The highest amount of voltage/amps you can have is anything lower than 20,000. This is good for a subwoofer and it won't kill you. What kills a person is the electromagnetism that occurs when there is an intense surge of electric flow through a medium.
If you choose to destroy your hearing, go ahead and CRANK UP THE NOISE, but latter in life you'll pay for your stupidity. I know, because I now suffer from tinnitis (ringing in ears) from continued exposure to loud noises, and it drives me nuts! but as Forest Gump would say," Stupid is as Stupid does ".