Telecoil
A telecoil (also written T-coil) is a small coil of wire built into many hearing aids and cochlear implant sound processors that picks up magnetic signals from compatible sound sources and converts them directly into electrical signals for amplification or processing. Unlike a standard microphone, which picks up acoustic sound from the surrounding environment, a telecoil receives a magnetically transmitted audio signal, which means it does not amplify background noise at the same time.
Telecoils are activated when the hearing aid user selects the T (telecoil) program or the MT (microphone plus telecoil) program on their device. Compatible sound sources include telecoil-enabled hearing loops (also called audio induction loops), which are installed in many public venues including theatres, places of worship, ticket counters, and government offices, and which broadcast the audio signal (from a microphone or sound system) as a magnetic field that fills the looped area. Telecoils also allow users to hear more clearly when using compatible landline telephones, which generate a magnetic signal from the earpiece.
In Canada, the installation of hearing loops in public spaces is encouraged under accessibility legislation and guidelines, and telecoil-compatible hearing aids are eligible for funding through the Assistive Devices Program (ADP). When choosing a hearing aid, users who frequently use looped venues or public phones should confirm that the selected device includes a telecoil and that it is programmed and activated. Not all hearing aid styles include a telecoil: very small canal devices (IIC and some CIC styles) often cannot accommodate one due to their size.
