DJ sirens are a staple of club and party culture, where a loud alarm-style sound is used to grab attention and raise energy before a drop. Online, the same effect moved into short-form videos, streams, and memes, where creators use it as a quick signal that something exciting or absurd is coming. Its appeal is simple and reusable: it needs no lyrics, works across languages, and instantly creates anticipation. Like the MLG air horn, it has become a familiar hype cue that viewers recognise immediately, which is why editors keep reaching for it.