Optimum Loudness for Obtaining Maximum Speech Recognition Score

To estimate the optimum loudness for obtaining maximum speech recognition score, we carried out speech discrimination test on 124 ears with sensorineural hearing loss by the use of 67-S monosyllable list. Every time just after one list was tested each subject was asked to evaluate the loudness of the test speech sound using seven steps categorical scale. As an index of optimum speech loudness, the ratio of the ears was calculated in which the maximum recognition score within 5% was obtained at the speech level with the every loudness category. The ratio showed maximum at the category 5 (“comfortable, but slightly loud”), but there was no significant difference in the ratio between category 5 and category 4 (“comfortable”) or 6 (“loud”). Comparison by the type of auioram showed that the same results were obtained in each type group of audioram, and in the group of low tone hearing loss type audioram the ratio was higher at the levels with low loudness rating (2: “soft” or 3: “comfortable, but slightly soft”) than in the groups of flat type or higr-tone hearing loss type audiogramn.