The human auditory system will analyze the time differences between 2 ears within small range of frequency known as critical bands. If the frequency is less than thousand to thousand five hundred Hertz, the interaural time variation is calculated based on the interaural phase difference in the signals received by both ears. The obtained sound is evaluated depending on ear signal analysis. If both ears receive pure tones, then the time dependant phase between 2 ears will perceive sound based on frequency variation between ear signals.
If the frequency variation between ear signals is less than certain hertz, then the auditory system will pursue the changes through tinteraural time variation. Due to this, the auditory events are perceived that moves through your head. The perceived direction will correspond to your immediate interaural variation in time. For higher frequency variation between ear signals, the auditory system will pursue changes with interaural parameters. The diffused auditory event will appear and sound will match up to an overlay of both ear signals that means loudness and amplitude that change rapidly.
For the difference in frequency in the ear signals greater than thirty hertz, you can perceive a difference effect known as cocktail party effect and auditory system will be capable of analyzing the ear signals which are presented through 2 different sources of sound at various locations and you can perceive 2 distinct signals.
You can experience binaural beats without using headphones and they will appear when you play 2 unique pure tones with loud speakers. You will perceive a similar sound and auditory events that pass through the hall at minute differences in frequencies and you will diffuse sound with a higher frequency difference. The frequency difference is apparent and sound sources appear. With higher frequency difference, you can apparently hear localized sound sources. But the effects are higher with headphones when compared to loudspeakers.
Try the binaural beats below: