"The Loudest Lullaby (You've Ever Heard)" is a Sesame Street song performed by Grundgetta. She sings how the latest lullaby goes against the conventions and is very loud.
Writer Norman Stiles reflected on the song's original intent:
“We wrote this great song, “La la la, la la la, it’s the loudest lullaby you’ve ever heard.” It had sound effects of garbage trucks, traffic and horns. It was loud. Jon Stone, the director, absolutely hated it! He had power at the time to change things that he really felt strongly about. The bit that ended up on the show is nothing like the one I wrote, Grundgetta singing it at nighttime to Oscar in his trashcan, who falls asleep while everyone else on Sesame Street, who had been sleeping, yelling and complaining about all the noise that woke them up. It ended up being Grundgetta alone, on Sesame Street at night, singing for only fifteen to twenty seconds of the lullaby to nobody. It had no purpose and made no sense, but I loved it. It was so the perversity of Oscar that he would fall asleep to this while everybody else was saying, “Keep quiet!”.”
The song ended up also being used in a season 21 episode, where Oscar, Snuffy and Alice listen to a truncated version playing on the radio (as performed by Grundgetta and her back-up band, the Grungettes).