Cleaned the HTML so it is readable:
My first modification was installing a second PSU into my Hypex Nilai DIY500 Stereo amp to double the power output into 4 ohms. I disassembled the amp, drilled 14 new PSU mounting holes and five large holes to fit some metal Temu air vents. The additional PSU is supplied with two amplifier connection cables (not required), a power input cable and a 12-pin auxiliaries cable (J5).
I soldered the power input cable to daisy chain it with the original power input cable.
I also soldered five wires on the 12-pin auxiliaries cable to the original 12-pin cable. This required carefully removing some of the insulation from the original cable, soldering the ends of the new cable onto the original, and then insulating with electrical tape. The five wires I connected were:
- Pin 2: Ground
- Pin 7: Pushbutton+
- Pin 8: Pushbutton-
- Pin 9: Trigger+/-
- Pin 10: Trigger+/-
The end result sounds slightly better than with a single PSU, in my opinion. The extra headroom seems to have given the bass more weight behind it and added to the overall clarity at louder volume. Nilai with two PSUs. Case underside.
My second modification was adding a gain switch (on-off-on 6-pin) to the rear panel. It seems to work and can be easily reversed if it has any negative effect on the sound.
