today in pedantry born of extreme annoyance and doesn't-anybody-go-to-school-anymore grumpiness:
the term "sound barrier" has absolutely nothing to do with how loud something is.
a powerful singer does not break the sound barrier. a loud crowd does not break the sound barrier. if you hear an opera soprano belt out an aria and you say she broke the sound barrier you sound like a fucking idiot. that is not what it means.
"but it's just a joke why should i car--"
no. sit down. THAT IS NOT WHAT IT MEANS.
"sound barrier" refers to the increase in aerodynamic drag that occurs as a moving object approaches the speed of sound.
it's called a "barrier" because when the first aircraft starting reaching high enough speeds, they would shake so much pilots were afraid they would get torn apart. it was perceived as a real physical limit, but that perception was false. there is no actual barrier. there is only engineering; it was the drag on the aircraft making them feel like they were shaking apart. turns out if planes are built well enough and go fast enough, they can break the sound barrier just fine without falling apart. the first time this happened was in 1947, in a plane flown by US Air Force pilot Chuck Yaeger.
this means that "breaking the sound barrier" applies to things that are moving very fast, not to things that are very loud.
please read that sentence again to make sure it sinks in. fast, not loud. read it again because tiktok has been lying to you and you need to unlearn what you have learned.
(that also means it applies only where there is a speed of sound, which is not everywhere in the universe. but let's not complicate things by thinking about a pure vacuums or the extreme low density of space.)
the speed of sound varies depending on the density of what it's moving through, but at sea level on Earth it's about 770 miles per hour. once an object is going faster than the speed of sound, it is supersonic--and, again, that refers to speed, not volume. bullets break the sound barrier even if they are muffled at firing. a bullwhip can be snapped fast enough that the very end breaks the sound barrier, even if the noise they make is a sharp crack and not unusually loud.
but people standing still and shouting or singing do not, because nothing that is standing still can break the sound barrier. so unless you are sharing a cool vid of a soprano getting yeeted out of an operatic cannon at >770 mph, she has not broken the sound barrier. and if that is what you are sharing, she breaks the sound barrier whether or not she's singing her aria.
there can be a very loud noise associated with objects moving so fast they have broken the sound barrier. that noise is called a sonic boom, and it happens because the object is generating shock waves as it travels. it's not a single boom; it only sounds like that because when you hear it you are listening at a single point. it is in fact a continuous, traveling shock wave that happens as long as the object is moving faster than the speed of sound. it's just that you only hear it when the shock wave passes directly over you, so it sounds like a finite noise. it's also not necessarily a boom. it can be a crack or a snap or a clap or whatever. it's just called a sonic boom because the ones generated by supersonic aircraft are big fucking booms.
in conclusion please stop saying loud noises break the sound barrier.
🚫 wrong kind of hyperbole: "wow that man shouted loud enough to break the sound barrier!"
✔ right kind of hyperbole: "wow that man ran fast enough to break the sound barrier!"