRE
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 ram, 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.
TO EXTERNAL ANTENNA
POWER SERVICE GROUNDING
ELECTRODE SYSTEM
(e g interior metal water pipe)
BONDING JUMPER, d
OPTIONAL ANTENNA GROUNDING
ELECTRODE DRIVEN 8 FEET (2 44 M) INTO
THE EARTH IF REQUIRED BY LOCAL
CODES SEE NEC SECTION 810-21 (f)
TERMINALS OF RADIO RECEIVER
GROUND WIRE, a.b
GROUND CLAMPS
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
TABLE OF CONTENTS
SAFETY INFORMATION.............................................1
INTRODUCTION
WARRANTY INFORMATION.........................................2
DESCRIPTION OF UNIT
FEATURES GFA-7400...................................................3
FEATURES GFA-7300...................................................3
INSTALLATION & HOOKUP
UNPACKING THE GFA-7400/7300
PLACING THE GFA-7400/7300.....................................4
QUICK CONNECTION...................................................5
CONNECTION DIAGRAM..............................................6
INPUTS AND OUTPUTS
CARING FOR YOUR GFA-7400/7300
...............................................
OPERATION
INPUTS AND OUTPUTS
FUSES AND AC SUPPLY
LED DISPLAYS.......................................................12-13
...............................................
......................................
TROUBLESHOOTING
RESOLVING PROBLEMS
SERVICE INFORMATION............................................16
SPECIFICATIONS
..................................................
......................................
...............................
...........................
10-11
14-15
17-18
4
7
8
9
INTRODUCTION
Congratulations on your decision to purchase the GFA-7400 or GFA-7300 5-channel power
amplifier. The GFA-7400 and GFA-7300 have been designed to be high performance and
musically accurate in a configuration specifically designed to integrate with any home theater
processor. You have made a wise choice that will reward you for years to come with exceptionally
accurate and musical sound reproduction. To realize the full potential of your new amplifier, and
before making any connections to it, please read these operating and installation instructions
thoroughly.
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. Always retain your original sales receipt as a proof of purchase.
GFA-7400 FEATURES
Precision-matched devices used throughout the signal path.
100,000 pF of power supply-filter capacitance for greater reserve capacity.
Independent power supplies for each channel.
Fewer gain stages improve signal reproduction accuracy.
Custom toroidal power transformer provides better regulation and greater peak
current capability.
Independent thermal-overload and distortion LEDs for all 5 channels.
High quality, gold-plated 5-way binding posts.
High quality, gold-plated RCA jacks.
Large independent internal heatsinks for greater cooling capability of output
devices.
Convenient 12 VDC power ON/OFF triggering.
Heavy gauge, anodized aluminum front panel.
Powder-coated, baked chassis and top cover for greater durability.
Cooling vents for greater efficiency and cooler operation while driving low
impedance loads.
Made in the USA
GFA-7300 FEATURES
Precision-matched devices used throughout the signal path.
47,00j0 pF of power supply-filter capacitance for greater reserve capacity.
Independent power supplies for each channel.
Fewer gain stages improve signal reproduction accuracy.
Custom toroidal power transformer provides better regulation and greater peak
current capability.
Independent thermal-overload and distortion LEDs for all 5 channels.
High quality, gold plated binding posts.
High quality, gold-plated RCA jacks.
Large independent, internal 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 for greater efficiency and cooler operation while driving low
impedance loads.
INSTALLATION & HOOKUP
UNPACKING THE GFA-7500 and GFA-7300
Before your new ADCOM amplifier 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-7400/7300,
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.
PLACING THE GFA-7400/7300
During normal home operation the internal heatsinks of the GFA-7400/7300 may become
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-
7400/7300 should be kept away from external sources of heat such as radiators and hot-air
ducts. The GFA-7400/7300 should never be placed with other heat-producing components
in a cabinet or enclosure lacking free air flow. 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 imperative that these vents are not obstructed in any way.
We recommend that you do not stack other components on top of the GFA-7400/7300.
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-7400/7300, but the free flow of air through the ventilating
slots in the amplifier may be partially obstructed.
If you observe these recommendations, the GFA-7400/7300 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, panels and around the ventilating slots should be all that is required.
The optimal performance of your new GFA-7400/7300 will ultimately depend on the care
with which you make the connections between the amplifier, preamplifier, surround sound
decoder 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 Inputs and
Outputs section of CONNECTING THE GFA-7400/7300.
NOTE! Product shown is for reference only, The GFA-7400 and GFA-7300 differ in
appearance but have the same basic configuration.
CONNECTING THE GFA-7400/7300
Remember, that the Left and Right designations are as you are sitting down in your
listening/viewing area. On the rear panel, the inputs and outputs are grouped in 5 bracketed sets,
one for each channel. They are as follows:
GFA-7300 GFA-7400
RR (Right Rear) ............................... Surround Right (SR)
LR (Left Rear)................................... Surround Left (SL)
FR (Front Right)
...............................
Front Right (FR)
C (Center)......................................... Center (C)
FL (Front Left)
..................................
6
Front Left (FL)
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