Getting a good night’s sleep is hard. A third of all American adults report getting less than the daily recommended amount of sleep nearly every night. Too little noise, and the mind starts to race.

“The sound machine can generate any of several types of sound, from nature [or] music,” Dr. Cory Portnuff, an audiologist at the University of Colorado Health’s Hearing and Balance Clinic, says. In ...

Thankfully, sound machines are simple devices. Most look like fancy alarm clocks with a few more dials and buttons and switches to access their various sounds and features. If you’re ready to upgrade ...