Show dont talk so loud when mien speaking to the deaf iowa iova city iowa deal deaf people do not enjoy loud talk when allowed to adjust the loudness ot of the voice to which they are listening individuals with normal ears prefer to have it 38 decibels or loudness units above the level at which it Is audible hard ot of hearing persons will adjust the same speech at a loudness only 23 to 20 deci decilles bles above their threshold of hearing this was discovered in experiments peri ments at the university of iowa by dr noble 11 kelley deaf ears function differently diff brently from normal cars dr kelley found in speaking to those with normal hearing you will have most in making your consonant sounds understood vowel sounds are most intelligible for tho the deafened the consonants are recognized practically as 83 easily as the vowels t |