A common question asked of Naim is why, where a dedicated power supply is used, are signals routed from the pre-amp through the SUPER-CAP, HI-CAP or FLAT-CAP to the power amp, rather than directly from the pre-amp to the power amp?
The reason is that the absolute earth reference for the system is the reference for the pre-amp, which is the SUPER-CAP, HI-CAP or FLAT-CAP earth. The signal is routed from the pre-amp to the power supply using the same interconnect that takes the power feed from the power supply to the pre-amp. It also connects the two earths together. This minimises differential voltages caused by interfering electric or magnetic fields being generated between the power feed, signal and earth, so maintaining the correct relationship between signal and earth inside the power supply. The power amp is connected to the properly referenced signal at the power supply output.