Operating Your Amplifier: Front Panel Controls And Indicators - MC2 Audio E475 Operating Instructions Manual

E Series – E475 Operating Instructions
Page 13

Operating Your Amplifier: Front Panel Controls and Indicators

1
6 2
5
3
1: Power Switch: This single pole switch turns the amplifier fully off (but does NOT isolate it
from the mains supply).
2: Power LED: This indicates when the amplifier is active. This does NOT indicate the
presence of a mains supply when the power switch is OFF.
3: Signal Meters: These LED bar graphs show instantaneous level on each channel to
indicate proximity to the limiter threshold. Note that if the PRC system is in operation on
either channel, this will affect the readout shown on the respective meter.
The red LED in the meter (Limit indicator) will illuminate when the limiter threshold has been
reached and limiting is occurring. The output current monitor may activate to limit the output
current of the amplifier channel - this can occur even if the amplifier has not reached clipping
point.
The Limit indicator can operate independently of the bar graph meter. Typical conditions that
may trigger the output current monitor circuitry would be very low load impedance, or high
subsonic or VHF levels.
4: Attenuation Controls: These are analogue controls allowing precise level settings. Note
that when channels are linked using the rear panel link switches, some controls may be
inactive - see page NN for details.
5: PRC LED: This illuminates if the Power Reduction Control has been enabled on the
respective channel pair, either manually via the switches on the rear panel or automatically
via the impedance sensing circuit. See page NN for details of switch settings.
6: A/P (Auto Protect) LED: If a condition exists, either internally or externally, that could
cause damage to either the amplifier or the speakers, the protection circuit will disengage the
outputs and the A/P LED will illuminate. The amplifier will continue to be monitored and
depending on the type of fault, will either reset after the fault has cleared, or require manual
resetting by switching off at the mains switch and then on again after a few seconds.