Headphones, Earphones, Hearables
Examples
Application
- Consumer and convenience applications
- Wireless and mobile communication devices
- Telecommunication
- Headsets
- Devices with Active Noise Cancellation (ANC)
- Hearing aids
Particularities
Headphones, earphones, hearables and hearing aids are designed to operate very close to the human ear having a completely different load condition compared to normal loudspeakers. Special test gear for mounting headphones and simulating the human ear is required. A reproducible and stable mounting is key for accurate testing.
Usually such devices are using wide bandwidth transducers with very light membranes and without spider. Thus, they are quite sensitive to mechanical damage and need to be tested for impulsive, irregular distortion (Rub&Buzz). Stereo balance, phase matching and sound leakage into the ambience are important criteria for headphone performance, especially for wireless audio interfaces. Headsets also require microphone testing in addition.
Critical Issues
- Max SPL level, hearing protection
- Rub & Buzz, air leakage noise and other impulsive distortion
- Stereo balance (difference between left and right channel)
- Leakage noise to ambience
- Damping of external noise (ANC performance)
- True wireless interface (phase match of left and right channel)
Standards
International Electrotechnical Commission
IEC 60268-7, Sound System Equipment, Part 7: Headphones and Earphones
IEC 60318-1, Electroacoustics - Simulators of Human Head and Ear - Part 1: Ear Simulator for the Measurement of Supra-aural and Circum-aural Earphones
Institute of Electrical and Electronics Engineers
IEEE 269-2010 Standard Methods for Measuring Transmission Performance of Analog and Digital Telephone Sets, Handsets, and Headsets
IEEE 1329 Standard Method for Measuring Transmission Performance of Handsfree Telephone Sets
European Standards
BS EN 50332
International Telecommunication Union
ITU-R Recommendation BS. 775-2 Multi-channel Stereophonic Sound System with and without Accompanying Picture
ITU-T P.581 Use of Head and Torso Simulator for Hands-free and Handset Terminal Testing
International Organization for Standardization
ISO 4869-3 Acoustics - Hearing protectors - Part 3: Measurement of insertion loss of ear-muff type protectors using an acoustic test fixture
