after that , scientists invent many accessories for to him, in particular, the frenchman ernesto mercadier had the idea of ​​​​creating the world's first headphones that connected to the phone . it's the same time. an english company installs microphones in concert halls and invites its subscribers to listen to symphonies through headphones; this makes the invention, revolutionary at that time , popular two decades after the advent of radio, american engineer nathaniel baldwin literally assembles his version of headphones with good quality in the kitchen sound. the americans began to use this invention for military purposes. headphones are beginning to acquire the features of modern technology. device in 1925, with the discovery of the so-called dynamic loudspeaker, the part in which the conversion of an electrical signal into sound takes place, the sound quality becomes cleaner and better, thanks to which headphones begin to be used in recording studios, the first professional model for these purposes is created in germany in 1937 , but still these headphones had a flaw. they transmitted