OWNER’S MANUAL GFA-7605 & GFA-7607 Multichannel High-Current Power Amplifiers
WELCOME Dear fellow ADCOM product owner, Welcome to the ADCOM family! For more than twenty years, ADCOM products have delivered excellent performance and value for customers around the world. Our products are designed by our experienced and demanding engineering team, built to the highest standards in our factory, and sold and serviced through dealers, custom installers, and other retailers whose primary goal is your complete satisfaction.
TABLE OF CONTENTS WELCOME . . . . . . . . ................................ 2 SAFETY INFORMATION ........................... 4 DESCRIPTION OF UNIT GFA-7605 FEATURES .............................. 5 GFA-7607 FEATURES .............................. 5 WARRANTY INFORMATION ......................... 5 INSTALLATION & HOOKUP UNPACKING THE GFA-7605/7607 .................. 6 INSTALLING THE GFA-7605/7607 .................. 6 CONNECTING THE GFA-7605/7607 ................. 7 OPERATION FRONT AND REAR PANEL DIAGRAMS ...
N OCK 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.
GFA-7605 FEATURES • Precision-matched devices used throughout the signal path. • 100,000 µF of power supply-filter capacitance to optimize transient response. • 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.
INTRODUCTION Congratulations on your decision to purchase the GFA-7605 or GFA-7607 multichannel power amplifier. The GFA-7605 and GFA-7607 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.
CONNECTING THE GFA-7605/7607 When connecting the amplifier to the loudspeaker, it is vital to maintain proper polarity (positive to positive, negative to negative). On the GFA-7605/7607, the positive terminal is color coded RED and labeled “+,” and the negative is color coded BLACK and labeled “-.” The positive terminal on the speaker will be color coded RED, or will be labeled “+,” “pos,” “positive,” “8 ohms” or “4 ohms.
(1) GFA-7607 REAR PANEL (3) (4) (2) (5) GFA-7607 FRONT PANEL LF C RF RS RB LB LS distortion alert > G thermal protection > (6) (7) (8) F A 7607 (9) (1) Input Jacks (6) On/Off Switch (2) Output Binding Posts (7) Power LED (3) I2V DC Trigger (8) Thermal Protection LEDs (4) AC Fuse (9) Distortion Alert LEDs (5) AC Power Cord 8
DESCRIPTION OF UNIT: REAR PANEL (4) AC Fuse The AC Fuse protects the electronic circuits of the GFA7605/7607. This fuse, normally, will fail only if there is an overload within the GFA-7605/7607. It may, however, fail if the amplifier attempts to deliver very high power into very low-impedance loudspeakers. In either case, BE SURE TO REPLACE THE AC Fuse ONLY WITH AN EXACT REPLACEMENT FUSE.
Since the fuse has a ceramic body and you cannot visually examine the fuse element it is therefore suggested that you replace it with an identical substitute or bring the fuse to your ADCOM dealer so they may check its integrity. To replace the fuse, insert it in the back of the fuse-holder cap. Place the cap into the fuse-holder. Place the screwdriver in the recessed slot, gently press in and turn 1/8-turn clockwise. (5) AC Power Cord The AC cord provides power to operate all the GFA7605/7607’s circuits.
WARNING current phase angle or the reactance of the loudspeakers which the amplifier is driving. Sometimes, when the amplifier is in use, the LEDs may occasionally flicker during high volume listening, particularly if you are driving low impedances. This flickering is no cause for concern. The LEDs are simply warning you that the amplifier is approaching its maximum power output into the particular loudspeakers you are using.
RESOLVING PROBLEMS Use the chart below to solve common situations that don’t require professional attention. If the steps stated in POSSIBLE SOLUTION do not resolve your problem, then please contact your ADCOM Dealer or call the ADCOM Customer Service Department. Any problems not covered here should be brought to the attention of your ADCOM Dealer or ADCOM Customer Service Department. SYMPTOM POSSIBLE REASON POSSIBLE SOLUTION Power LED does not glow. No sound AC Power Cord(s) not plugged in.
CARING FOR YOUR GFA-7605/7607 Great care has been taken by ADCOM to ensure that your amplifier is as flawless in appearance as it is electronically. The front panel is a heavy-gauge, high-grade aluminum extrusion carefully finished and anodized for durability. The chassis, top cover and rear panel are heavy-gauge steel that has been powder coated and baked to ensure a lasting finish.
GFA-7605 SPECIFICATIONS Power Rating (To EIA/CEA-490-A Requirements) 125 Watts continuous average power per channel into 8 ohms at any frequency between 20Hz and 20kHz with all channels driven at less than 1.00% THD. 175 Watts continuous average power per channel into 4 ohms at any frequency between 20Hz and 20khz with all channels driven at less than 1.00% THD. IM Distortion (SMPTE) 1 watt to 125 watts into 8 ohms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GFA-7607 SPECIFICATIONS Power Rating (To EIA/CEA-490-A Requirements) 125 Watts continuous average power per channel into 8 ohms at any frequency between 20Hz and 20kHz with all channels driven at less than 1.00% THD. 175 Watts continuous average power per channel into 4 ohms at any frequency between 20Hz and 20khz with all channels driven at less than 1.00% THD. IM Distortion (SMPTE) 1 watt to 125 watts into 8 ohms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ADCOM A division of Klein Technology Group, LLC 8551 East Anderson Drive, Suite 105 Scottsdale, Arizona 85255 Voice: (480) 607-2277 Fax: (480) 348-9876 http://www.adcom.
