Two tones. One listening experience.

When slightly different tones are delivered separately to each ear, some listeners perceive a rhythmic beat at the difference between them.

For example, a 200 Hz tone in one ear and a 210 Hz tone in the other can create the perception of a 10 Hz beat. This does not mean a physical 10 Hz sound is being played.

Researchers are studying how this listening experience relates to attention and relaxation. Findings vary. A perceived beat does not establish that your brainwaves have synchronized to it.