'Quietest place on Earth' anechoic chamber

It’d be a nice experience. Next up would be the good old sensory deprivation tank.

I’ve been in that very room. I sat inside of it with the lights out for about 30 mins.

Sounds in your body; breathing, pulse, etc are amplified or at least isolated so that you can hear them clearer. It shows you exactly how much reflected sound plays a part in your sensory experience and placement/equilibrium. When you are talking to someone next to you it feels like they are 30 feet away.

While it’s reasonably unnerving, it doesn’t exactly take you to the upside down.

I don’t doubt that it may be the quietest anechoic chamber on earth. There are many of them in the world; Apple HQ has one, and I imagine most major appliance manufacturers, etc. do. Not all of them have applied to the Guinness Book to be measured.

Definitely one of the coolest places I’ve been to!

Must be the deadest place on Earth.

This could be the loudest quietest place on earth 

https://www.blackbirdstudio.com/studio-c/

Those are ATC 300 speakers - 121 dB spl continuously with 0.3% THD.

I'm not sure that dead a room would sound good for reproduced sound. I know we deal with all kinds of issues involving reflections, room modes, etc. but overdamped rooms sound and feel claustrophobic to me.