Hearing Aid Terminology Regarding Phones


Next, I would like to explain what some of the different phone “Vocabulary Words” mean in the hearing aid world, because it can be confusing when you are trying to pick out a hearing aid.

Telecoil: (also known as T-coil).  A telecoil is a tiny coil of wire that will induce an electrical current in the coil when it is near a changing magnetic field, like a landline phone.  Telecoils also work with induction loop systems that are present in some theaters, churches, and meeting rooms, or with a neckloop.   Normally, when you hear through a hearing aid, you are hearing sounds that have been processed through the hearing aid’s microphone system, but when you switch to the telecoil setting (usually by touching the program button or flipping the toggle switch), the input comes from the telecoil and you “hear” the sound through a magnetic signal.  Telecoils make a buzzing sound when they are activated but you are not near a magnetic signal, or if the magnetic signal isn’t strong enough.  By moving a landline phone around near your hearing aid with a telecoil, you will be able to determine which position for holding the phone provides you with the most clarity.

This is what a telecoil looks like:


They are very tiny and not all sizes of hearing aids can accommodate telecoils.

If you attend movie theaters, churches, theaters, auditoriums, or sports stadiums, ask at the door if they have Assistive Listening Systems or a loop system that works with hearing aids.  You will be given some headsets or receivers on loan to help you to improve your hearing in these settings.

Telecoils do not always work well with cordless phones or cellular phones due to the lack of strength in the phone’s magnetic signal.  We recommend looking for a phone that says it is “HAC”, or “Hearing Aid Compatible” when you are buying.  Look for this marking on the package:

Auto T-Coil: An Auto T-Coil or Automatic T-coil is available on some hearing aids.  The “auto” means that you do not have to push a button to activate the t-coil, all you have to do is hold the phone up to your ear and the hearing aid should recognize the magnetic field and switch your hearing aid to the telecoil setting for processing.  These auto telecoils are improving all the time, but do not always work as you would like them to.  You will probably find that your hearing on every phone is different and you will prefer certain phones over others because the sound will be clearer to you.


In the next blog, we will discuss more “Phone Technology”, specifically cell phones, Bluetooth, and how it all works together!


Until next time,

Dr. Kristin