Stereophonic headphones - two telephones with a headband, designed for connection to household electronic devices [1]. Headphones are a pair of small-sized headphones or a headset [2] that can be worn over the head or inserted directly into the ear canals. Headphones are often used in everyday life and in professional activities for speech communication and listening to music and speech, when mobility or sound insulation from the surrounding space is needed. Headphones with a microphone attached to them form a headset. Sometimes in professional activity, instead of a pair, one separate earphone is used, it is called a monitor. The name telephone (from ancient Greek τῆλε - far and φωνή - voice, sound) was first used by Philip Reis in 1861 ...