Adcom GSA 700 Owners Manual

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Adcom GSA 700 Owners Manual

Extracted text from Adcom GSA 700 Owners Manual (Ocr-read)


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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

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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 source’s 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 aren’t 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 preamp’s 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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