User manual ADCOM GFA-7700

[. . . ] GFA-7700 High Current 5-Channel Power Amplifier Owner's Manual GFA-7700 Features · Precision-matched devices used throughout the signal path. · 120, 000 µF of power supply-filter capacitance for greater reserve capacity. · Independent power supplies for each channel. · Fewer gain stages improve signal reproduction accuracy. [. . . ] 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. Thermal Protection LEDs (9) The GFA-7700 is provided with both a thermal protection circuit and a current overload circuit which will shut down the individual amplifier's channels if its heatsink temperature reaches 85°C or the amplifier's outputs are shorted. The Thermal Protection LEDs will light when either of these protection circuits are on 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. SAVE ALL PACKING MATERIALS UNTIL THE CLAIM HAS BEEN SETTLED. Placement of the GFA-7700 During normal home operation the internal heatsinks of the GFA-7700 may become warm. However, there are instances during high-level playback into low impedances when the heatsinks will become much warmer than usual. To ensure the amplifier's long-term, trouble-free operation, it is necessary to provide adequate ventilation for the heatsinks. Therefore, the GFA-7700 should be kept away from external sources of heat such as radiators and hot-air ducts. The GFA-7700 should never be placed with other heat-producing components in a cabinet or enclosure lacking free air flow. The top and bottom panels 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-7700. Not only will heat generated by the amplifier affect the performance of equipment stacked on top of the GFA-7700, but the free flow of air through the ventilating slots in the amplifier may be partially obstructed. This is particularly important if your system includes low-impedance loudspeakers which are difficult to drive, or you will consistently demand high volume levels from the amplifier and speaker system. If you observe these recommendations, the GFA-7700 will perform reliably in any reasonable environment. You should also pay attention to such normal considerations as protection from excessive dust and moisture. Occasional vacuuming of accumulated dust on the chassis, panels and around the ventilating slots should be all that is required. The optimal performance of your new GFA-7700 will ultimately depend on the care with which you make the connections between the amplifier, preamplifier, surround sound decoder and the loudspeakers. All input and output signal connections should be made only with high quality, low-loss, low capacitance cables following the recommendations in the Inputs and Outputs section of CONNECTING THE GFA-7700. Quick Connections For those of you who are in a hurry to hook up your amplifier into your system, we have included this quick-connection section. The wiring is straight forward and expeditious if you use the proper cables and follow this diagram exactly. [. . . ] If you have no original copy, please contact your dealer to obtain a duplicate copy. 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. Always ship PREPAID VIA UNITED PARCEL SERVICE (UPS) OR OTHER APPROVED CARRIER. DO NOT SHIP VIA PARCEL POST, since the packaging was not designed to withstand rough Parcel Post handling. [. . . ]