Semin Hear 2003; 24(4): 299-312
DOI: 10.1055/s-2004-815552
Copyright © 2003 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA. Tel.: +1(212) 584-4662

Earmold Acoustics

Mead C. Killion
  • President, Etymotic Research, Inc., Elk Grove Village, Illinois
Further Information

Publication History

Publication Date:
15 January 2004 (online)


Several fitting disappointments can be traced directly to improper earmold acoustics introduced by the earmold impression, or the instructions to the earmold laboratory, or to the earmold laboratory itself. To understand these disappointments requires some understanding of why earmolds do what they do to the sound passing through them. The reader possessing a certain eagerness to learn may find the present description (labeled theory) novel and useful. Following that theoretical description, an argument is made that many of the problems of occlusion effect and feedback can be alleviated by the proper use of a comfortable deeply-sealed earmold (requiring good impressions beyond the second bend, of course). The performance of actual earmolds is used throughout to illustrate the points made here.


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