A noise-attenuating enclosure for audiometer earphones.

Noise-excluding earphones may be subdivided into circumaural earphones and noise-attenuating earphone enclosures. Two versions of 'Otocups', an example of the latter subdivision, were evaluated in a series of experiments and in comparison with a conventional type of earphone (Telephonics TDH-39 receiver in a MX-4I /AR cushion). The experiments involved a comparison of auditory threshold, artificialear measurements, test-retest reliability, and pure-tone attenuation. The second version of 'Otocups' was considered sufficiently reliable for most purposes and to have practical applications in industrial and clinical audiometry when proper booths are not possible on account of cost, weight, or space factors.