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AC Power Connections and AC Grounding
Refer to Figure #1
Before you connect the AC cord, make sure the HCA-2003 power switch is in the off position. If
possible, try to make a direct connection to an AC wall outlet. Do not connect the amplifier to the
accessory AC outlet on your preamplifier or processor. The amplifier's current draw exceeds the ratings of
most preamplifier’s power switches and power cords. If you use an external AC line conditioner or surge
suppressor, make sure it can handle the current draw of the amplifier.
Grounded three pin AC cords are standard on most high end components. However, in some cases, it may
be necessary to "lift" the ground or reverse the polarity of the AC plug to reduce hum. You may use a
3 pin -to- 2 pin AC plug adaptor to lift the AC ground. You will not compromise the sound quality of
your system by lifting the AC ground of your amplifier.
Operating Your HCA-2003
Refer to Figure #2
Power Switch
The upper position of the power switch is on and the lower position is off.
Standby/Operation LEDs
When you first turn the unit on, the red standby LED will illuminate for about four to five seconds while
the amplifier circuits are stabilizing. After that, the red standby LED will extinguish and the green
operate LED will come on to signal that the amplifier is operational.
The red standby LED also illuminates whenever protection circuits are triggered. If this happens, turn the
unit off and remove all connections to the HCA-2003 then turn it back on. If the red LED continues to
glow with no inputs or outputs connected to it, there may be an internal fault. If the green operate LED
comes on with no inputs or outputs connected to it, check for a shorted speaker wire. In rare cases, there
may be DC coming from your preamplifier or processor. Have a qualified technician check for this.
Current Overload LEDs
These LEDs indicate overload of the power supply just before the onset of audible distortion. The current
overload LEDs for channels 1 through 3 will illuminate whenever the corresponding channel is driven
beyond its maximum current capacity. In virtually all listening situations, these LEDs will rarely
illuminate.
Level Controls
Each channel has a separate input level control. If you are using your HCA-2003 in a THX installation,
set each level control at maximum for THX reference level. If you have a non-THX processor or
preamplifier with high gain, it may be necessary to reduce the input level control settings on the
HCA-2003 to allow more range of operation for its volume control. The HCA-2003 level controls are