This would be extreme tinnitus torture

My wife lives with tinnitus. She says it's maddening. 

tinnitus  was Phil`s gift to me at Bill Graham Auditorium 

> "After a few minutes, you’ll already start to hear your own heartbeat. A few minutes after that, you can hear your own bones grinding and blood flowing."

Sounds like what you experience in a sensory deprivation tank. I did one of those back in the early 80s and lasted an hour.

I can't really imagine what that room would feel like. I read about it, but...

There is an anechoic chamber at Sacramento State. I used it a couple of times when I took an acoustics class there.
If I recall, I used it for an assignment to measure frequency wavelengths of various musical notes at different volumes.
I also tried playing an acoustic guitar in there. The room was so dead, there was barely any resonance from the guitar.
I also remember getting a little dizzy if I didn't move around. I used their hat channel wall construction model when I built my home studio.
The room is still there. https://www.csus.edu/college/natural-sciences-mathematics/physics-astron...

Tinnitus truly sucks, but I can always tune my guitar to a perfect "A" note.

I have tinnitus for 40+ years.  Maddening at times:  Loud summer crickets all the time.  Music in the background really helps.