The Effects of High-Cutoff Filtered Noise Upon the Intelligibility of Different Speech Materials in a Closed-Response Set
Allen C. Busch, Donald H. Eldredge · The Journal of the Acoustical Society of America · 1967
House, Williams, Hecker, and Kryter [J. Acoust. Soc. Am. 37, 158–166 (1965)] have pointed out that while the Modified Rhyme Test (MRT) is a highly repeatable, stable test, its only drawback is that it is less capable than open-format tests of discriminating among highly intelligible communications systems. An experiment was performed to determine whether the discrimination function of the closed-response format would be altered by the introduction of different speech materials into the closed-response sets. The MRT and a 9-choice nonsense-syllable, closed-response test were administered to subjects under five types of high-cutoff filtered noise to 1500 Hz, 2120 Hz, 3000 Hz, 6800 Hz (speech-shaped), and 6800 Hz (flat Gaussian)—at six S/N ratios. The results indicated that a significant increase in the discrimination function resulted from the 9-choice nonsense materials but that no real differences resulted in the slope of the function. Both the MRT and the 9-choice test showed the same effects relative to each other and between noise types.