The headset consists of two headphones, one for each ear (if the stereo headphones, a headset is to the right ear, the other to the left ear, the earpiece for the ear right is often marked with the letter "R" (for "right" word for "right" in English) or a sign in red, the earpiece for left ear is often marked with the letter "L "(for" left ", a word meaning" left "in English) or a blue sign). Each earpiece contains a mini-chamber consists of a small speaker with a membrane, very thin, can reproduce all audible frequencies, or at least a part, as the value of bandwidth of the speaker. The helmets can be used with audio equipment room, a stereo, CD player or computer, and with mobile devices (digital music player, cell phone, etc.)..

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