About this app
Overview, features and application details
Built around deep brown noise, with 150+ curated sounds including rain, waves, fan hums, binaural beats and solfeggio tones. Layer anything over anything with per-sound volume.
Slo is for people who've tried white noise and found it too harsh. Brown noise is the star here: a deep, low rumble that sits further back in your head than the hiss of white noise.
Beyond that there's a big library — 150+ sounds including rain, thunderstorms, ocean, fans, binaural beats and solfeggio tones from 396 to 963 Hz. Everything layers, and each layer gets its own volume slider.
Light sleepers use it to mask traffic, neighbors or a snoring partner. Students keep brown or fan noise running for hours of deep work.
The full library is a premium purchase in-app. What you're paying for is range: if one sound doesn't work for you, there are 149 more to try.
