Along with the IEC 60118 Standard, which sets out the minimum acceptable performance criteria for hearing loops, the IEC have also published the IEC 62489 Standard, which stipulates how the performance of a driver is measured.
“IEC 62489… applies to the components of audio-frequency induction loop systems for assisted hearing… This standard is intended to encourage accurate and uniform presentation of manufacturers‘ specifications, which can be verified by standardized methods of measurement…“
To ensure you are providing a genuine benefit always purchase hearing loop drivers that are IEC 62489-1 compliant.
Caution: However, some manufacturers confusingly provide misleading information regarding performance parameters including:
- Current
IEC 62489-1 requires a measurement of capability with real signals and real loads. It is no longer acceptable to state currents for instantaneous peaks, as ‘peak to peak’ measurements, capability at very low frequencies, or capability with unrealistic (non-inductive / short circuit) loads. - Voltage
The standard requires a voltage measurement when the unit is actually delivering a meaningful signal into a real loop. Not specified as peak to peak, instantaneous, or measured at low loads or with continuous sinewave signals as is sometimes the case today. - Area coverage
IEC 62489-1 includes a way to state area coverage for an area or perimeter loop, for 1:1 and 3:1 aspect ratio rooms. While area coverage is a very complex affair, and values in reality will be much lower in the presence of metal structures using MultiLoop™ solutions, the reference method does make for a fair comparison between equipment.
The important characteristics for a hearing loop driver as defined by IEC 62489-1 are shown in the article below.
Ampetronic™ hearing loop systems help to safeguard the rights of people who experience hearing loss.
For more information see the article mentioned, call Ampetronic on +44 (0) 1636 610062 or email sales@ampetronic.com