Already a subscriber?
MADCAD.com Free Trial
Sign up for a 3 day free trial to explore the MADCAD.com interface, PLUS access the
2009 International Building Code to see how it all works.
If you like to setup a quick demo, let us know at support@madcad.com
or +1 800.798.9296 and we will be happy to schedule a webinar for you.
Security check
Please login to your personal account to use this feature.
Please login to your authorized staff account to use this feature.
Are you sure you want to empty the cart?
PD IEC/TS 62886:2016 Electroacoustics. Hearing aids. Method for measuring electroacoustic performance up to 16 kHz, 2016
- 30315344-VOR.pdf [Go to Page]
- CONTENTS
- FOREWORD
- INTRODUCTION
- 1 Scope
- 2 Normative references
- 3 Terms, definitions and abbreviated terms [Go to Page]
- 3.1 Terms and definitions
- 3.2 Abbreviated terms
- 4 Mechanical design of the 0,4 cm3 coupler [Go to Page]
- 4.1 General
- 4.2 Cavity dimensions [Go to Page]
- 4.2.1 Critical dimensions
- 4.2.2 Effective coupler volume
- 4.2.3 Diameter of the coupler cavity
- 4.3 Verification procedure of the effective coupler volume [Go to Page]
- 4.3.1 General
- 4.3.2 Test set-up
- 4.3.3 Effective volume of the coupler under test
- 4.4 Measuring microphone [Go to Page]
- 4.4.1 General
- 4.4.2 Preferred microphone
- 4.4.3 Alternative microphones
- 4.5 Static pressure equalisation vent
- 5 Calibration [Go to Page]
- 5.1 Reference environmental conditions
- 5.2 Calibration procedure
- 6 Coupling of receivers and hearing aids to the coupler [Go to Page]
- 6.1 Coupling to a hearing aid receiver by means of tubing
- 6.2 Coupling to a hearing aid embedded in or connected to an earmould
- 6.3 Coupling to a receiver in the canal (RIC hearing aid)
- 6.4 Coupling to a BTE hearing aid with 2 mm continuous internal diameter tubing
- 6.5 Coupling to a BTE hearing aid with earmould simulator
- 6.6 Coupling to a BTE hearing aid with thin tubing
- 7 Transfer impedance of the 0,4 cm3 coupler
- 8 Comparison of the 0,4 cm3, the 2 cm3 coupler and the occluded-ear simulator [Go to Page]
- 8.1 Sound pressure level frequency response curves
- 8.2 Comparison of the coupler impedance with typical source impedances
- 8.3 Influence of sound source impedance on measured level difference between the 0,4 cm3 coupler and the 2 cm3 coupler
- 9 Maximum permitted expanded uncertainty for coupler conformance testing
- 10 Measurements using the 0,4 cm3 coupler [Go to Page]
- 10.1 General
- 10.2 Test enclosure and test equipment
- 10.3 Extended frequency range for total harmonic distortion measurements
- 10.4 Presentation of data [Go to Page]
- 10.4.1 General
- 10.4.2 Presentation as 0,4 cm3 coupler data
- 10.4.3 Presentation as normalised to 2 cm3 coupler data
- 10.5 Maximum permitted expanded uncertainty of measurements performed using the 0,4 cm3 coupler
- Annex A (informative) Response transforms between the 0,4 cm3 coupler and the occluded-ear simulator [Go to Page]
- A.1 General
- A.2 Simulation model of the human ear and approximation of λ/2 resonances
- A.3 Measured and simulated transform responses of a standard-fitting
- A.4 Transform curves for CIC-fitting and deep-insertion-fitting
- Annex B (informative) Measurement and modelling of the transfer impedance of the 0,4 cm3 coupler [Go to Page]
- B.1 Measurement procedure [Go to Page]
- B.1.1 Transfer impedance
- B.1.2 Calibration of the volume velocity source at 250 Hz
- B.1.3 Calibration of the volume velocity source over the frequency range from 100 Hz to 60 kHz
- B.1.4 Test set-up for measuring the coupler transfer impedance
- B.2 Measurement of the coupler transfer impedance
- B.3 Electrical analogue representation of the coupler as a tube model
- Bibliography
- Figures [Go to Page]
- Figure 1 – Mechanical design of the 0,4 cm3 coupler, shown with removable coupling plate with a nipple for the attachment of coupling tubing
- Figure 2 – Coupling to a hearing aid receiver by means of coupling tubing
- Figure 3 – Coupling to an ITE hearing aid
- Figure 4 – Coupling to a receiver in the canal (RIC hearing aid)
- Figure 5 – Coupling to a BTE hearing aid with 2 mm continuous internal diameter tubing
- Figure 6 – Coupling to a BTE hearing aid with earmould simulator
- Figure 7 – Coupling to a BTE hearing aid with thin coupling tubing
- Figure 8 – Magnitude frequency response of the transfer impedance frequency and the related equivalent volume
- Figure 9 – Comparative measurement of the 0,4 cm3 coupler, the 2 cm3 coupler and the occluded-ear simulator frequency responses
- Figure 10 – Magnitude frequency responses of acoustic impedance of the 2 cm3, the 0,4 cm3 coupler and various hearing aid types
- Figure 11 – Deviation from the normalized coupler volume ratio as a function of the effective volume of the sound source Vs
- Figure A.1 – Electrical analogue model of the human ear
- Figure A.2 – Measured transform response of a standard-fitting
- Figure A.3 – Comparison between the measured and the simulated standard-fitting transform response
- Figure A.4 – Transform responses for (a) standard-fitting, b) CIC-fittingand (c) deep-insertion-fitting
- Figure B.1 – Test set-up for measuring the coupler transfer impedance
- Figure B.2 – Average frequency response of 8 coupler measurements
- Figure B.3 – Average transfer impedance of the 0,4 cm3 coupler
- Figure B.4 – Transfer impedance times frequency re 1 Pa/m3 in dB and as equivalent volume in mm3 in the frequency range 100 Hz to 60 kHz
- Figure B.5 – Electrical analogue model based on a tube model
- Figure B.6 – Comparison between the measured (solid line) and the simulated(dashed line) transfer impedance
- Figure B.7 – Frequency responses of simulated 0,4 cm3 coupler inputand transfer impedances
- Tables [Go to Page]
- Table 1 – Values of Umax for basic measurements
- Table 2 – Distortion test frequencies and input sound pressure levels
- Table 3 – Values of Umax for basic measurements
- Table A.1 – Transform data for standard-fitting (fitting at reference plane), CIC-fitting and deep-insertion-fitting
- Table B.1 – Transfer impedance of the 0,4 cm3 coupler in the frequency range from 100 Hz to 60 kHz [Go to Page]