Crest Audio CPX 3800 - Manual (Page 17)

p. 17
features overview
3
indicators
CPX™ Series amplifiers feature three front panel LED indicators per channel:
GCL™, SIGNAL and POWER. These LED indicators inform the user of
each channel’s operating status and warn of possible abnormal conditions.
3 GCL (Gain Comparator Limting) LED
A channel’s GCL LED will light at the onset of clipping. If the LEDs are
flashing quickly and intermittently, the channel is just at the clip threshold.
A steady, bright glow means the amp is clip limiting, or reducing gain to
prevent severely clipped waveforms from reaching the loudspeakers. See
the Gain Comparator Limiting section for more information. During ini-
tial power-up the GCL LED will light to indicate that the AUTORAMP™
gain reduction circuitry is activated. This prevents sudden signal bursts
when the speaker relays are closed.
4 Signal LED
This LED lights when its channel produces an output signal of about 4 volts
RMS or more (0.1 volt or more at the input, with 0 dB attenuation and
standard x40 voltage gain). This signal indicates whether a signal is reaching
and being amplified by the amplifier.
5 Power LED
The Power LED indicates that its channel’s output relay is closed and the
channel is operational. It lights under normal operation and remains on, even
when the channel is in Gain Comparator Limiting or GCL gain reduction.
These protection features leave the output relay closed. If the Power LED goes
off, there is no signal at the output connectors.