QSC Audio PL230A - Manual (Page 25)

OPERATION
NORMAL OPERATING LEVELS
The amp's protective muting system guards against excessive internal temperatures. With normal ventilation and 4 to 8 ohm loads, the amplifier will handle any signal level including
overdrive. Lower load impedances and higher signal levels produce more internal heating. When using 2 ohm loads, frequent or prolonged clipping may trigger power cutback or
protective muting.
BRIDGE mode doubles the output impedance of the amp; 4 ohms is the minimum load impedance. Heavy clipping may cause muting. If this happens, see Troubleshooting section.
AC POWER SWITCH
Before applying power, check all connections and turn down the gain controls. The "soft start" sequence starts with the POWER indicator
LED at half brightness. A few seconds later the fan starts, the POWER indicator fully illuminates and the amplifier mutes for two seconds.
The CLIP LEDs will glow bright red. When the CLIP LEDs go out, the amplifier is ready.
FRONT PANEL LED INDICATORS
At full brightness, the green POWER LED indicates that the amplifier is operating. Half brightness indicates the
amp is in its start-up sequence or STANDBY mode.
As the input signal strength increases, the green SIGNAL, -20dB, and amber -10dB LED indicators light
respectively at 0.1%, 1% and 10% of full power.
The red CLIP LED indicator flashes during overload (clipping). A bright, steady glow indicates protective muting;
if this occurs during use, see Troubleshooting.
The yellow BRIDGE LED illuminates when the MODE switch is set to BRIDGE.
The blue BI-AMP LED illuminates when the MODE switch is set to BI-AMP.
The orange PARALLEL LED illuminates when the INPUT CONFIGURATION switch is set to PARALLEL.
GAIN CONTROLS
Turn down the gain controls before applying power. The gain controls are detented 21 steps for repeatable adjustment. Surrounding the gain control knob, the attenuation level is shown
in dB. The gain structure may be selected on the PL2A. On the rear panel you will find a switch labeled
GAIN-SENSITIVITY SELECT; you may select from +4 dB input sensitivity, 32 dB
or 26 dB of voltage gain.
Front panel: gain controls and indicator LED’s for
signal level, clip indication, power status indication,
and operating mode (bridge, parallel, bi-amp)
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