If you're interested to see what power grid interference looks like, take a look at the videos below, or a comprehensive article about it here: https://rdacoustic.cz/en/blog/2021/04/30/f4sx-audio-power-filter/ (explains in detail what I did here and includes background info + why is it important...
We measured the high frequency noise in the power grid. The voltage going to the measuring kit is conducted by a common EURO cable and the RD Power Filter in order to compare their efficiency. I have made measurements on four different places for comparison.
Read more at...
I'd like to share an interesting article with pictures and animations
https://www.rdacoustic.cz/en/blog/2019/03/30/acoustics-theory-sound-behaviour-in-closed-space/
link
High End speakers Evolution are designed for truthful stereo 2.0 listening. The Evolution speakers are characterized by full details, excellent localization and spaciousness of musical instruments. Evolution speakers contain only one speaker driver with very high sensitivity and unique...