How do I operate the Red 5 and how can I detect a fault?

The Red 5 Precision Stereo Power Amplifier possesses 2 x 250W RMS continuous rating into 8ohms and a peak capability of over 800W with extremely low distortion and wide bandwidth. Some tips on operation and fault detection for the Red 5 are provided below.

Operational Tips

The Red 5 power switch is an illuminated push switch on the front panel. Press this to start the
amplifier. It will take a little time before the mains switch LED
cluster lights up (when lit this indicates that the power supply
sections of the amplifier are running correctly and up to full voltage).
After the power supply sections are running the amplifier will then
open for operation (the Operation LED will light to indicate this). This will take
approximately 15 to 20 seconds from pressing the Mains switch .
It is best to wait at least one hour before operation for the best possible
performance of the amplifier and several hours if the amplifier has
been in transit or stored in a cold environment. To switch the amplifier off press the Mains switch again . The
amplifier will revert to Standby mode over a period of a few seconds ,
the LEDs will indicate the status of the amplifier. A Standby LED indicates that the mains power is connected to the IEC mains inlet plug on the rear of the amplifier and that the amplifier is
not switched On .

Fault Detection

The Red 5 has several protection systems which monitor the operation
and performance of the amplifier. The protection systems sense over
current, short circuit, over temperature and unsafe DC conditions.
Should any condition develop which might damage the amplifier, the
protection system will switch the amplifier back to Standby mode. To
reset the amplifier after it has shut down, switch the amplifier off
using the Mains switch, and wait at least one minute before switching on
again. If the fault condition continues the amplifier will shut down
again, without causing damage. The protection systems take into account the short peaks which occur in
music, by allowing short term overloads within the limits of the
circuits. However, if long term overload begins then the systems will
protect the amplifier. Although these protection systems are
comprehensive, all the sensing is done without any components in the
audio path. Dynamically coupled power rails ensure that the power supplies operate
as a truly balanced system, thereby preventing ground loop modulation.
The output stages run in class A/B mode, with a sliding bias arrangement.
All driver stages are pure class A with custom manufactured Mosfets at the outputs.
The output circuits have a very low inductance, allowing the Red 5 to get the best out of "difficult" speakers.

Specifications

Continuous output: 250W RMS into 8 Ohms (THD < 0.05%)
400W RMS into 2 Ohms (THD < 0.05%)

Dynamic Headroom: 300W into 8 Ohms
520W into 4 Ohms, at 1kHz 20 cycles on, 180 cycles off

Peak Pulse Output: 75V pk for 8ms burst, equivalent to 800Wpk into 2 Ohms

Output Z: 0.03 Ohms and 2.6uH

Frequency Response: 1Hz to 39kHz (-1dB)
1Hz to 75kHz (-3dB)

Signal to Noise: Better than -105dB (A weighted at 2/3 full power)

Gain: 33dB

Slew Rate: >70V/uS measured with 1kHz 20Vpk square wave

Channel separation: >95dB un-weighted

Input Sensitivity: 1V for maximum rated output

Input Z Balanced: 100Kohm and 22pF