It's a raw nearly minute-long recording of an electric fan running. Sounds similiar to a little aeroplane motor mid-air. Recorded using a zoom h2. Originally 96khz/24-bit wav. Converted to flac using audacity.
This is a recording of a kitchen fan. One attached to the bottom of a microwave, vented, and above the stove top. On the fastest setting. Recorded with a rode nt1 and avid omni mic-pre.