{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T22:24:33Z","timestamp":1767651873300},"reference-count":23,"publisher":"American Speech Language Hearing Association","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Am J Audiol"],"published-print":{"date-parts":[[1993,7]]},"abstract":"<jats:p>Mainly because of packaging size limitations, most amplifiers for in-the-ear (ITE) and in-the-canal (ITC) hearing aids have performed linear processing and had a class A output stage. Recent advances in the miniaturization of analog semiconductor technology have made it possible to package much more sophisticated signal processing circuitry and push-pull and class D output stages in ITE and ITC hearing aids.<\/jats:p>\n          <jats:p>These advancements have been used in hearing aids to improve sound quality, enhance the speech signal to emphasize weak consonants, provide increased flexibility in frequency response shaping, and reduce the amplification of undesired noise. Although digital programmability offers increased flexibility in hearing aid fittings, in most programmable hearing aid designs it is the analog portion of the circuit rather than the digital portion that performs the signal processing functions.<\/jats:p>\n          <jats:p>Although \"true\" digital signal processing holds promise for further dramatic improvements in hearing aid performance, the capabilities of analog electronics are just beginning to be exploited. Through advances in low-voltage CMOS circuitry, analog ITE and even ITC hearing aids are now being made with multiband amplifiers that have relatively steep filter slopes.<\/jats:p>\n          <jats:p>These small, nonprogrammable hearing instruments are essentially master hearing aids for frequency response shaping that require only a few potentiometers and an ordinary screw-driver for adjustment. Consequently, analog circuitry should not be totally abandoned as yet in favor of digital circuitry.<\/jats:p>","DOI":"10.1044\/1059-0889.0202.29","type":"journal-article","created":{"date-parts":[[2014,7,29]],"date-time":"2014-07-29T21:47:09Z","timestamp":1406670429000},"page":"29-40","source":"Crossref","is-referenced-by-count":3,"title":["Flexibility in Frequency Response Shaping and Signal Processing With Analog Hearing Aids"],"prefix":"10.1044","volume":"2","author":[{"given":"David A.","family":"Preves","sequence":"first","affiliation":[{"name":"Argosy Electronics, Inc., 10300 West 70th Street, Eden Prairie, MN 55344"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1310","reference":[{"key":"e_1_3_2_2_1","unstructured":"ANSI. (1992). American National Standards Institute S3.42-1992. 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Statistical Reporting Program","author":"HIA","year":"1992"},{"key":"e_1_3_2_10_1","volume-title":"Report from Center for Research in the Speech and Hearing Sciences","author":"Kates J.","year":"1990"},{"issue":"8","key":"e_1_3_2_11_1","first-page":"24","article-title":"Classifying automatic signal processors","volume":"41","author":"Killion M.","year":"1990","journal-title":"Hearing Instruments"},{"key":"e_1_3_2_12_1","first-page":"33","article-title":"Acoustic notch filters for hearing aids","volume":"4","author":"McCrae J.","year":"1982","journal-title":"Australian Journal of Audiology"},{"key":"e_1_3_2_13_1","first-page":"53","volume-title":"The Vanderbilt Hearing-Aid Report II","author":"Olsen W.","year":"1991"},{"issue":"4","key":"e_1_3_2_14_1","first-page":"103","article-title":"Multimicrophone adaptive beamforming for interference reduction in hearing aids","volume":"24","author":"Peterson P.","year":"1987","journal-title":"Journal of Rehabilitation Research and Development"},{"issue":"10","key":"e_1_3_2_15_1","first-page":"21","article-title":"The headroom problem and hearing aid performance","volume":"42","author":"Preves D.","year":"1989","journal-title":"Hearing Journal"},{"key":"e_1_3_2_16_1","first-page":"56","article-title":"Expressing hearing aid noise and distortion with coherence measurements","author":"Preves D.","year":"1990","journal-title":"Asha"},{"key":"e_1_3_2_17_1","first-page":"139s","volume-title":"Ear and Hearing","author":"Preves D.","year":"1991"},{"issue":"1","key":"e_1_3_2_18_1","doi-asserted-by":"crossref","first-page":"354","DOI":"10.1121\/1.402778","article-title":"Potential benefits of adaptive frequency-gain characteristics for speech reception in noise","volume":"91","author":"Rankovic C.","year":"1992","journal-title":"Journal of the Acoustical Society of America"},{"key":"e_1_3_2_19_1","unstructured":"Sammeth C. 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Study and development of the INTEL technique for improving speech intelligibility. Final Report NSC-m\/4-23. Madison WI: Nicolet Scientific Corp."},{"key":"e_1_3_2_24_1","first-page":"93","volume-title":"Journal of Rehabilitation Research and Development","author":"Weiss M.","year":"1987"}],"container-title":["American Journal of Audiology"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/pubs.asha.org\/doi\/pdf\/10.1044\/1059-0889.0202.29","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,4,18]],"date-time":"2021-04-18T22:01:16Z","timestamp":1618783276000},"score":1,"resource":{"primary":{"URL":"http:\/\/pubs.asha.org\/doi\/10.1044\/1059-0889.0202.29"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1993,7]]},"references-count":23,"journal-issue":{"issue":"2","published-print":{"date-parts":[[1993,7]]}},"alternative-id":["10.1044\/1059-0889.0202.29"],"URL":"https:\/\/doi.org\/10.1044\/1059-0889.0202.29","relation":{},"ISSN":["1059-0889","1558-9137"],"issn-type":[{"value":"1059-0889","type":"print"},{"value":"1558-9137","type":"electronic"}],"subject":[],"published":{"date-parts":[[1993,7]]}}}