How should the earphone be positioned for best intelligibility?

• A. Put the earpiece around the ear with a loose seal
• B. Wear the earpiece around the neck
• C. Clip the earpiece to the cap
• D. Place the earpiece over or in the ear with a comfortable seal and minimal external noise leakage

Answer: (D)

Clear intelligibility comes from delivering the sound directly to the ear with a comfortable, tight seal to minimize ambient noise leaking into the ear. When the earpiece sits over or in the ear with a snug seal, the signal-to-noise ratio is maximized, so the spoken voice is heard clearly and details aren’t masked by surrounding sounds.

Wearing the earpiece around the neck or clipped to the cap fails to provide a direct, sealed path to the ear, so more environmental noise can creep in and the signal is harder to understand. A loose seal around the ear also allows more external noise to leak in and distorts the received audio. Thus, placing the earpiece over or in the ear with a comfortable seal and minimal leakage gives the best intelligibility.