Advertisement
...cont'd
Participants
12 2nd Grade Classes
128 male
114 female
Mean age: 6 years 8 months
43% were from an ethnic background (Vietnamese, Samoan, Spanish,
Aboriginal and Torres Strait Islander)
Equipment
NAL Twin FM Sound-field Amplification Systems (Type 3032) featuring:
2 Lapel Microphone/Transmitters
Volume controls set to the highest level
4 - 8 Ohm Speakers mounted on the wall
Teachers were given an information booklet outlining the project and rationale of
using sound-field amplification. Teachers also received in-service training
addressing classroom acoustics, speech perception difficulties, suggestions for
management and practical demonstration of the sound-field amplification
systems.
Audiological Assessment
Hearing screenings were performed on all the subjects at the beginning of the
school year. The same screenings were performed on 25% of the children mid-
year and at the end of the year.
Classroom Acoustic Measurements
Classroom acoustic measurements were carried out in each of the twelve
classrooms. The following calculations were made:
a) ambient noise levels
b) classroom RT measurements,
c) S/N ratios in unamplified classrooms
d) S/N ratios in amplified classrooms.
Occupied classroom noise measurements and S/N ratio calculations were
obtained during class time when the teachers and children were in their usual
positions during instructional teaching.
Continued....
Advertisement
