Hearing aid with permanently adjusted frequency response

• US 5,406,633 A
• Filed: 11/03/1992
• Issued: 04/11/1995
• Est. Priority Date: 11/03/1992
• Status: Expired due to Fees

• Current Assignee: Auditory System Technologies, Inc.
• Original Assignee: Auditory System Technologies, Inc.
• Inventors: Miller, Kenneth R., Taylor, James C., Fuller, Lynn F., Walton, Joseph P., Frisina, Robert D.
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): TRAN, SINH N
• Application Number:
  US07/970,628
• Time in Patent Office: 889 Days
• Field of Search: 381/68, 381/104, 381/71, 381/94, 381/68.2, 381/68.4, 381/69
• US Class Current: 381/320
• CPC Class Codes: H03H 11/0422 using transconductance amplifiers, e.g. gmC filters
• CPC Class Codes: H04R 25/356 Amplitude, e.g. amplitude shift or compression
• CPC Class Codes: H04R 25/502 using analog signal processing
• CPC Class Codes: H04R 25/70 Adaptation of deaf aid to hearing loss, e.g. initial electronic fitting
• CPC Class Codes: H04R 3/04 for correcting frequency response

Abstract

A hearing aid is permanently adjusted to match prescribed amplification characteristics at predetermined frequencies. A single channel filter (24) includes three identical filter stages (60, 62, and 64) that are optionally cascaded in series. Each of the filter stages (60, 62, and 64) exhibits a frequency response curve having a first corner frequency (36) below which the magnitude of the response curve approaches a predetermined minimum value, a second corner frequency (38) above which the magnitude of the response curve approaches a maximum value, and a predetermined gain in magnitude between the minimum and maximum values.

Claims