How to choose sound machines

Yes, when used correctly, but volume and distance are the whole game. A 2014 American Academy of Pediatrics-cited study found many infant sound machines can exceed safe noise limits at close range, so pediatric audiologists advise placing the machine at least about 7 feet (200 cm) from the crib, keeping it well below maximum volume, and not running it at high levels all night. As a rule of thumb, if it's loud enough to interrupt a normal conversation in the room, turn it down.

Across the room from the crib — never inside it, mounted to a rail, or right beside baby's head. Per AAP safe-sleep guidance the crib should stay bare and free of cords, so route any power cord along the wall and well out of reach to avoid a strangulation hazard. A dresser or shelf several feet away gives gentle, even sound without the hearing risk of close placement.

For masking household sounds, a steady broadband noise works best: white noise is even across all frequencies, while pink noise is softer and deeper, which many parents find less harsh. Heartbeat and womb sounds can soothe newborns in the early weeks but are usually too quiet to mask a doorbell or a sibling. Pick one continuous track and keep it consistent so it becomes a reliable sleep cue.

It's fine to run it through naps and overnight as long as the volume is low and the unit is across the room — continuous play actually helps, since it also masks noises that could cause a wake-up. The caution is loudness, not duration. Keep it at a soft, steady level rather than turning it up to drown everything out.