The working principle and application of wired headset

How it works: Headphones are a pair of conversion units that accept electrical signals from a media player or receiver and convert them into audible sound waves through speakers close to the ear, generally separate from the media player.Promotional & Disposable Wired Earphones， Plug connection.

Headphone applications: Headphones are mainly used in mobile phones, walkmans, radios, portable video games and digital audio players.

The advantage is that you can listen to the sound alone without disturbing others; it can also isolate the sound of the surrounding environment, which is very helpful for those who use it in noisy environments such as studios, DJs, travel, sports, etc.

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Where are disposable earphones generally used?

There is no sound on one side of the earphone, why?

Are disposable earphones provided on the plane?