Many years ago, I was under a vehicle mig welding. I didn't have ear plugs in, which is very rare for me. A red hot spatter ball shot in into my ear and landed what appeared to bounce right on and off of my ear drum, unobstructed. I heard it go "bong" off the eardrum membrane.
Seconds later the pain was excruciating. Fortunately, there was no hearing loss that I'm aware of, anyway.
So, Steve, I can appreciate your BIL's dilemma...
'79 CJ5, AMC 360, t-18/d20 twin stick, dana 30/amc20(Mosers), Edelbrock Performer intake, Holley 600, ps/pb, DUI HEI, 'glass tub/1pc. tilt nose, 33x12.50 BFG AT's.
There's a fine line between "hobby" and "mental illness".