User manual ADCOM GFA-7705

[. . . ] Because ADCOM amplifiers can put out tremendous power, it is particularly important that you connect your amplifier to your pre-amplifier and speakers while the amplifier is unplugged and your other equipment is turned off. This will protect the amplifier and other equipment from potential short circuits that may occur during installion. In addition, it is important that you allow for adequate ventilation around your amplifier and other equipment, since excessive heat buildup can shorten the life of any electronic product, including the amplifier. Once you have correctly connected your pre-amplifier and speakers to your new amplifier, you should be able to enjoy many troublefree years of performance. [. . . ] Therefore, the GFA-7805/7807 should be kept away from external sources of heat such as radiators and hot-air ducts. The GFA-7805/7807 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-7805/7807. 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-7805/7807, but the free flow of air through the ventilating slots in the amplifier may be partially obstructed. Whenever the GFA-7805/7807 is energized the Power LED (7) will glow. To turn the GFA-7805/7807 on, press the push-button. It will remain in the "engaged" position while the unit is energized. To turn the GFA-7805/7807 off, press the push-button in and release and it will move to the "disengaged" position. (2) Outputs The GFA-7805's and GFA-7705's connections to the loudspeakers are made through high-grade, 5-way, gold-plated binding post terminals. 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. If, however, the Distortion Alert LEDs glow brightly or are illuminated most of the time during playback, you are over driving the amplifier and should turn down your volume control to reduce the listening level, otherwise it may cause the Thermal Protection to be activated or, in extreme cases, damage your loudspeakers. (8) Thermal Protection LEDs The GFA-7805/7807 are provided with a thermal protection circuit which will shut down the individual amplifiers if its heatsink temperature reaches 85°C. The Thermal Protection LEDs will light whenever the thermal protection circuit in its respective channel has been triggered and the amplifier is inoperative. The thermal protection circuitry will typically be triggered by very high power demands into impedances much lower than the amplifier is capable of driving at those levels. If any amplifier channel's output through the loudspeaker(s) ceases abruptly, and its Thermal Protection LED glows, you will know that its heatsink temperature has become unacceptably high and the circuitry is protecting the amplification devices. Please note that the Power LED (7) will remain on and the amplifier will still be energized. Once the temperature of the heatsink(s) drops to a safe operating level, that amplifier will automatically resume operation. Activation of the Thermal Protection circuitry in any of the amplifiers in the GFA-7805/7807 is an indication that the amplifier has been over-driven or that the load the loudspeakers are presenting to the amplifier is unreasonably low. If you wish to prevent recurrent activation of the thermal protection circuitry, you must reduce the volume-level demands or correct the load impedance condition which may be causing activation of this circuitry. 9 WHENEVER CONNECTIONS TO OR FROM THE GFA-7805 & GFA-7705 ARE BEING MADE, BE CERTAIN THAT THE AC ON/OFF SWITCH OF THE AMPLIFIER IS IN THE OFF POSITION, THE AC CORD OF THE AMPLIFIER IS DISCONNECTED FROM THE AC WALL OUTLET AND THAT ALL ASSOCIATED COMPONENTS ARE OFF. WARNING Right Back Left Back Left Surround LS unbalanced input input select balanced input LB unbalanced input input select balanced input RB unbalanced input input select balanced input RS unbalanced input input select balanced input RF unbalanced input input select balanced input C unbalanced input input select balanced input LF unbalanced input 12VDC trigger input select balanced input output output output output output output output AC fuse 15ABC 250V 120VAC 50/60 Hz CAUTION please visit www. adcom. com RISK OF ELECTRIC SHOCK DO NOT OPEN WARNING: To reduce the risk of fire or electric shock, do not expose this appliance to rain or moisture. ATTENTION: Pour eviter tout risque de feu ou choc electrique, ` ` ne pas exposer cet appareil a la pluie ou a l'humidite. [. . . ] In any communications to us, please include a daytime phone number where we may reach you. In the event the unit must be returned to our factory for service, you will be instructed on the proper procedure when you call or write for a Return Authorization. UNDER NO CIRCUMSTANCES SHOULD YOUR UNIT BE SHIPPED TO OUR FACTORY WITHOUT PRIOR AUTHORIZATION, OR PACKED IN OTHER THAN ITS ORIGINAL CARTON AND FILLERS. If the original shipping carton and its fillers have been lost, discarded, or damaged, a duplicate carton may be obtained from our Service Department for a nominal charge. [. . . ]