Comparison of amplification systems in a classroom

Summary

Compared word recognition through an induction loop, an FM system, an infrared system and a public-address system in a medium-size classroom.

Key findings

PubMed dates the article to January 1986. Its Grants and funding section lists NIH grant R01 NS 12035, and its publication types include US government research support.
Listener groups were people with normal hearing, people with hearing loss, hearing-aid users and older adults; words were tested with 12-voice babble at +8 dB and without babble at +20 dB.
For every group, all three assistive systems gave better word scores than the public-address system.
Differences between systems depended on the listener group and on the room signal-to-noise ratio; the authors conclude that all three systems suit listeners with various degrees of hearing loss.
The PubMed record classifies the paper as US Public Health Service-supported research and lists NIH/NINDS grant R01 NS 12035 under Grants and funding; the abstract does not state the participant count.

Limits

Only the PubMed abstract and bibliographic and grant metadata were read; the full paper was not obtained, and the abstract gives no participant count or equipment models. One classroom comparison published in 1986; word tests rather than sentences.

Read the original

pubmed.ncbi.nlm.nih.gov/3958997

Link checked 13 October 2026. We link to the original and do not host copies.

Cited in

What do listeners prefer, and how often do they use venue systems?Partly answered
Where does infrared assistive listening work, and where does it fall short?Partly answered
What works in university lecture halls and large teaching rooms?Partly answered
How much do room acoustics and distance limit listening without a system, and what follows for choosing one?Partly answered

Cite this source

Nábělek AK, Donahue AM, Letowski TR. Comparison of amplification systems in a classroom. Journal of Rehabilitation Research and Development 23(1):41-52. January 1986. https://pubmed.ncbi.nlm.nih.gov/3958997/ (accessed 13 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/nabelek-1986-classroom/

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