A binaural beat is not a sound that exists anywhere in the room — it is an effect your own brain constructs. Send a slightly different pure tone to each ear over stereo headphones, and rather than hearing two separate pitches, most listeners perceive a single, rhythmic pulsing tone equal to the difference between the two — the "beat." This page's player is preloaded with a 200 Hz carrier and a 10 Hz beat (the alpha band), ready to start the moment you press play on the Binaural tab below.
The beat rate is grouped into the same five bands used in EEG research: delta (0.5–4 Hz) for deep sleep and rest, theta (4–8 Hz) for meditation and creativity, alpha (8–14 Hz) for relaxed focus, beta (14–30 Hz) for concentration and alertness, and gamma (30–100 Hz) for peak cognition. Each band is traditionally associated with a different mental state, and picking a preset here sets both the beat rate and a suitable carrier tone in one step — 100–200 Hz carriers sit low and unobtrusive, while 432 Hz offers an alternative tuning some listeners prefer for longer sessions.
Binaural beats only work over real stereo headphones or earbuds — speakers mix both channels together in the room before they reach your ears, which erases the separation the effect depends on. If you need something that works through regular speakers too, the isochronic tones generator produces a comparable rhythmic pulse using a different technique that does not require stereo separation.
Research on binaural beats and brainwave entrainment is still limited and mixed: some studies report small effects on relaxation, anxiety, or focus, while others find no measurable difference from a matched control sound. It is not an established medical treatment, and no health claim is made here — many listeners simply find a steady, predictable tone useful as a backdrop for meditation, work, or winding down before sleep, independent of the entrainment claim.