A question: If you didnt use headphones, then how is it possible that the bineural beats work? Correct me if I'm wrong, but as I know the point with bin. beats is that they are slightly different in each ear so that the brain gets a specific message?

Wikipedia:

The brain produces a phenomenon resulting in low-frequency pulsations in the amplitude and sound localization of a perceived sound when two tones at slightly different frequencies are presented separately, one to each of a subject's ears, using stereo headphones. A beating tone will be perceived, as if the two tones mixed naturally, out of the brain. The frequencies of the tones must be below 1,000 hertz for the beating to be noticeable.The difference between the two frequencies must be small (less than or equal to 30 Hz) for the effect to occur; otherwise, the two tones will be heard separately and no beat will be perceived.