Amplifier Tech AT1800 Series Stereo Amplifier User Manual

Connecting Your Amplifier
When making connections between any source components
and the amplifier, or when making connections to any speaker,
be certain that both the input devices and the amplifier are
turned off. To assure that there will be no unwanted signal
transients that can damage equipment or speakers, it is always
best to unplug all equipment before making any connections.
Input Connections
Connecting the amplifier to your source equipment is simple.
Using high-quality audio interconnect cables, match the
output channel designations on the rear of your source
equipment to the input jacks on the rear panel of your
amplifier that have the same channel name. When making
connections with RCA type plugs on interconnect cables,
make certain to gently, but firmly, insert the plug into the
jack. Loose connections can cause intermittent sound and
may damage your speakers. Some quality RCA plugs may be
very tight, and it is important to assure a proper connection
between the interconnection cable and the input jack.
Speaker Connections
To assure that the high quality signals produced by your
amplifier are carried to your speakers without loss of clarity
or resolution, we recommend that you use high quality
speaker wire. Many brands of wire are available; the choice
may be influenced by the distance between your speakers
and the amplifier, the type of speakers you use, personal
preferences, or other factors.
Regardless of the brand or type of speaker wire selected, we
recommend that you use a wire constructed of fine,
multi-strand copper with a gauge of 14 or less. In specifying
wire, the lower the number, the thicker the cable. Wire with
a gauge of 16 may be used for short runs of less than twenty
feet. We do not recommend that you use any wires with an
AWG equivalent of 18 or higher due to the power loss and
degradation in performance that will occur.
To connect the amplifier to your speakers, a pair of binding
posts is provided for each channel output. These posts will
accept bare wire, spade lugs or banana type plugs. If bare
wire is used for the connections, strip approximately 1/2 inch
to 3/4 inch of insulation from the end of each wire and
carefully twist the strands of each conductor together.
Be careful not to cut the individual strands or twist them off.
All strands must be used for optimal performance.
Correct polarity connections are important to maintain
proper speaker phasing. When speaker phasing is correct, all
speakers move in and out at the same time, preserving the
imaging of the program material. Out-of-phase connections
mean that some speaker cones will be moving in, while others
move out. This will cause indistinct or confused imaging, and
muddled and cloudy sounds. To avoid incorrect phasing or
polarity, be certain to use wire that has distinct markings,
colors, stripes, wording, or grooves on each side of the
speaker cable. When making connections to the amp and
speakers, adhere to a consistent pattern of using one side of
the wire to the red terminals and the other side to the black
terminals. When using cable with markings on one side only,
traditional convention is to consider the marked side of the
wire as the red, or positive (+) connection, and the non-marked
side as the black or negative (–) connection.
Next, loosen the knobs of the amplifier’s speaker output
terminals, far enough so that the pass through hole is revealed.
Follow the proper connection instructions for your system
with regard to which terminals are used. Once the connections
are made, twist the cap back so that the connection is secured,
but do not over tighten or use tools, as this may break the
delicate wire strands and decrease system performance.
If you are using spade lugs, connect them to the speaker wire
using the manufacturer’s instructions, and then loosen the
caps on the speaker terminals. Place lugs between the plastic
cap and the back of the terminal. Be sure to observe proper
polarity, using the appropriate speaker hook-up icons for
your system’s configuration. Using your fingers, tighten to
obtain a positive contact.
When using banana plugs, connections may be made by simply
inserting the jack affixed to your speaker wire into the hole
provided on the rear of the colored screw caps on the binding
posts. Before using banana type jacks, make certain that the
plastic screw caps are firmly tightened down by turning them
in a clockwise direction until they are snug against the chassis.
This will insure that the maximum surface area of the plug is
in contact with the jack. Be certain to observe proper polarity.
Run the cables to the speaker locations. Do not coil any excess
cable, as this may become an inductor that creates frequency
response variations in your system. Finally, connect the wires
to the speakers, again being certain to observe proper polari-
ty. Remember to connect your negative, or black wire, to the
matching terminal on the speaker. The positive, or red wire,
should be connected to the matching terminal on the speaker.
NOTE: While most speaker manufacturers adhere to an industry
convention of using red terminals for positive connections and black
terminals for negative, some manufacturers may vary from this
configuration. To assure proper phase connections, and optimal
performance, consult the identification plate on your speaker
terminals, or the speaker’s manual to verify polarity. If you do not
know the polarity of your speaker, consult the speaker’s
manufacturer for further information.
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