This is the short answer: 240 decibels is what it takes to explode someones head.
EXPLAINATION:
Decibels is the measurement of sound. If you know what frequency is, then good. You’re gunna have to. If you’ve used a dog whistle you know that the sound that is making the dog freak out is too high of a frequency for the human ear to handle, therfore you not being able to hear it. Infrasounds are sounds that you can’t hear due to the high or low frequency. 125+ decibals can cause perminent or long-term hearing damage. Now, if you don’t know an ipod at max volume is 115 deciables (5 more than a chainsaw). Now let me introduce you to LRAD Long Range Acustic Device. This thing can get so loud it can go to 166 dB without breaking a sweat, which is 4 away from sound itself make you breathe faster. One of LRAD’s selling points is that you could mount it to a helicopter and go into the air blasting music so people more than 2 miles away would cringe. Time to get to the point. Infrasounds can make your body vibrate and do things you wouldn’t think sound was capable of. Objects can only stand so much force of expansion, before it pops. This includes liquid filled organs, such as the head. Sense the head is so insolated it would take 240 decibles to explode someones head, which obviously would kill them. It could take less, so if I were you I would take percausions. Here is a link to a Game Theory episode which goes in depth of sound: Game Theory: Is Mortal Kombat's Killer Scream Possible? - YouTube