Final testing of the '5 Clip' amplifier board is now complete and ready to order, this variant replaces the original power/amplifier board in the early '5 Clip' style amplifiers.
The board is similar in design to the original '4 Clip' variant but has re-designed processor interconnect, control logic and power supply circuits.
The power supply from the original OEM board has been entirely re-designed to use 'high reliability' industrial grade isolated DC/DC converters rather than the linear regulator method adopted by Harman Becker. This addresses some significant weaknesses with the OEM design, the original linear regulator is inefficient generating unwanted heat and would occasionally fail destroying the flash memories and data bus interfaces on the processor card.
The fan is also dual speed and switched to high/full speed running when the case temperature increases to the threshold determined by the temperature sensor on the processor card.
All control logic for the amplifier wake, fan control, standby and mute control is optically isolated to ensure both reliability and improve sound quality by eliminating ground loops. In the original Harman Becker design, the fan is audible in the speaker channels at low volume, possibly why the fan rarely runs..... but thats just speculation!.
Pictures of the board are shown without the Subwoofer SMPS's and Class-D amplifiers:
