You can choose from a range of sounds: rain, stream, ocean, balanced noise, bright noise, and dark noise. View Entire Post › ...

Once you’ve done this, you can quickly turn on the background sound of your choice. Here’s how: Click the Control Center icon in the Mac ... and three more basic white noise sounds—balanced ...

(For this article, I used an iPhone 11 running iOS 15.4.1.) On the main Background Sounds menu page, you can also adjust the volume of the white noise independently from other phone functions.

A great white noise machine drowns out distracting background noise ... at the same intensity. With no variation entering your ears, your brain interprets the sound like a steady hiss.