ELECTROACOUSTICS - HEARING AIDS - PART 8: METHODS OF MEASUREMENT OF PERFORMANCE CHARACTERISTICS OF HEARING AIDS UNDER SIMULATED IN SITU WORKING CONDITIONS
International Electrotechnical Committee
FOREWORD<br>INTRODUCTION<br>1 Scope<br>2 Normative references<br>3 Terms and definitions<br>4 Limitations<br>5 Test equipment<br> 5.1 Acoustical requirements for the test space<br> 5.2 Sound source<br> 5.3 Manikin<br> 5.4 Ear simulator<br> 5.5 Ear insert simulator<br> 5.6 Equipment for the measurement of occluded-ear <br> simulator sound pressure level<br> 5.7 Equipment for automatic sweep frequency recording<br> 5.8 Equipment for calibration of free field sound <br> pressure level<br>6 Test conditions<br> 6.1 Choice of test point<br> 6.2 Ambient conditions<br> 6.3 Manikin<br> 6.4 Location of the hearing aid<br> 6.5 Normal operating conditions for the hearing aid<br>7 Measurements<br> 7.1 General<br> 7.2 Adjustment of the reference input sound pressure <br> level <br> 7.3 Manikin frequency response (MFR)<br> 7.4 Full-on simulated insertion gain measured by the <br> constant reference input SPL method<br> 7.5 Full-on simulated insertion gain measured by the <br> constant ear simulator SPL method<br> 7.6 Directional characteristics<br> 7.7 Simulated in situ OSPL90 measurements<br> 7.8 Simplified method to measure simulated in situ and <br> insertion gain response<br>8 Frequency response recording charts<br>9 Maximum permitted expanded uncertainty of measurements<br>Annex A (normative) Free-field to hearing-aid-microphone <br> transformation<br>Annex B (normative) Manikin unoccluded-ear gain (open ear <br> response)<br>Annex C (informative) General requirements for a manikin<br>Bibliography
Specifies the methods for a test which simulates the acoustical effects of a median adult wearer on the performance of a hearing aid.
| Document Type | Standard |
| Status | Current |
| Publisher | International Electrotechnical Committee |
| Committee | TC 29 |
