Hearing aids have come a long way in terms of design and functionality. One critical component of behind-the-ear (BTE) hearing aids is the tonehook, which serves as a connection between the hearing aid and the tubing of the earmold. While plastic tonehooks have been the traditional choice, ReSound offers an alternative option for their superpower devices – a metal tonehook.
The Advantage of Metal Earhooks
When it comes to superpower hearing aids, metal tonehooks provide an additional advantage over their plastic counterparts – stable gain. Gain refers to the amplification of sound provided by the hearing aid. Metal tonehooks allow for a higher gain, enabling individuals with severe to profound hearing loss to access amplified sound at a louder level.
With the exact same hearing aid Resound Omnia 88 BTE, different power depending on the tonehook.
Plastic Tonehook: 133dB peak Output, Gain of 67dB (power)
Metal Tonehook: 133dB peak Output, Gain of 73dB (high power)
Frequency Bandwidth Considerations
While metal tonehooks offer enhanced gain, there is a trade-off in terms of frequency bandwidth. The frequency bandwidth determines the range of frequencies that a hearing aid can effectively amplify. It is important to consider the impact of tonehook material on the ability to match high-frequency (HF) targets.
When using a metal hook, the frequency bandwidth is slightly narrower compared to a plastic hook. Specifically, if you are aiming to match HF targets above 5kHz, you may encounter challenges achieving precise matching with a metal hook. The difference in bandwidth between the two options is relatively small, typically only a few hundred Hz. However, for clinicians who prioritize precise HF target matching, this consideration becomes relevant.
Individualized Treatment Approach
Hearing aid fittings are highly individualized to meet the unique needs of each patient. Audiologists must consider various factors when determining the appropriate tonehook material for their patients. While metal tonehooks provide stable gain, the choice between metal and plastic should be made based on the specific requirements of the individual’s hearing loss and listening preferences.
For patients who prioritize stable gain and do not have recordable thresholds at or above 5kHz, the metal tonehook can be an excellent choice. However, for individuals who seek a more accurate match of HF targets, the plastic tonehook may be a preferable option.
