The closer to the ear the microphone is located, the simpler the process becomes.

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The Digital Silence DS-421D headset is also fitted with a Wolfson WM7130 MEMS microphone in each ear bud to pick up the ambient noise around the user prior to cancellation.

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The throat mike removes extra microphone noises while the in-ear speaker bud provides clear, crisp audio.

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Hands-free kits - an earpiece and clip-on microphone - have been marketed as an alternative to holding the mobile close to the ear while making calls.

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Other smart touches include the circumaural ear cups that insulate the listener from noisy urban environments, and an optional cable with a smart remote and microphone for taking and receiving calls and controlling the music on Apple devices.

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