Audio headset

Headsets connect over a telephone or to a computer, allowing the user to speak and listen while keeping both hands free. They are commonly used in customer service and technical support centers, where employees can converse with customers while typing information into a computer. Also common among computer gamers are headsets, which will let them talk with each other and hear others, as well as use their keyboards and mice to play the game. Telephone headsets generally use loudspeakers with a narrower frequency range than those also used for entertainment. Stereo computer headsets, on the other hand, use 32-ohm speakers with a broader frequency range. Headsets are available in single-earpiece and double-earpiece designs. Double-earpiece headsets may support stereo sound or use the same monaural audio channel for both ears. Single-earpiece headsets free up one ear, allowing better awareness of surroundings. Telephone headsets are monaural, even for double-earpiece designs, because telephone offers only single-channel input and output. The microphone arm of headsets may carry an external microphone or be of the voice tube type. External microphone designs have the microphone housed in the front end of the microphone arm. Voicetube designs are also called internal microphone design, and have the microphone housed near the earpiece, with a tube carrying sound to the microphone. Most external microphone designs are of either omnidirectional or noise-canceling type. Noise-canceling microphone headsets use a bi-directional microphone as elements. A bi-directional microphone's receptive field has two angles only. Its receptive field is limited to only the front and the direct opposite back of the microphone. This creates an "8" shape field, and this design is the best method for picking up sound only from a close proximity of the user, while not picking up most surrounding noises. Omni-directional microphones pick up the complete 360-degree field, which may include much extraneous noise.