A headset is a headphone combined with a microphone. Headsets provide the equivalent functionality of a telephone handset with hands-free operation. Among applications for headsets, besides telephone use, are aviation, theatre or television studio intercom systems, and console or PC gaming. Headsets are made with either a single-earpiece (mono) or a double-earpiece (mono to both ears or stereo). The microphone arm of headsets is either an external microphone type where the microphone is held in front of the user's mouth, or a voicetube type where the microphone is housed in the earpiece and speech reaches it by means of a hollow tube.
Earbud-style headphones range from the disposable models you get on a plane to the ones that are included with your smartphone to high-performance buds that offer sonics rivaling full-size models. Their tiny earpieces rest on the outer ear or need to be inserted into the ear canal, and some models, particularly sport buds, include wings or fins for a more tailored, secure fit.
While noise-canceling headphones are what it’s best known for, Bose makes plenty of other high-quality headphones and earbuds for people who don’t want or need noise cancellation, which degrades audio quality and costs a premium. From true wireless AirPod competitors to old-school wired earbuds, to just cheaper wireless over-ear cans, Bose makes a headphone for every style and, more importantly, for every budget.
Electrostatic drivers consist of a thin, electrically charged diaphragm, typically a coated PET film membrane, suspended between two perforated metal plates (electrodes). The electrical sound signal is applied to the electrodes creating an electrical field; depending on the polarity of this field, the diaphragm is drawn towards one of the plates. Air is forced through the perforations; combined with a continuously changing electrical signal driving the membrane, a sound wave is generated. Electrostatic headphones are usually more expensive than moving-coil ones, and are comparatively uncommon. In addition, a special amplifier is required to amplify the signal to deflect the membrane, which often requires electrical potentials in the range of 100 to 1000 volts.