Slo: Sleep Sounds, Brown Noise

Slo is a brown noise and sleep sounds app for iPhone, iPad, and Mac, with 150+ curated sounds for sleep, focus, and relaxation. Play deep brown noise on its own, or mix it with rain, waves, and fan sounds — each layer with its own volume — and set a sleep timer that stops playback automatically.

KEY FEATURES
• Brown noise – deep, low-frequency rumble many people choose for focus and sleep
• White, pink & green noise – broadband noise colors for masking background sound
• Binaural beats & frequencies – binaural beats, solfeggio tones (396–963 Hz, including 432 Hz and 528 Hz) and Schumann resonance tones
• Rain sounds – steady rainfall and distant thunderstorms
• Waves & water – ocean waves, river, waterfall
• Fan sounds – ceiling fan, table fan, airplane cabin
• Nature & ambience – forest, birds, wind, fireplace, campfire, train
• Sound mixing – layer sounds, each with its own volume control
• Sleep timer – playback stops on its own after you drift off

MADE FOR
• Light sleepers who use steady sound to mask traffic, neighbors, or a snoring partner
• Students and deep workers who keep brown noise or fan noise running for hours
• People who wind down to binaural beats, solfeggio tones, or steady frequencies
• People who use sound masking at night to make tinnitus ringing less noticeable
• Anyone building a consistent wind-down routine — same mix, same timer, every night

WHY SLO?
A focused sound machine, not a content platform: 150+ curated sounds, a mixer with per-layer volume, and a sleep timer. No voices, no playlists — steady sound that sits in the background while you sleep, study, or work.

Slo is free to download and try; the full sound library is a premium purchase inside the app.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Terms of Service: https://meltedbutter.co/terms/noise.html
Privacy Policy: https://meltedbutter.co/privacy/noise.html

FREQUENTLY ASKED QUESTIONS

What is the best app for brown noise?
Slo is built around brown noise: play it on its own, or layer it under rain or a fan sound with a separate volume for each layer, and set a timer so it stops on its own.

Does brown noise help you sleep?
Brown noise doesn't treat anything — what it does is mask. A steady low-frequency sound covers unpredictable noise like traffic, doors, and snoring, which is why many light sleepers keep it running at night.

Can I use Slo for tinnitus?
Steady broadband sounds like brown and pink noise can help mask tinnitus ringing — many people set a low volume that makes the ringing less noticeable at night. Slo is a sound player, not a treatment; persistent or one-sided tinnitus needs a medical assessment.

What are solfeggio frequencies and binaural beats?
Slo includes solfeggio tones (396–963 Hz, with 432 Hz and 528 Hz), Schumann resonance tones, and binaural beats — steady tones many people play for meditation and winding down. Try one with headphones and keep it if you like it.

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