SoundMasker
Press play to start the sound
Binaural 2 Hz A soft start: brown noise, rain, a forest brook, and a few birds. Save it to keep your own version.

Brown noise 22

EqualizerLow to high

Binaural 2 Hz 62

A binaural beat in the delta range, about 2 hertz. It only works over headphones, with a slightly different tone in each ear.