Here’s a knocking indeed! If a man were porter of Hell Gate … freesound audio sample : knock.wav by someonesilly

Here’s a knocking indeed! If a man were porter of Hell Gate,
he should have old turning the key. [Knock] Knock, knock,
knock! Who’s there, i’ th’ name of Belzebub? … [Knock] Knock,
knock! Who’s there, in th’ other devil’s name?

Macbeth Act 2, scene 3, 1–8