Night wind for sleep, never the same gust twice.

Why it works

Wind heard from inside a house is a narrow band of sound that swells and settles. This page makes it from pink noise through a filter at 400 Hz, with the level moved by two slow cycles whose periods never coincide. It is shaped noise, not a field recording, so it has no birds, no traffic and no loop.

A sound that moves is easier to stay with than one that does not, and it is still weather, with nothing in it to think about. The voice is something to think about, lightly. It tells you how the story ends before it begins, so there is no reason to stay awake for it.

What you are hearing

• Night wind. Pink noise through a narrow band at 400 Hz, rising and falling slowly on a pattern that never repeats. Shaped after wind heard from indoors; it is not a recording.
• The voice. The first four minutes of Aristotle, the Greatest Philosopher, a Lullable story, in a synthesised voice. It only plays if you bring it in.
• The ending. The preview lasts four minutes. Its last ten seconds are a straight fade to silence, so it never stops abruptly.

For a real recording that runs forty minutes, the Lullable iPhone app has rain, waves, a campfire and plain noise, with no voice and no music.