Adcom GFA-7700 V1, GFA-7700 User Manual

GFA-7700

High Current

5-Channel

Power Amplier

Owner’s Manual

GFA-7700 Features

• Precision-matched devices used throughout the signal path.

• 120,000 µF of power supply-lter 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 efciency and cooler operation while driving low impedance loads.

• Standard DB-25 connector to simplify installation

Table of Contents

Introduction

Warranty Information ....................................................................... 2

Description of Unit

Rear Panel..................................................................................... 5

Front Panel.................................................................................... 7

Installation & Hookup

Unpacking the GFA-7700 .................................................................... 9

Placement of the GFA-7700 ................................................................ 9

Quick Connection Diagram ................................................................. 10

Connecting the GFA-7700 ................................................................... 11

Caring for your GFA-7700 ................................................................... 12

Troubleshooting

Resolving Problems .......................................................................... 13

Service Information.......................................................................... 14

Specications ................................................................................. 15

Dolby ProLogic™ and Dolby Digital™ are registered trademarks of Dolby Laboratories Licensing Corp.

Introduction

Congratulations on your decision to purchase the GFA-7700, 5-channel power amplier. The GFA-7700
integrates very well with any other home theater system, such as Dolby ProLogic™ or Dolby Digital™.
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 amplier, please read these
operating and installation instructions thoroughly before attempting to make any connections to it.

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 benets. 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.

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(1)(3)

(2)

(4a) (4b) (5)

Description of Unit

Rear Panel

Inputs (1)

The audio inputs for the GFA-7700 are through high-quality, gold-plated RCA jacks to minimize high­frequency losses, noise, etc. They will accept standard RCA-type plugs, one for each of the ve
channels; Front L (Left), Center, Front R (Right), Surround L (Left), and Surround R (Right). To insure
that the performance designed into the GFA-7700 is preserved, you should use the highest quality
audio cables possible. There are many cables which are color-coded and specically designed for this
application. Your Adcom dealer can help select the best cable for your needs. (See Connecting the

GFA-7700 for more information.)

Outputs (2)

The GFA-7700’s connections to the loudspeakers are made through high-grade, 5-way, gold-plated
binding post terminals. There are two terminals for each speaker, which are colored RED for the
positive (+) output and BLACK for the negative (-) output.

The binding posts will accept a variety of connector types; the most secure and prevalent of these is
the “U”-type spade connectors (at least 0.25” wide and maximum width of 0.57”). The terminal will
also accept bare wire (up to AWG10) and “banana” type plugs (single or dual.) (See CONNECTING THE
GFA-7700 for more information)

DB-25 Multichannel Audio Input Connector (3)

Input connections may be made with the optional DB-25 computer-type connector. Using this type of
connecting cable would override the need to use the RCA-type inputs (1). This mode of connection
retains the same high level of signal transfer, simplies the job signicantly and insures automatic,
correct connections to all channels.

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