I don’t think it has to be that precise, it just needs to be two tones with a slight frequency difference so you get interference coming and going to make a bea

I don’t think it has to be that precise, it just needs to be two tones with a slight frequency difference so you get interference coming and going to make a beat frequency. But i guess your brain does this “in software” since the sound doesn’t actually physically mix in the stereo headphones. I guess if the two tracks are not perfectly synced you just get some phase shift/drift If you search for `binaural` on Spotify or whatever, you’ll find a bunch of playlists. The delta/sleep tracks are probably the easiest to notice the beat since the beat frequency is set to 3-4Hz