4 Hz binaural beats
On the border between theta and delta — slow enough to settle into, not so slow that you sink past the point where a twenty-minute nap still works.
4 Hz is where theta meets delta. It is the rate most nap presets use, including this site's, because the aim of a short nap is to rest without dropping into the deep sleep that produces grogginess on waking. Whether the beat influences that is unproven — the twenty-minute timer certainly does.
The nap logic
A nap of about twenty minutes leaves most people refreshed; one of forty to sixty often ends mid-deep-sleep and produces sleep inertia — the heavy, worse-than-before feeling. That is the actual mechanism behind “power nap” advice, and it is about duration, not frequency. This page pairs a slow beat with the timer that does the work.
- Set the timer to 20 minutes and lie down; do not aim to sleep, aim to rest.
- Keep the volume low — a nap sound you can hear clearly will keep you at the surface.
- The fade-out at the end is the wake-up. Get up on it rather than lying there.
- If you regularly nap for an hour and wake up worse, that duration is the reason.
4 Hz for sitting practice
Outside of naps, 4 Hz is used for longer meditation where 6 Hz feels too present. It is noticeably slower to the ear: the swell arrives about four times a second, which most people describe as breathing-paced rather than pulsing. The third preset pairs it with the 136.1 Hz carrier the meditation page explains.
Neighbours worth trying
Questions
Is 4 Hz good for napping?
It is the conventional nap setting and it is what this site uses. The evidence for the beat itself is weak; the twenty-minute limit is the part that reliably matters.
What is the difference between 4 Hz and 6 Hz?
4 Hz is slower and less present — closer to a swell than a pulse. 6 Hz is the usual sitting meditation rate and slightly easier to follow deliberately.
Can I nap without headphones?
Not with a binaural beat. Use the pink noise generator from a speaker, or isochronic tones.
Why does the sound fade instead of stopping?
A hard stop is a jolt if you are half asleep. Every timer on this site fades over the last eight seconds.
Running this on a phone? The Brainwave Generator app keeps playing with the screen off, works without a connection, and carries the same engine. Free on iOS and Android.