Crest Audio CPX 3800 Indicators, 3GCL Gain Comparator Limting LED, Signal LED, Power LED

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.

3GCL (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.

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