Improving the sound of music with hearing aids
As the soundtrack to our lives, the right song can cause feelings and emotions from an earlier time to come flooding back. From Bruno Mars to Beethoven, the love of music spans generations, whether you’re a serious musician or just someone who just likes singing along to a catchy song in the car. But what if you lost the ability to hear and enjoy your favorite music? For those with hearing aids, that's a common problem.
Many people with hearing aids often give up on listening to music altogether because it doesn’t sound the same, and can, in fact be unpleasant. But a new study indicates there's potential to make music beautiful once again for millions of hearing aid users.
The study, conducted by the University of Leeds and Sheffield Teaching Hospital NHS Foundation, is trying to determine exactly how hearing loss affects the music listening experience. Called “Hearing Aids for Music," the goal is to explore how people use hearing aids in a wide variety of musical situations. Do hearing aids function differently when attending the symphony verses a rock concert? How do they function when listening to music in the home environment or the car? By combining hearing test data with social/psychological data for the first time ever, researchers hope to improve the sound of music for those who use hearing aids.
Researchers hope to use the results of interviews and surveys to identify problems faced by music listeners, and then come up with ways to improve existing hearing aid technology. In turn, this new information could help hearing healthcare professionals to better advise their patients regarding music, and could help hearing aid manufacturers design hearing aids that better meet their customers’ needs.
The problem with hearing aids is that they were designed to amplify speech, not listen to music. They were not made to handle music’s diverse tonal quality and wide dynamic range. Human speech is generally between 30 decibels and 85 decibels, giving it a range of about 50 decibels. Music, however, has a range of about 100 decibels. Hearing aids simply aren’t designed to efficiently process such a wide range of sound.
But individuals who use hearing aids needn’t give up hope. True, some people remove their hearing aids to listen to music, since they find the listening experience so unpleasant with the hearing aids in place. But there are other steps you can take, taking the hearing aid’s design into account.
For starters, modern hearing aids are built with a complex feedback reduction system. High frequency sounds in music, such as flute or piano, for example, will be read by the hearing aid as feedback and the hearing aid will automatically try to reduce or eliminate them. The result? Distortion. By disabling the feedback reduction system while listening to music, the music will sound clearer and more true to itself. You can re-engage the feedback reduction system when you are done listing to music.
Noise reduction systems are another culprit when it comes to altering the way music sounds. Hearing aids are programmed to reduce background noise, necessary to hear conversation in a noisy environment such as a restaurant or party; certain musical sounds, such as sustained chords for example, are mistaken as background noise. Disabling the noise reduction feature will allow your hearing aids to hear all of the elements of your music as music, not noise.
Hearing aids can also be set to amplify an extended range of lower frequencies. For speech, hearing aids need to target high frequency sounds. In music, however, it is the lower frequencies that are the most important.
Luckily, almost any pair of hearing aids can be configured with a “music setting” that disables many of the automatic functions and reduces the amount of processing that needs to occur in the hearing aids. It is important to remember to return the hearing aids to their normal setting when done listening to music.
A study out of the University of Colorado Boulder which took data from 18 hearing aid users suggests that the more processed the music is, whether by the recording studio or by the hearing aid, the more distorted the result. For the study, participants listened to many different music samples from the minimally processed to the highly processed. The results of the study showed that, in general, the less processing that occurs at the hearing aid level, the better the music sounded.
At the hearing aid level, the problem stems from what is referred to as “wide dynamic range compression." A feature that works well for speech, this compression leaves moderately loud sounds untouched but amplifies softer sounds. This setting wreaks havoc on music processing. In addition, a recording technique called compression limiting can cause music to be distorted before it even reaches the hearing aids. The loud and soft sounds are squeezed together in a narrower range, increasing the perceived volume overall. By the time the hearing aid gets its turn to process the music, it has already been through so many layers of processing that distortion is inevitable.
Case in point, in some cases, simpler is better. It turns out less sophisticated hearing aids could be one solution, especially for music that has been heavily processed to change the way it sounds. Newer digital technology, as opposed to older analog technology, converts sound into digits which are then processed by the hearing aids. Music causes the newer hearing aids to be overwhelmed by loud sounds, which in turn causes distortion.
Be sure to ask your hearing healthcare provider which hearing aids will best serve your music listening needs. She can also advise you how to change the settings when necessary, or even design a music program for your existing hearing aids. If you don't have a hearing healthcare professional yet, check out our directory to find one near you.