Induction Hearing Loops – Assistive Hearing Devices

How A Loop WorksThe room or space has a wire loop or several loop arrays installed. These are connected to a special amplifer and to microphones or computer audio output. The listener turns on the T-Coil or Telecoil in their hearing Aid or other T-Coil listening device in order to hear. The sound of the presenter (or music program) is greatly enhanced while, Background noise is reduced allowing very clear hearing.

How a Loop Works

  1. The presenter has a microphone – wireless or with cord
  2. The microphone is hooked up to an amplifier
  3. The amplifier sends an electrical signal through a wire around the room
  4. The current flowing in the wire creates a magnetic field
  5. The magnetic field flows through the room
  6. A person with a tele coil (T-coil) in their hearing aid turns the T-coil on
  7. The T-coil picks up the magnetic signal and generates an electrical signal
  8. The electrical signal is amplified by the hearing aid and is provided into the user’s ear

Advantages

  • Clear sound
  • The people with T-coils can hear the presenter very clearly and as loud as they would like
  • Turning the T-coil on – turns the microphone in the Hearing Aid off, so the sound of the presenter’s voice will be much louder than any background noise (which is no longer amplified
  • The people with hearing aids with T-coils do not have to wear headsets (as with FM or Infra-Red systems), so no one in the room has to know that the person has a Hearing Loss
  • People can keep Hearing Loss hidden
  • The people with hearing aids with T-coils do not have to wear headsets (as with FM or Infra-Red systems) – so no one in the room has to know that the person has a Hearing Loss
  • People without hearing aids or who have hearing aids –without T-coils can also wear Assistive Listening Devices with ear phones and a pocket device (similar to FM or Infra-Red System).

 Disadvantages

  • An induction hearing loop must be installed in the floor or ceiling.
  • People without T Coils in their hearing aids must use a listening device and headphones.

FM (Frequency Modulation)

Frequency ModulationSystems use an FM or VHF Radio transmitter to send out the signal from the microphones or computer audio output. The listener turns on an FM listening device and listens using headphones. The sound of the presenter (or music program) is heard directly by the listener.

IR (InfraRed) Systems

The system uses an invisible light (Infra Red) to send outthe signal from the microphones or computer audio output. The listener turns on an IR listening device and listens using headphones.

How an FM or IR Transmission system works:

  1. The presenter has a microphone – wireless or with cord
  2. The microphone is hooked up to an amplifier and transmitter
  3. The transmitter sends a signal using FM – frequency modulation or IR – Infra-Red light
  4. A person with an FM or IR receiver picks up the signal
  5. The person hears the signal using headphones

 Advantages

  • Clear sound
  • The people with receivers can hear the presenter very clearly and as loud as they would like
  • The installation is simply a transmitter connected to the PA system

Disadvantages

  • Each person must wear a headset and have a receiver
  • The FM signal will travel outside the room
  • The IR signal – the person must be in sight of the IR transmitter

Captioning Systems

These use a screen to display the captions / visible words for those with hearing loss. The captions are similar to the CC function on TV or to captioned telephones. These systems are can be advantageous where there is loud background noise.

Advantages

  • People can read the captions
  • People do not need to identify themselves as having hearing loss
  • System installation is straight forward

Disadvantages

  • Cannot hear the presenter – any voice inflections or emphasis
  • Cannot hear music