| 摘要 |
A kit of electronic parts designed for self fitting to passive ear muffs. The kit provides means for electronic sound enhancement such that, with the earmuffs in place over the ears, wanted sounds are heard at normal levels under quiet conditions. However the ear muffs revert to their original hearing protection state when subjected to ambient noise or impulse noise pressures of an uncomfortable or damaging level. The kit of parts comprises an electronic circuit suitably housed 1, loudspeakers or earpieces 2, means of connecting the loudspeakers or earpieces to the electronics e.g. conducting cables, forms of magnetic or electromagnetic or acoustic coupling 3, a portable power source 4 and a fitting kit (not shown). <IMAGE> |
