US Patent 9538298 Attenuating tip for hearing aid

A hearing aid includes a speaker in a tip that is located in an ear canal. The tip includes a coupling, a retainer that mechanically engages the coupling, and a sleeve axially surrounding the retainer. The retainer attenuates lower frequencies than are attenuated by the sleeve. The sleeve is preferably a foam rubber and the retainer is preferably a composite material. A flange on the retainer reflects sound back into the sleeve for additional attenuation. It has been discovered that operation is improved if the outside diameter of the sleeve and the outside diameter of the retainer are in the ratio of approximately 1.75:1.