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1.25 amps. Do not substitute a larger value fuse. Contact First Watt if you have
any questions.
The amplifier can be run in three configurations. There is one way to use the
amplifier in stereo. There are two ways you can run the amplifier as a mono-
block, either by paralleling the inputs and outputs for more current and less
distortion, or by driving the two channels from a balanced source.
I'm assuming that you know how to attach the speaker cables to the 5 way output
connectors provided. Please make all the connections with the amplifier power
switch in the OFF position.
Stereo Operation
For two channel operation, input signal is connected to the RCA inputs, ignoring
the XLR input. (Unlike some other designs from First Watt or Pass Labs, there
are no jumpers on the unused XLR inputs.) The output connections to the
loudspeakers are made through the gold plated brass 5 way connectors. The red
(top) connection is positive and the black (bottom) is negative. In this amplifier the
black banded output connectors are connected directly to signal ground.
Mono Balanced Operation
In mono balanced operation, you can achieve up to 100 watts output into an 8
ohm load. The amplifier is driven by a balanced source, either through the two
RCA inputs or the balanced XLR connector. The left channel (as seen from the
front) is presumed to have the positive phase, so the positive input appears either
on the left channel RCA or Pin 2 of the XLR connector. The right channel gets the
negative phase input on its RCA or on Pin 3 of the XLR connector.
Pin 1 of the XLR connector is ground
Pin 2 is positive.
Pin 3 is negative.
If you look carefully at the connector you will see tiny labels next to the pin holes.
No jumpers or shorting plugs are necessary.
The output to the speakers occurs through the top red banded brass connectors
on the two output 5 way binding posts. The left channel (as seen from the front)
has the positive output, and the right channel has the negative. The bottom black
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