Adcom High-Current Power Amplifier GFA-555se - Manual (Page 10)

10
DESCRIPTION OF UNIT: REAR PANEL
(1) Inputs (unbalanced)
The audio inputs for the GFA-555se are through
high-quality, gold-plated RCA jacks to minimize
high-frequency losses, noise, etc. They will accept
standard RCA-type plugs, one for each channel; Left and
Right. To insure that the performance designed into the
amp is preserved, you should use the highest quality
audio cables possible. There are many cables which are
color-coded and specifi cally designed for this application.
Your ADCOM dealer can help select the best cable for
your needs. (See CONNECTING THE GFA-555se for more
information).
(2) Inputs (balanced)
The audio inputs for the GFA-555se are through
high-quality, Balanced XLR jacks to minimize
high-frequency losses, noise, etc. They will accept
standard XLR-type plugs, one for each channel; Left and
Right. To insure that the performance designed into the
amp is preserved, you should use the highest quality
audio cables possible. There are many cables specifi cally
designed for this application. Your ADCOM dealer can help
select the best cable for your needs. (See CONNECTING
THE GFA-555se for more information).
(3) Outputs
The GFA-555se connections to the loudspeakers are made
through high-grade, 5-way, gold-plated binding post
terminals. There are two terminals for each speaker,
which are colored RED for the positive (+) output and
BLACK for the negative (-) output.
The binding posts will accept a variety of connector types;
the most secure and prevalent of these is the “U”-type
spade connectors (at least 0.25’’ wide and maximum
width of 0.57”),. The terminal will also accept bare wire
(up to AWG1O) and “banana” type plugs (single or dual).
(Refer to your User Manual for your speakers for additional
information).
(4) AC Fuse
The AC Fuse protects the electronic circuits of the GFA-
555se. This fuse, normally, will fail only if there is an
overload within the GFA-555se. It may, however, fail if the
amplifi er 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. The proper fuse values are:
GFA-555se for 115 volt operation
Fuse Rating
BUSS® Littelfuse®
12 Amp 250 Volt ... AGC-12/250V .... (3AB) 314012/250V
GFA-555se for 230 volt operation
Fuse Rating
BUSS® Littelfuse®
6 Amp 250 Volt .... AGC-6/250V ..... (3AG) 314006/250V
Before attempting to replace a failed fuse, be certain
to unplug the AC Power Cord from the AC wall outlet to
prevent possible electrical shock. Replace the AC Fuse
only with one identical in type and rating as printed on
the rear panel. DO NOT USE ANY SUBSTITUTE FUSES WITH
DIFFERENT RATINGS OR VALUES. Failure to observe this
precaution may cause serious damage to the amplifi er
circuits, may create a hazard fi re, and may void the warranty.
If the Power LED (8) does not glow, it may be an indication
that the AC fuse has blown. If you are not sure, or the
amplifi er displays other symptoms, please consult the
RESOLVING PROBLEMS section on page 12.
Fuse replacement
To remove the fuse-holder cap, you will need a #2 standard
Phillips screwdriver. Place the screwdriver in the recessed
“crosshead” in the cap. Turn the cap counter-clockwise,
until the cap releases out towards you. Grasp the cap with
your fi ngers and pull it completely out. The fuse is inserted
in the back of the cap; gently pull it free.
Since the fuse has a ceramic body, 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 GFA-555se’s
circuits. Its plug can be connected to a standard wall
outlet provided the outlet supplies a voltage compatible
with the power requirements printed on the rear panel of
the GFA-555se.