Abstract

Earphones and headphones are frequently used in noisy areas where the environmental noise can mask the signal reproduced. When using earphones or headphones that provide weak or no sound insulation, it will be necessary to increase the sound levels of reproduction and this may expose the listener to harmful levels. By the other hand, the headphones that provide a good sound insulation allow to listen properly the reproduced sound signal even at lower levels. This work measures the insertion loss of several models of earphones and headphones of different types: button, in-ear, supra-aural and circumaural. The measurements were made using a dummy head Kemar 45BM and a sound analyzer Svantek 959. The measurement methodology was based on the ISO 4869-3 standard for evaluating hearing protectors. It was found that the headphones from the circumaural type and in-ear earphones are those that provide greater sound insulation. Most of the evaluated type button and supra-aural headsets offer a poor or negligible sound insulation.