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Operating Your HCA-1205A or HCA-1203A
Power Switch
Manual Turn On
Press the upper side to turn the unit on manually; press the lower side to turn the unit off.
Automatic Turn On
When the power switch is in the off position, the power amplifier can be turned on with an external
DC voltage applied at the DC trigger connector on the rear panel.
AC Line LED
The AC line LED on the front panel of your amplifier will illuminate whenever AC is present at the
AC connector. This LED indicates that the AC cord is connected and that power is currently applied
to the amplifier.
Standby/Normal Operation LEDs
The red Standby LED will light when the amplifier is turned on either with the power switch or an
external DC trigger. It will stay lit about four to five seconds while the amplifier circuits stabilize.
After that, the red LED will turn off and the green normal LED will signal that the protection relays
have switched off and that amplifier is ready to operate.
The Standby LED will also light whenever there is a short circuit or other fault that triggers the
protection circuitry. This may indicate one of the following conditions: DC present at the amplifier's
input, a speaker impedance overload, a short circuited speaker line, or possible internal fault. If this
LED remains lit, remove power to the amplifier and check all connections. During this time, the
protection circuits should automatically reset. If the red LED stays lit after you reapply power,
contact your Parasound Dealer, Installer or Parasound Technical Service for further advice.
Current Overload LEDs
The Current Overload LEDs for left and right channels will only illuminate if the unit is driven past
its maximum current capacity. These LEDs are not clipping indicators, but rather are designed to
signal when you are exceeding the limits of your amplifier. If these LEDs light, it’s usually a sign
that your speaker impedance is too low, resulting in too much current draw from the amplifier's
power supply. In virtually all imaginable listening situations with recommended loads, these LEDs
should never illuminate.
Level Controls
Each channel has its own rear mounted "set and forget" input level control. Your amplifier sounds
best with these level controls set to maximum, where they are effectively out of the audio signal path.
However, if your preamplifier has very high gain, and its volume control cannot track properly for
left-right channel balance near its minimum position, it may be necessary to reduce the input level
control settings on the amplifier. When using the HCA-1205A in a THX installation, each level
control must be set at maximum to correspond to 0 dB THX reference level.
