Assistive Listening Knowledge Base
  • Peer-reviewed study (repeated measures, small sample)

Optimizing the benefit of sound processors coupled to personal FM systems

From https://assistivelisteningknowledgebase.org/evidence/wolfe-schafer-2008/ · record checked 9 October 2026

  • Wolfe J, Schafer EC
  • Journal of the American Academy of Audiology 19(8):585-594

Independent (first author at the Hearts for Hearing Foundation, Oklahoma City; PubMed tags the study as having non-US-government research support without naming it; the full text, with any funding statement, could not be read; the processors tested were Advanced Bionics')

Summary

Compared two settings for mixing a personal FM receiver's signal with the cochlear implant processor's microphone, 50/50 and 30/70, for adults with Advanced Bionics processors.

Key findings

  • Twelve adults using Advanced Bionics Auria processors were tested in quiet (35 and 50 dB HL) and in noise (+5 dB SNR), with and without a personal FM system, at two audio-mixing ratios, and answered questionnaires after two weeks with each ratio.
  • At 50/50 the processor microphone and the FM signal are weighted equally; at 30/70 the microphone signal is attenuated by 10 dB.
  • The FM system significantly improved speech recognition in quiet at low presentation levels and in noise, and perceived benefit in noise.
  • With 30/70, recognition of soft speech not directed to the FM transmitter was significantly poorer. Speech recognition in noise and functional benefit did not differ between the two ratios.
  • The authors recommend a 50/50 mixing ratio for FM use in quiet and noisy situations.

Limits

Read from the abstract only; the full text could not be read. Personal FM with one maker's processors of 2008, tested in a clinic: evidence about the input path and the mix, not a venue system. Twelve participants.

Read the original

doi.org/10.3766/jaaa.19.8.2

Link checked . We link to the original and do not host copies.

Cited in

Cite this source

Wolfe J, Schafer EC. Optimizing the benefit of sound processors coupled to personal FM systems. Journal of the American Academy of Audiology 19(8):585-594. September 2008. https://doi.org/10.3766/jaaa.19.8.2 (accessed 9 October 2026).

The accessed date is when this library last checked the link; use the date you read it. To point readers to this summary instead, link to https://assistivelisteningknowledgebase.org/evidence/wolfe-schafer-2008/

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