Adcom GSA 700 Owners Manual

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ADCOM®
GSA-700

Surround Sound
Processor/Amplifier

OWNERS MANUAL

Page 2

THE FOLLOWING PRECAUTIONS AND SAFETY INSTRUCTIONS
ARE REQUIREMENTS OF UL AND CSA SAFETY REGULATIONS

Warning: To reduce the risk at tire or electric shock, do not expose
this unit to rain or moisture,

RISK OF ELECTRIC SHOCK '
DO NOT OPEN .

AVIS: FIISOUE DE CHOC ELECTRIQUE-NE PAS OUVRIR

The graphic symbol at a lightning llash With an arrow
pOInI Within a mangle Signifies that there is dangerous
voltage wlII'lln the unit and it poses a hazard to anyone
removmg the cover to gain access to the interior of the
unit Only qualltled service personnel should make
any such attempt.

The graphia symbol of an exclamation polnl within an
equilateral triangle warns a user of the devrce that it is
necessary to refer to the instruction manual and its
warnings for proper operation 01 the unit

Do not place this unit on an unstable cart. stand. tripod,
bracket, or table The unit may tell, causrng serious
injury to a child or adult, and serious damage to the
unit Use only With a cart, stand. tripod, bracket, orfable
recommended by the manutactiirer, or said 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 usrng
this unit

Retain this notice and the owners 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 lollowed

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 oosrtion 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 IS ventilation openings

The unit should be Situated away from heat sources such as radiators, heat
registers, stoves. or otherdevrces (including ampliliers) 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 card should be routed so that It is not likely to be walked
on or pinched. especrallv near the plug, convenience receptacles, or where
the cord exrts from the unit

Clean unit only as recommended in its instruction manual

The power-supply cord of the unit should be unplugged train the wall outlct
when it is to be unused for a long period ol time

Care should be taken so that objects do not fall, and liquids are not spilled,
into the enclosure through any opanlngs

This unit should be sewiced by qualified servrce personnel when
The power cord or the plug has been damaged, or

Obiects have fallen, or liqurd has been spilled, into the unit. or
The unit has been exposed to rain, or howls of any kind, or
The unit does not appear to operate normally, or exhibits a
marked change in performance, or

The devree has been dropped, or the enclosure damaged

"1 Com)

DO NOT ATTEMPT SERVICING OF THIS UNIT YOURSELF.
REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

ATI'ENI10N

POUR PREVENIR LES CHOCS ELECTRIQUES NE PAS UTILISER
CETTE FICHE POLARISEE AVEC UN PROLONGATEUR, UNE PRISE
DE COURANT 0U L_JNE 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 DI: I'ULLV INSERTED TO PREVENT BLADE
EXPOSURE

CAUTION
POWER LINES
Any outdoor antenna must be located away from all power lines.

OUTDOOR ANTENNA GROUNDING

ll an outside antenna is connected to your tumor 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 610 of the
National Electrical Code, ANSI/NFPA No. 704984. provides inlormation with
respect to proper grounding of the meet and supporting structure, grounding
of the lead-in wire to an antenna discharge unit, size at 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.

be Secure antenna lead-in and ground wrroo to house wrth stand-oft

insulators spaced from 4-6 feet (1 .2-1 ,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, Sea NEC
Section 810-21 (j)

EXAMPLE OF ANTENNA GROUNDING AS PER NATIONAL ELECTRICAL CODE NSTRUCTIONS
CONTAINED IN ARTICLE 810 - RADIO AND TELEVISION EQUIPMENT

POWER LINES

SERVICE ENTRANCE
DUCTORS

2,.

STANDOFF
INSULATORS, b

MAST
.-
SERVICE
ENTRANCE
EQUIPMENT

ANTENNA
LEAD-IN WIRE

ANTENNA
DISCHARGE
UNIT. c

to EXTERNAL ANTEMA
rsnmmts o; RADIO RECEIVER
POWER SERVICE GROUNDING
ELECTRODE SYSTEM

(0 9 imenar metal water pipe)

GROUND WIRE. a,b

GROUND CLAMPS
BONDING .lllMPER d
OPTIONAL ANTENNA GROUNDING

ELECTRWE DRIVE 3 FEET (2 M M) NTO

THE EARTH IF REQUIRED BY LOCAL
CODES SEE NEG SECTION 021 if)

NOTE TO CATV SYSTEM INSTALLER

This reminder is provrded to call the CATV system installers attention to
Article 8202 of the National Electrical Code that provrdes guidelines for
proper grounding and, in particular, epccifioe that the cable ground shall be
connected to the grounding system of the building. as close to the paint of
cable entry as practical

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INTRODUCTION

FEATURES:

100 Watt high-current Center-channel amplifier

50 Watts x 2 high-current Rear-channel amplifiers

2 Audio, 2 Video Inputs. 1 Audio, 1 Video Output

Full function Remote Control

On Screen display for most-used iniormation

Dolby Pro Logic, Concert Hall and Night Club soundtields
Adaptable to Dolby Digital® Surround w/cutboard processor
4 independent user-programmable memories

Bass EQ circuit for more dynamic movie soundtracks

\\\\\\\\\

TABLE OF CONTENTS:
INTRODUCTION
Front Panel Diagram
Rear Panel Diagram...
Description of Front Panel Controls.
Description of Rear Panel Controls.
Remote Control Diagram...
Description of Remote Contro u
INSTALLATION
Unpacking .....
Placement .....
Which Configuration to Select
Connection Guidelines
Connection Diagrams.
Additional Connections...
OPERATION
Turning your System On and Off ........
Putting the GSA-700 in the Signal Path .
Saving the Configuration In Memory
Setting the Input Levels..
Setting the Volumes
Setting the Subwoofer .
Choosing a Surround Mode...
Choosing Delay Times ......
Using the Balance Check ..
Using the On Screen Display
MISCELLANEOUS
Troubleshooting
Servicing .......
Specifications

DESCRIPTION OF GSA-700:

Congratulations on your purchase of the GSA-700 Surround Amplifier/Processor. You have made a wise
choice that will bring you years of entertainment.

The GSA-700 is a unique addition to the Home Theater industry, being a 3-channel, high-current. quality
amplifier system combined with a Dolby Pro Logic Processor and including a port to incorporate an Adcom Dolby
Digital© Surround Processor (the GDD-l). The GSA-700 is designed to be added to an existing 2-channel audio
system to convert it into a 5-channel AudioNideo Home Theater Surround System with the convenience of On Screen
display and full-function remote control.

The GSA-700 has 4 independent memories for storing the total configuration, one for each input source. The
configuration includes Input Level, Center Volume, Rear Volume, Subwoofer Volume, Surround Mode, and Delay Time.
Every time you choose an input source, the configuration changes to your specific needs.

This unit is manufactured under license from Dolby Laboratories Licensing Corporation It is additionally licensed
under one or more at the tollcwmg patents: US number 3,959,590: Canadian numbers 1,004,603. 1.037.877
"Dolby, Pro Logic. Dolby Digital" and the double-D symbol ([1]) are trademarks oi Dolby Laboratories Licensmg Corporation

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5-Channel Stereo: This mode makes full use of the home theater's speaker compliment without adding any
processing or delay. This is the only mode where the rear speakers operate in stereo (as opposed to mono). The
center channel speaker will produce a mono (L+Ft) signal, while the left-rear speaker will reproduce the left signal and
the right-rear speaker will reproduce the right signal. By adjusting the center and rear volumes. you can create a
dynamic and complete soundtield without the slight blurring effect of a delay line. There is no delay time to choose in
this mode.

2-Channel Stereo: This is also considered Bypass" mode. The center and rear speakers are turned off, and
the signal is passed through the GSA-700 with no alteration. There is no delay time to choose in this mode.

CHOOSING A DELAY TIME

In addition to adding a sense of spaciousness and ambiance, rear channel time delay serves a specific
purpose in Dolby Pro Logic playback. It prevents us from hearing front channel information, particularly dialog, from the
rear speakers. Based on a psychoacoustical effect called masking", this technique presenres the proper directional
clues intended by the sources producer.

Longer delay periods defeat the masking" effect and create awareness of a growing discontinuity between the
front and rear outputs. Eventually, the rear channel output becomes a discrete echo rather than an integral part of a
coherent soundfield. For this reason, Dolby Pro Logic intentionally limits rear channel time delay to relatively small
amounts.

USING THE BALANCE CHECK

In the Dolby Pro Logic mode, it is important to match the volume settings on all the speakers so that they are
as close as possible. This measurement is usually done with your ears and is an accepted practice, however some
people prefer to use a hand held SPL (sound pressure level) meter for matching levels.

To use the System Balance Check, you must be in Dolby Pro Logic mode and it is recommended that no
source be playing at the time. If you are not in Dolby Pro Logic mode when you run through the Balance Check, the
GSA-700 will automatically revert to Pro Logic mode when the Balanced Check is done. The optimum manner to set
the volume level Is to utilize the remote control and sit in the pnmary listenlng posmon. Press the Bal Qhk button (0) on
the remote. You will notice a waterfall" type sound emanating from the front-left speaker. It will last until you press the
button again, then it will move to the center speaker. Successively pressing of the button will advance the waterfall
noise to the fronteright speaker, then the two rear speakers at the same time. After the rear speakers, pressing the
button again will deactivate the noise. By listening to the relative loudness of each speaker. you may adjust the
independent volumes for the center and the rear speakers relative to the front left and right speakers, by using the Rear
Volume Up/Down (e) and Center Volume Up/Down (0) on the remote control. When you adjust the center or rear
volume, the corresponding Smaker Location LEDs (0) on the front panel will blink slowly many times to indicate the
change. If you have reached the upper or lower limits of the volume range, the LED(s) will blink 3 times rapidly.

If you have to turn the center or rear channels up to full-on and they arent loud enough, you will need to reduce
the preamp's volume as stated in Setting the Volumes" on page 17. Similarly, if the center or rears are too
overpowering, try bringing the preamps volume up. Ideally, similar volumes should be achieved while the center and
rear indicators on the On Screen display are in (or near) the middle of the bar-graph. Repeat the process of setting the
levels until the ideal balance is achieved. Once the system is balanced, it is suggested to mark the preamp's volume
level so that it can be easily accessed again at anytime.

USING THE 0N SCREEN DISPLAY

When the GSA-700 is properly configured and wired to your video monitor (TV), you have the ability to set
relative levels and check all the functions of the unit by utilizing the On Screen display function. This gives you a
complete visual indication of the status of the GSA-700.

By pressing the Display button (0) on the remote control, you can activate the On Screen display function. The
display will replace whatever was on the screen previously. By pressing the Display button (0) again, it will turn this
function off and return your previous screen to view.

Whenever the Master Volume (0 or o) is changed, the Volume Up/Down indicator will reveal that change.
Whenever an input is changed with the Ingut Selector (at or 0), the Input Source indicator will reveal which input was

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