The SII model mispredicts intelligibility of sharply filtered speech and noise

Evidence

The floor/ceiling values observed in these experiments are not in agreement with the SII assumptions, except when the target was HP-filtered. In this specific case, the results suggested a floor value at 13-dB attenuation. The results from the other experiments suggested a larger range of SNRs contributing to speech intelligibility [‑37 dB; 43 dB]. When the target is filtered, the floor value seemed to be frequency-dependent in contrast to the SII approach which proposes the same SNR range in each frequency band. — Dijk, Pim van, Physiology, Psychoacoustics and…, 3581

Categorization

• DEFINE: Clarifies what the Speech Intelligibility Index (SII) assumes versus what measured data show.