I have been rather intrigued by a motor vehicle advertisement that's currently in high rotation on television which shows a car warning its driver that a pedestrian has stepped out in front of said vehicle, allowing the driver to apply the brakes and prevent an accident.
I honestly can't remember what type of car it is at the moment that I am writing this, and I am so close to deadline that I won't have the opportunity to watch enough television to see the advert again so I can make a note of the make of the car in time to include it in this editorial... but the fact that I can't remember tells you something about the effectiveness of television advertising, in that not only can't I remember the model of the car, but I can't even remember the make. (Then again, it might just be telling you something about my shot-term memory!)
What intrigued me about the ad is that the person who steps out in front of the car is wearing headphones, the passenger in the car is wearing headphones... and in fact every single person in the commercial is wearing headphones except for the driver... and in my experience as a commuting motorcyclist, most drivers these days are wearing either headphones or earphones as well. I guess that since wearing headphones (or earphones) whilst driving is actually illegal, they wouldn't have been able to get the commercial to air if the driver had been wearing a pair.)
This advert certainly has a ring of truth about it to me, because the large majority of people I see on the street in commercial suburbs — on week-days at least — are wearing headphones. While this is certainly great news for the audio industry (particularly those companies which manufacture headphones, which seems to be all of them these days) it's not so great news for the people wearing those headphones, because many of them will be listening at volume levels that will result in either short-term or permanent damage to their hearing.
And when I say 'many' listeners, I mean around one in every ten.
National Acoustic Laboratories recently measured the headphone playback volume levels most often used by more than 3,500 regular headphone users and found that just over ten percent of them were listening at levels that have been proved to result in hearing damage.
At present, statistics show that around 15 per cent of Australians will experience some form of hearing loss in their life. National Acoustics Labs estimates that as a result of the increase in popularity of using headphones, this figure will increase to 25 per cent by 2050.
Hearing damage isn't only about losing high frequencies, or diminished acuity; it can also mean tinnitus, which causes sufferers to constantly hear ringing or buzzing sounds in their ears for the rest of their life. And like hearing loss itself, tinnitus is incurable.
The take-away here is to ensure that you do not to listen to your headphones at sound pressure levels that could result in hearing damage, which based on current research into hearing loss, means levels of 85dB SPL or more.
But how are you supposed to be able to establish if you're listening to your music at sound pressure levels that are too high?
If you use headphones, a rough and ready method is to load an SPL app onto your mobile phone, and then hold one of your headphones' ear-cups as close as possible to your phone's microphone and measure the volume level using the app.
If you use earbuds, I don't even have a rough and ready method, so you'll need to watch this space, because we're working on a solution for you.
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