Pure level changes are rated as valuable as SNR changes despite not aiding intelligibility

Evidence

For the remaining 30 participants, the results are very similar to those for SNR, though ΔLs of 4–8 dB were rated modestly higher than ΔSNRs of 4–8 dB. That is, a change in level without a change in SNR was considered as good as—indeed if not better than—a change in SNR. While this finding does not coincide with their role in intelligibility, it is coincident with detectability of level and SNR changes (JNDs of 1.5 and 3.0 dB, respectively). — Dijk, Pim van, Physiology, Psychoacoustics and…, 5686

Categorization

Category: Contrarian or Surprising Claims

• SEED: Article angle: listeners’ subjective valuation of hearing-aid ‘benefit’ tracks detectability, not actual intelligibility gains — a cautionary tale for device marketing claims.

Related

• Listeners may judge SNR changes via perceived intelligibility rather than raw signal level (similarity 0.92)
• Listeners value a level change as much or more than an equal-dB SNR change (similarity 0.91)
• Listeners value loudness increases as much as SNR improvements they provide (similarity 0.90)
• Listeners’ SNR JNDs may actually be intelligibility JNDs, not signal-level ones. (similarity 0.90)
• A 3 dB SNR just-noticeable difference corresponds to a 26% intelligibility change in listeners. (similarity 0.88)
• A 1 dB SNR improvement boosts intelligibility by 7 to 19 percent (similarity 0.87)
• Hearing aid SNR improvements fall below the just-noticeable threshold for speech understanding (similarity 0.86)
• Detectable changes in speech SNR correspond to roughly 26 percent changes in word intelligibility (similarity 0.86)
• Very high speech levels can reduce word recognition scores. (similarity 0.86)
• Hearing-aid benefit studies lack an agreed threshold for meaningful SNR improvement (similarity 0.85)
• The just noticeable difference in signal-to-noise ratio for speech is about 3 dB (similarity 0.85)
• A 1 dB SNR improvement raises speech intelligibility by 7 to 19 percent. (similarity 0.85)
• Listeners benefit from but do not fully use broadband spectral information. (similarity 0.85)
• SNR just-noticeable difference grows from about 3 to 3.7 dB at positive reference SNRs (similarity 0.85)
• Current hearing aids cannot produce SNR improvements exceeding the meaningful-benefit threshold in real environments. (similarity 0.84)

Broader Connections

• Pitch strength and loudness scale at sharply different rates with level changes. #exemplifies (0.75) — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 805