Overview
IEC TS 62886:2016 - Electroacoustics: Hearing aids - Method for measuring electroacoustic performance up to 16 kHz specifies a coupler and measurement methods to characterize the high‑frequency electroacoustic performance of hearing aids and insert earphones, with emphasis on the extended range from about 8 kHz up to 16 kHz. Published by the IEC (Technical Committee 29), this Technical Specification defines the mechanical design, calibration, coupling arrangements and uncertainty requirements for reliable laboratory measurements beyond the range of many existing couplers.
Key topics
- 0.4 cm coupler design: mechanical configuration, cavity dimensions, effective coupler volume and verification procedures for high‑frequency response.
- Calibration and reference conditions: environmental references and step‑by‑step calibration procedures to ensure comparable results across test labs.
- Coupling methods: specific procedures for attaching receivers, RIC, BTE and ITE hearing aids, earmould simulators and thin tubing to the 0.4 cm coupler.
- Transfer impedance and acoustic modelling: measurement and modelling of coupler transfer impedance, including electrical analogue (tube) models and impedance × frequency characteristics.
- Measurement protocols: test enclosure/equipment guidance, extended frequency THD measurement up to 16 kHz, data presentation (raw and normalized), and maximum permitted expanded uncertainty for conformance testing.
- Comparative transforms and annexes: informative transforms between the 0.4 cm coupler, the conventional 2 cm coupler and the occluded‑ear simulator; annexes cover transform data for different fittings and detailed transfer‑impedance test methods.
Applications and practical value
- Standardizes high‑frequency electroacoustic measurement methods so manufacturers and test labs can produce repeatable, comparable performance data up to 16 kHz.
- Supports product development and quality control for hearing aid receivers, in‑ear devices and insert earphones that include high‑frequency features.
- Enables regulatory and conformity assessment bodies to evaluate extended‑bandwidth performance with defined uncertainty limits.
- Facilitates research into audibility, fitting algorithms and high‑frequency hearing aid effects by providing validated coupler measurements and transforms to human ear simulators.
Who should use this standard
- Hearing aid and earphone manufacturers
- Accredited acoustic test laboratories
- Audiology researchers and product development teams
- Regulatory bodies and conformity assessment organizations
Related standards
- Complementary measurement references include the 2 cm coupler and occluded‑ear simulator comparisons documented within IEC TS 62886:2016. Users should consult IEC publications from TC 29 for broader electroacoustic measurement standards and guidance.
Keywords: IEC TS 62886:2016, electroacoustics, hearing aids, 0.4 cm coupler, measurement up to 16 kHz, transfer impedance, calibration, total harmonic distortion.