Abstract:An enclosure has been constructed to evaluate the performance of active noise reduction (ANR), circumaural head sets, and hearing protectors, at frequencies below 800 Hz. It consists of a massive (5-kg), flat base plate against which one cup cushion is sealed by spring pressure. The sound pressure within the cup is recorded by a microphone flush-mounted in the base plate. A 20-cm-diam aluminum tube, 20 cm in length, is attached by annular flanges to the base plate at one end and, at the other, to a 15-cm-diam … Show more
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.