Adcom GFA-7705 User Manual

Inputs (1)
To preserve the correct effects, be certain to connect the RCA cables to the proper RCA-input
connector. If the cables are color coded, then use this sequence for the connections:
^ ue ..Left Front
fted...Right Front
G feen ...Center
White with Blue Stripe....Left Surround
White with Red Stripe.Right Surround
The recommended maximum RCA cable capacitance should be less than or equal to 30pF per foot
when measured between the two conductors, and less than or equal to 50pF per foot when measured
between one conductor and the shield.
Outputs (2)
NOTE. The GFA-7705/07 is “polarity correct”. That is, it does not invert phase from input to output.
Any positive signals at its inputs will appear as a positive signal at its outputs.
In connecting the amplifier to the loudspeaker, it is vital to maintain proper polarity (positive to
positive, negative to negative). On the GFA-7705/07, the positive terminal is color coded RED and
labeled “+,” and the negative is color coded BLACK and labeled
The positive terminal on the corresponding loudspeaker will be color coded RED, or will be labeled “+,”
“pos,” "positive,” “8 ohms,” or “A ohms.” The negative terminal on the speaker will be color coded
BLACK, or will be labeled “neg,” negative,” “C,” “Common,” “G,” or “ground.”
It is necessary that your speaker cables be terminated with “U”-
the most contact area insuring long-term reliability. The spade
connector should have a maximum width of 0.57 inches and an
opening width of no less than 0.25” (see diagram on right).
type spade connectors. These will give
To properly connect the speaker cable to the binding posts turn the insulated head of the binding post
clockwise until the wire or connector is firmly secured. Finger pressure is sufficient and you should not
use pliers or other tools which could damage or over tighten the binding-post assembly. The binding
posts have been designed in such a way that finger pressure is all that is required to cause a “pinching”
action among the different metal surfaces to ensure proper connection.
It is very important to use the correct size of wire in order to avoid unnecessary loss of amplifier power
in the cable, reduction of amplifier damping factor and other undesirable conditions. Recommended
capacitance of the speaker wire should not exceed 50pF per foot. This insures high frequencies will not
be rolled-off.
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Adcom GFA-7705 Specifications

Power

power rating into 8 ohms	200 Watts continuous average power per channel
power rating into 4 ohms	300 Watts continuous average power per channel
power consumption idle 7 channel	120W

Audio Performance

frequency response at 1 watt into 8 ohms	+0, -0.22dB
power bandwidth	3 Hz to 130kHz
dynamic headroom into 4 ohms	1.90 dB

Electrical Specifications

input sensitivity for 1 watt output	0.1 volts
input sensitivity for 200 watts output	1.40 volts
damping factor (20Hz to 20kHz)	800

Dimensions and Weight

chassis dimensions	8.5” (216mm) x 17” (432mm) x 17.5” (444.5mm)
maximum dimensions	9 3/8” (238mm) x 17” (432mm) x 18.5” (470mm)
unit weight GFA-7707	35.5 kg