Between white and brown
Pink noise for sleep
Pink noise is 1/f. Rain, wind, and ocean sit here. Lab bursts timed to slow waves are not the same as an 8-hour YouTube video.
The spectrum
Energy falls as frequency rises. It sounds softer than white, closer to weather. Sleep Foundation lists rain, waterfall, wind, river, and ocean as everyday pink.
The lab result people quote
Ngo and others showed that quiet pink bursts timed to slow oscillations can deepen N3 in the lab. That is closed-loop stimulation, not a fan app. Home devices that claim the same result are usually just playing continuous pink.
The 2026 caveat
Continuous pink around 50 dB across a full night has been associated with less REM in recent lab work. If you use pink for sleep onset, a one- or two-hour fade is more conservative than eight hours at conversation level.
By JTT · byjtt.com · hello@byjtt.com