When you’re driving a car, you have a speedometer that tells you exactly how fast you’re going. You also have road signs that tell you how fast you should be going. You can compare the two and adjust your speed to match the safe speed indicated by the road sign.
Now imagine your speedometer is broken. How do you know how fast to go? You might try to keep up with those around you and unwittingly go too fast. Or maybe you’ll get a little lead-footed when you hit the open road. There’s no denying that fast is fun.
Loudness is fun too. But we currently drive without speedometers when it comes to enjoying sound.
You can put up as many posters as you want to telling people how long they can listen to a certain volume, but how many have any idea how loud the sound they’re listening to really is? At least an experienced driver might have some idea what moving at 100 km/h might look like. How many people know what 80 dB SPL feels like?
When we hear “turn down the volume,” that’s about the same as only having highway signs that say “slow down.” You could be driving 140 km/h, slow down to 130 km/h, and not really be a whole lot safer. Or maybe you’re only doing 90 km/h, slow down to 80 km/h. You were safe already, but now you’re just enjoying the experience less.
What about bringing attention to the possible consequences of excessive noise? Some have tried to use images of hearing aids to discourage young people from listening to music with positive results (if your idea of positive is stigmatizing hearing aids further). What would the equivalent be in our driving metaphor? Billboards full of photos of crashes and ambulances? Maybe that’d change behaviour a bit, but it still doesn’t offer any gauge of how fast you’re currently driving.
A different approach is using devices that limit volume. Just as a car might have a governor that limits its max speed, you can also purchase headphones with a limit on their maximum volume. However, there’s nothing stopping a person from swapping out their current car, or pair of headphones, for one with a higher top end.
Some devices, such as Samsung Galaxy smartphones, offer a “soft-governor” approach. This appears as a warning when you turn the volume above a certain level. I think this helps, but its still far from perfect. I’m not sure a warning light on my dash would do much to slow me down.
There’s no replacement to a speedometer in a car, just as there’s no replacement to actually measuring the level of sounds that might be damaging. In open spaces, such as concerts and sporting events, this shouldn’t be too hard. There are a tonne of sound level meter mobile apps that can do this. In theory, if you know how loud your surroundings are, and you know how well your earplugs attenuate sound, you can easily figure out how long you’ll be safe for. However, there area couple of hiccups here. These sound level apps are often inaccurate, and your ratings can vary between apps and devices. As well, the ear plug attenuation level is usually a best-case scenario. Few people properly insert earplugs consistently.
The problem gets more complex when looking at headphone use. The volume registered on a sound level meter on your phone is very different than the actual sound level when all that sound is focussed in your ear canal. I’ve maxed out my headphones and held them against my phone’s mic and the sound level app I was using told me the level was fine, but the loudness of these headphones in my ears indicated otherwise. The opposite can happen too. You might have your volume very high, but because of poor-fitting devices, some of the sound might leak out.
In a clinical or research setting, accurate real-time sound level measurements are done with sophisticated measuring equipment like probe tubes and standardized 2 cc couplers. Is there a way to bring this to everyday use? I don’t know. I have some ideas, but I’m not sure how feasible they are. Maybe the solution lies in the hands of those designing and building the next generation of hearable technology. For example, what if Apple’s next generation of Air Pods featured integrated microphones that told your phone in real time how much sound your ears are being subjected to?
(I apologize if my title, a bad reference to an outdated song, offended your sensibilities. It offended mine too.)