In order to study effectiveness of low-frequency amplification and filtered-speech testing for preschool deaf children, an experimental design permitting the teacher to speak simultaneously through two different amplifying systems, a low-frequency auditory training unit (Suvag I) and a conventional auditory training unit (Warren T-2), was used…

During a 3-year period, 20 preschool deaf children were matched and given auditory training by the Verbo-tonal method using two different amplification systems (one which amplified from 200 to 5000 hertz and the other from 20 to 5000 hertz). There were three main goals: (1) to compare two different amplification systems to determine if the…