I almost commented on the reddit post at the time, but decided not to. Now that I see it repeated, I want to. This is a reading comprehension error, I think.

I almost commented on the reddit post at the time, but decided not to. Now that I see it repeated, I want to. This is a reading comprehension error, I think. I guess I'm not 100% sure. That "melting concrete and setting grass aflame" comes from the link, here: http://www.makeitlouder.com/Decibel%20Level%20Chart.txt http://www.makeitlouder.com/Decibel%20Level%20Chart.txt That link has many decibel levels, and examples, and factoids about the things producing the sound, unrelated to the sound itself. I think the chart intends to say that the rocket melts concrete, sets grass on fire 1 mile away, and produces sound that is 220 decibels. Not that the sound itself is melting concrete or setting grass on fire. The reddit post mentions "At 2 kilometers (140+ db), ..." 2km is a little more than 1 mile. So if the sound alone could set grass aflame a mile away, then that would mean that 140db at distance zero is enough set grass on fire. If it can set grass on fire, then it can set a lot of other things on fire. Paper, clothing, hair, etc... Some extremely loud rock concerts hit 150db. So, while I guess I'm not 100% sure that this is an error, I just doubt that rock concert speakers can/would output enough volume to set things right next to them on fire. There would be huge safety issues, and risk of the speakers destroying themselves and other equipment. I know nobody is right next to speakers this loud, but still... I doubt the accuracy of this 'melting concrete and setting grass aflame via sound' factoid. I would love to be shown wrong, because it is really interesting if it's true.