insert earphone
7.19 insert earphone. An earphone coupled by a tube and/or ear mold with the output tip inside the ear canal.
hearing assistance devices/systems (HADS)
7.18 hearing assistance devices/systems (HADS). A group of instruments intended to facilitate hearing by providing amplification of an acoustic signal and/or improving the signal-to-noise ratio by means of a non-acoustic signal transmission method. HADS include personal assistive listening devices, hearing assistance technologies, auditory trainers, large-area assistive listening systems, telephone amplifiers, alerting devices, and other similar devices and may be hardwired or wireless. Annotation See ANSI/ASA S3.47.
hearing aid
7.17 hearing aid. Any wearable sound amplification device designed for, offered for the purpose of, or represented as aiding persons with hearing loss. Annotation In general, hearing aids have internal microphones, amplifiers, and output transducers that are housed in the same physical unit and are air conduction devices. However, in some instances, the microphones and/or output transducers may be housed externally. Hearing aids are fit using audiometric and prescriptive methods.
circumaural earphone
7.16 circumaural earphone. Earphone which encloses the pinna and rests on the surrounding surface of the head. Annotation Contact with the head is normally maintained by compliant cushions. Circumaural earphones may touch but should not significantly compress the pinna.
earphone
7.15 earphone. Electroacoustic transducer intended to be closely coupled to the ear.