Instead of arguing without end about what most cannot verify nor understand completely anyway i proposed in my post above a simple experiment...😊
Nobody payed attention...😊
Most people prefer to buy something as a new cable for example especially a costlier one as programmed consumers they prefer purchase than making experiments. I know that...
Now this is my post above :
«Simple evidence for that :
put a piece of shungite on the cable connector ends: compression of the signals ...
put a quartz piece on the ends of the same cables connector : decompression of the signals ...
now combine them and hear the result : a balance with improvement in many case... It depend of the cable quality and design ...
No cables designer working with " basic established science/engineering principles in cable/wire electronics" will do that...
By the way i designed my own devices as a shield against EMI and minerals filters : "golden plate" ( shungite+a copper external face + quartz at some point for a better acoustic balance)
I dont buy tweaks...😁 I prefer homemade...»
Now think a second about what i said about shungite and quartz...
Think...
And read that :
"Quartz is an excellent electric insulating material and presents the following electrical properties: electrical resistivity (350°): 7×107 ohm x cm. dielectric constant (20°C – 1MHz): 3,76."
"Despite the poorly ordered structure, shungite has a relatively high electrical conductivity [50,51]. The resistivity of shungite-1 is about 1 Ω cm, whereas the resistivity of shungite-3 is about 10 Ω cm [50]."
«Another carbonaceous filler used in the present work was shungite. Shungite is a mineral that has recently increased in popularity. Shungite is a microheterogeneous natural mineral complex containing non-crystalline carbon, silicates, a small quantity of metal oxides, and organic additives [31,32]. Originally, shungite was described thanks to the resources obtained near the village of Shunga (Russia). Shungite rocks are classified into five types depending on the carbon content. Some deposits consist of almost pure carbon (up to 98% by weight, so-called type I). The most popular variant of shungite is type III (with a carbon content of 20–35 wt.%) [33,34]. Shungite may differ in structure and properties, depending on the place of origin. Shungite is a hard mineral with a compact structure and black color. Its density, depending on the variety, ranges between 2.04 and 2.25 g/cm3. Due to the fact that shungite contains nanotubes and fullerenes in its structure, this mineral is highly porous. Shungite also exhibits conductive properties and considerable mechanical strength [35,36,37]. Its modulus of elasticity is the highest among all of the carbon materials, including graphite. Taking into account the reactivity of shungite, it can be observed that it is more reactive than coke and, at the same time, more resistant to the oxidation process than graphite»
Antonets, I.V.; Golubev, Y.A.; Shcheglov, V.I.; Sun, S. Electromagnetic shielding effectiveness of lightweight and flexible ultrathin shungite plates. Curr. Appl. Phys. 2021, 29, 97–106