This project is a passive load for power amplifier measurement.
There is not much that can be said about construction of this design. The main part of every passive load is high power resistor.
I used one 50W 6R8 resistor per channel. They are attached to the two radiators that are part of the box. Output measurement signal is taken from the potentiometer that is attached in parallel with load resistor.
The rest of the case is made of PCB laminate and painted black. This device was used to measure my BridgeClone and Dracula amplifiers.
On the picture below there can be seen my attempt to make my own current transformer to isolate power amplifier from computer signal card. This approach could also allow me to direct measure od bridged amplifiers.
It appeared however that results were worse than in previous described concept so I abandoned this idea.