Browser audio / Two channels
Binaural Lab
Set a carrier and a beat gap. The browser sends one steady sine tone to each ear.
Headphones required. Start low. Stop if the sound feels uncomfortable. Do not use this while driving.
How it works
The left channel plays the carrier. The right channel adds the selected beat gap. The channels stay separate, so headphones matter.
A 1983 U.S. Army memo, later released through the CIA Reading Room, assessed the Monroe Institute's Gateway training and described difference-tone audio. That strange history is the inspiration here.
This is a simple two-tone experiment, not Hemi-Sync, Monroe Sound Science, or a medical device. It makes no medical or mental-state claims and has no affiliation with the U.S. government or Monroe Institute.
The historical references are the 1983 Gateway Process memo and the Monroe Institute sound history.