You will never encounter sub 20 dBA in your life. Even at night in a very quiet area you'll reach 24 dBA maybe. At that point it is so quiet it becomes weird because you hear the blood flowing in your ears / notice minor tinnitus you have. I have had GPU engineers from TW here, who wanted to learn more about my noise testing, who said "it is scary quiet"
"Threshold of hearing" might work for high, clearly frequency-separated tones, but is completely useless for fan noise and similar
Thanks for that Input and reality check. I often feel some People really don't know what / how DB actually works or what they think is loud …. yes, 1 DB more can be a massive difference, but it's also relative depending on where you start and which frequencies you look at. But especially with our gaming rigs and stuff it's a mood Point to go below a certain threshold. A) it won't even be noticable below the table or more than 1m away from your ears. B) nearly no one games with an open bench - so there is a case around it which further reduces the noice. C) even our Keyboard and mouse are louder than that and Closer to us
(and there we don't even go into "and then they Play with expensive headphones or Speaker Systems turned up to max after spending 1k € to get their pc one more db down "
)
I helped a friend build his "super duper Cinema and Meditation room" …. he sound-proofed it beyond means (specially 3D-printed tiles similar to how the Sound-Reflectors in the Hamburg Opera-House work, just with Sound-Dampening materials) and had to remove a lot of it again. It gave you bad vibes as it was literally too silent (it was between 5 and 10DB baseline) in there and if you sat on the Meditation mat even with your relaxed / calm heartbeat it felt like the niagarafall would go through your Body - your bloodstream and heartbeat felt that loud (and we're just nod made to be in SUCH quiet Areas
).
Trying to get stuff "too silent" is just making Things worse in some cases
Maybe they want to try out the anechoic chamber (-20DB) once, I mean it's only 99$ or so to see how loud silent can be ^^.