What is the name of the siren sound during the Kill Bill movies?

Question

It happens whenever Beatriz sees one of her former killers.

Answer 1

...,it was the introduction/opening to the theme song to a late '60's/early '70's police drama TV series, called "Ironside", starring Raymond Burr.

...once again, as with all his films, director Quentin Tarantino is guilty of pulling little quips and snippets of obscure '60's & '70's pop kitch, and putting them into his films...

...but then, that's why his films are so interesting and great, if at the very least, on a nostalgic level!!!

Answer 2

"Ironside" by Quincy Jones