Assistive Listening Knowledge Base
  • Peer-reviewed study

Effects of spatial and temporal integration of a single early reflection on speech intelligibility

From https://assistivelisteningknowledgebase.org/evidence/warzybok-2013/ · record checked 9 October 2026

  • Warzybok A, Rennies J, Brand T, Doclo S, Kollmeier B
  • Journal of the Acoustical Society of America 133(1):269-282

Independent (Medical Physics, University of Oldenburg; the abstract names no funder, and PubMed indexes the work as non-US government research support)

Summary

Speech-in-noise tests with a talker's speech plus one delayed copy of it, at delays from 0 to 200 ms, to find when a late copy stops helping and starts to harm intelligibility.

Key findings

  • Measured speech reception thresholds with frontal target speech plus a single reflection of it delayed by 0 to 200 ms, varying the reflection's direction and whether the interfering noise came from the front, all around or one side.
  • With the reflection from the front, the delayed copy was fully integrated with the direct sound up to a delay of at least 25 ms, after which intelligibility gradually declined as the delay grew.
  • At 200 ms, the delayed copy made intelligibility worse than the direct sound alone.
  • When the delayed copy came from a different direction from the direct sound, the harm at 200 ms was reduced in every spatially separated condition tested.

Limits

Only the abstract was read; the full paper is behind the publisher's paywall, so the number of listeners, their hearing and the relative level of the delayed copy could not be checked (PubMed's indexing lists adults and young adults). Laboratory conditions with a single reflection; it does not test a stream from an assistive listening system or delays beyond 200 ms.

Read the original

pubmed.ncbi.nlm.nih.gov/23297901

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

Cited in

Cite this source

Warzybok A, Rennies J, Brand T, Doclo S, Kollmeier B. Effects of spatial and temporal integration of a single early reflection on speech intelligibility. Journal of the Acoustical Society of America 133(1):269-282. January 2013. https://pubmed.ncbi.nlm.nih.gov/23297901/ (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/warzybok-2013/

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