White noise is the original sleep sound — the steady, even "shhhhh" you hear when you tune a radio between stations. It's the most studied, most recommended sleep aid in audio form, and the foundation of every good sound library.
What white noise actually is
Technically, white noise is an audio signal with equal energy across the entire frequency spectrum your ear can perceive. Practically, that means it sounds like a soft, hissing waterfall that doesn't seem to come from any single direction. Your brain has nothing to latch onto — no melody, no rhythm, no abrupt changes — so it stops scanning for sounds and lets you settle.
Why it works
Sleep gets disrupted not just by loud sounds but by changes in sound — a creak, a snore, footsteps in the hall, a delivery truck. White noise raises the auditory baseline so those smaller, irregular changes get absorbed into the background. The result: fewer micro-arousals, deeper continuous sleep.
Best for these situations
Volume matters. Pediatric guidelines suggest keeping white noise around 50 dB or below — about the level of a quiet refrigerator — and at least a meter away from a sleeping baby's ear. Loud enough to mask noise, not so loud that it becomes the disruption.
White noise vs pink noise vs brown noise
If white noise feels too sharp or hissy for you, try pink noise (warmer, softer) or brown noise (deeper still — closer to a steady rainfall). Each color has slightly different energy distribution across frequencies, and the right one is mostly a matter of personal preference.
Best pairings in Night Light X
- Pair with a warm amber glow for newborn sleep.
- Combine with rain for a richer, more textured soundscape.
- Use the sleep timer so the noise fades after you're under.