Crest Audio PRO 200 SERIES, Owner'S Manual

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Features Overview 3
Front Panel
1
Rack Mounting Ears
Two front-panel mounting holes are provided on each mounting ear.
2 Input Attenuator
Whenever possible, set the attenuator fully clockwise to maintain opti-
mum system headroom. The input attenuator controls (one for each
channel) are located at the front panel, adjust gain for their respective
channels in all modes. See the specifications at the end of this manual
for standard voltage gain and input sensitivity information.
When operating in the bridged mode, both attenuator must be in the
same position so the speaker load will be equally shared between the
channels.
See — Chapter 4 on Bridged Mono mode operation for more infor-
mation and precautions.
3
ACL (Automatic Clip Limiting) LED
A channel’s ACL LED will light at the onset of clipping. If the LEDs are
flashing quickly and intermittently, the channel is at its clip threshold.A
steady,bright glow means the unit is clip limiting,or reducing gain to pre-
vent severely clipped wave forms from reaching the speakers.During ini-
tial power up,the ACL LED will light to indicate that the Auto Ramp gain
reduction circuitry is activated. This will prevent sudden signal bursts
when the speaker relays are closed.
4 Signal LED
This LED lights when its channel produces an output signal of approxi-
mately 4 Volts RMS or more (>0.1 Volt at the input, with 0 dB attenua-
tion and x40 Voltage gain). The state of this LED is useful in determin-
ing whether a signal is reaching the input and is being amplified. This is
especially true when the unit is operated far from the connected speak-
ers
Front Panel - Pro 8200 shown
1 2 3 4 7 5 6 9 8
Each Pro 200 Series
amplifier channel features
five front panel LED indica-
tors: ACL, Signal,Temp, DC
and Active.These LEDs
inform the user of operat-
ing status and warn of pos-
sibly abnormal conditions.
®