371. Stampede of noisy elephants?

The sound produced by them has been compared to "a stampede of noisy elephants," "a deafening swarm of locusts,""a goat on the way to slaughter"and "a giant hive full of very angry bees. Some Freddie "Saddam" Maake claims to have invented it by adapting an aluminium version from a bicycle horn after removing the black rubber to blow with his mouth. He later found it to be too short and joined a pipe to make it longer.
What am I talking about?