Dude, I would dump this article and move on. I assure you this article is NOT worth studying in depth.
I can’t think of any way to implement a 1.681% ratio in any area mixing, weather its decibels, subtractive synthesis, wet/dry blends, pan law, attack/release compression times…I’m sorry, I just think this number is completely useless.
If you want to experiment with ratios, I would explore sub-division ratios based on the BPM of songs long before messing with that 1.681 thing. Like, take 2 verbs, set one to 1/4 notes and then blend it with a long verb a 2x whole notes. That’s an 8:1 ratio. Or try combining three compressors with the attacks times doubling but the release gain reduction reducing in half. Or experiment with time delay ratios on a doubler like 8 ms (panned left) 16 ms (panned right) 32 ms (panned left).
There’s just a ton of more meaningful ratio experiments you can do!