Free tool

The focus sound mixer

Brown noise is a deep, steady sound with more energy in the low frequencies than white noise — closer to rumble than hiss. This free mixer runs in your browser and layers it with soft rain and an optional 40 Hz tone: no app, no account, press play and get to work.

Beat:

Brown noise 55
Rain 40
40 Hz layer 18

The binaural layer sends a slightly different tone to each ear — it only works with headphones, one channel per ear. Keep the volume comfortable. This is a relaxation aid, not a medical device; research on gamma-frequency audio is early and mixed. If you have a seizure disorder or other health concerns, check with a professional first.

How to use it, the ritual way

One sound
Pick a mix and keep it. The point is a steady signal that says "we work now" — not a playlist to fiddle with.
One task
Write a single sentence describing what you'll do before you press play. Not a list. A sentence.
One block
Pair it with the focus timer — 25 or 50 minutes, then a real break.

Prefer crafted tracks?

The 40 Hz Focus Kit

This mixer is a sketch. The kit is the painting — eight composed tracks (piano, harp, violin, rain) over exact-frequency tones. About 5.3 hours, offline, yours forever. Honestly: you don't need it to focus — this mixer stays free either way.

Hear the previews → 30-second listens · €15 once