Mathematical formula opens up a world of sound

A mathematical formula’s ability to make a world of difference to the hearing impaired has won the Cooperative Research Centre Association’s Inaugural Collaboration Award.

 The formula, known as NAL-NL2, was developed collaboratively through the HEARing CRC and its Core Partner National Acoustic Laboratories (NAL, the research division of Australian Hearing), for inclusion in hearing aid fitting software used by hearing health professionals.

 Its inclusion has given hearing health professionals the ability to better match a hearing aid to the needs of the wearer resulting in enhanced speech intelligibility and improved loudness in a variety of different listening situations.

 NAL-NL2’s ability to provide highly effective hearing aid ‘prescriptions’ combined with Siemens’ vision of incorporating the algorithm into their fitting software has seen it become one of two international ‘fitting’ standards in audiology clinics since its release in 2010.

 According to a 2005 World Health Organisation study, there are millions of hearing aid users (roughly 28 million people worldwide), each requiring a unique pattern of sound manipulation that is ‘prescribed’ for their hearing loss. Poorly configured prescriptions distort signals and create unacceptably loud sounds in hearing aids – decreasing their communication benefits.

 NAL Director Adjunct Prof. Harvey Dillon who played an instrumental role in the development of the NAL-NL2 prescription formula, as well as its predecessor NAL-NL1, said NAL-NL2 incorporates more extensive data on how much information hearing-impaired people can extract from speech at different levels and in different frequency ranges. 

 “It uses more sophisticated methods of predicting speech intelligibility and loudness for people with different degrees and configurations of hearing loss. The final formula, which brings all the data together, is even more sophisticated and is based on neural network mathematics,” Adjunct Prof. Dillon explained.

 Robert Cowan, HEARing CRC CEO said, “we’re delighted that our innovation has been recognised by the Cooperative Research Centres Inaugural Award for Excellence in Collaboration for our work on NAL-NL2.”

 “Our National Acoustic Laboratories staff came up with a brilliant formula for prescribing hearing aids and Siemens provided invaluable input into how it should be best packaged for use in the commercial manufacture’s software. It’s a text book example of collaboration for the translation of technology from a research lab to a clinical environment which is ultimately improving the lives of hearing impaired people around the world. ”

 For further information contact: Greg Lawrence, HEARnet & Media Manager

e: glawrence@hearingcrc.org, t: (03) 9035 5351, mob: 0431 426623.