Today’s power grid cannot be compared to the power grid of a hundred years ago. The advent of switching power supplies, LED lighting, heavy industry and other sources of interference have caused that beautiful 50 Hz sine wave to become quite polluted. Your author wonders how that affects an amplifier. After all: that ‘heavy duty’ power supply just removes all kinds of noise… right?
Measurement is knowledge, right? Yes… in certain cases it it. In this case, it certainly helps to understand the influence of mains noise on playback quality.
In this case, it’s pretty simple: as we increase the noise, we see the noise floor increase. That’s a pretty easy test and hard evidence that contamination on the grid is measureable and yes… audible.
Before we give too much away: check out the video below that we made around this topic. Have fun!