Hearing Loops: Basic Troubleshooting
Please don’t discount hearing assistance in buildings, but rather check with staff to see that the system and devices are turned on and operating, much as wheelchair ramps need to be kept open. Any assistive listening will not work unless turned on.
If the system is turned on and there is no sound, contact a knowledgeable hearing loop installer for analysis.
Common Troubleshooting (for Sites)
Use a hearing loop receiver and headphones to listen. It’s a good practice to test weekly and verify during a microphone test before every event. It takes less than a minute. A test just before an event may be too late to troubleshoot.
Every site should have hearing loop receivers for people who do not have hearing aids or people with hearing aids and no telecoils. The number of receivers is based on the capacity. Receiver calculator Northwest ADA Center (website). Battery and rechargeable (Contacta website) receivers are available as well as receivers with testing device (Univox website)
With the Univox receiver/testing device: green indicates that the loop fulfills the international standard IEC 60118-4 level requirement. A yellow LED indicates that the loop is operational but does not meet the IEC level requirement, but will still benefit the user.
- Hearing loop driver plugged into an electrical outlet?
- Hearing loop driver turned on?
- Hearing loop driver connected to the audio mixer? (commonly there is a cord from the ‘audio out’ on the sound mixer to ‘audio in’ on the hearing loop driver).
- Hearing loop driver – are the hearing loop output connections are still connected to the driver?
- Audio mixer, many mixers are programmable. Check to see if the settings for the mixer audio output that feeds the hearing loop driver have not changed.
- If the hearing loop is still not working, contact a hearing loop installer who is skilled in troubleshooting.
Why Meet the IEC Standard for Hearing Loop System Installation? HLAA-Hearing Loss Association of America (2 pages, pdf)
Buzzing is caused by EMI, not the hearing loop. See EMI Glossary
- How to Find EMI. Contacta (3 pages, pdf)
Please see Hearing Loop Maintenance Guidelines by University of Virginia (UVA)
Probably the hearing loop is a perimeter loop and not a phased array. Contact a knowledgeable hearing loop installer.
See hearing loop diagrams (this website)
With a hearing loop, there should be no delay (latency). Contact a knowledgeable hearing loop installer to analyze and solve the problem.
Resources
- ILHMA (International Hearing Loop Manufacturers Association) Various standards, including IEC standards, Code of practice for hearing-loop systems, Wireless Microphones, Electroacoustics – Audio-frequency induction loop systems for assisted hearing (webpage)
- Why Meet the IEC Standard for Hearing Loop System Installation? HLAA-Hearing Loss Association of America (2 pages, pdf)
- Theater or Concert Hall Sound Mixing for People with Hearing Loss HLAA Reprinted with permission Richard Einhorn, 2015 (2 pages, pdf)