AS 60118.8-2007

1 - AS 60118.8-2007 Hearing aids Part 8: Methods of measurement of performance characteristics of hearing aids under simulated in situ working conditions
4 - PREFACE
5 - CONTENTS
6 - Introduction
7 - 1 Scope
7 - 2 Normative references
8 - 3 Terms and definitions
11 - 4 Limitations
11 - 5 Test equipment
11 - 5.1 Acoustical requirements for the test space
12 - 5.2 Sound source
12 - 5.3 Manikin
12 - 5.4 Ear simulator
12 - 5.5 Ear insert simulator
12 - 5.6 Equipment for the measurement of occluded-ear simulator sound pressure level
13 - 5.7 Equipment for automatic sweep frequency recording.
13 - 5.8 Equipment for calibration of free field sound pressure level.
13 - 6 Test conditions
13 - 6.1 Choice of test point.
14 - 6.2 Ambient conditions.
14 - 6.3 Manikin
14 - 6.4 Location of the hearing aid.
14 - 6.5 Normal operating conditions for the hearing aid
15 - 7 Measurements
15 - 7.1 General
15 - 7.2 Adjustment of the reference input sound pressure level
16 - 7.3 Manikin frequency response (MFR)
16 - 7.4 Full-on simulated insertion gain measured by the constant reference input SPL method
17 - 7.5 Full-on simulated insertion gain measured by the constant ear simulator SPL method
17 - 7.6 Directional characteristics
19 - 7.7 Simulated in situ OSPL90 measurements
20 - 7.8 Simplified method to measure simulated in situ and insertion gain response.
20 - 8 Frequency response recording charts
20 - 9 Maximum permitted expanded uncertainty of measurements
22 - Annex A (normative) Free-field to hearing-aid-microphone transformation
26 - Annex B (normative) Manikin unoccluded-ear gain (open ear response)
28 - Annex C (informative) General requirements for a manikin
31 - Bibliography