As we age, our hearing slowly but surely slips away. Time turns down the decibels.

But what, exactly, does that aging-of-the-ears sound like? What would it sound like to go, in an instant, from the hearing of a 20-year-old to the hearing of a 90-year-old?

In the vocabulary of frequencies and decibels, _what does normal hearing loss sound like?_

After finding a set of hearing data available online,1 we decided to develop a small web-based simulator to help you experience, in realtime, the results of natural hearing loss.

How does it work?

Select one or more emoji sound sources.

Drag the slider from the left to the right to increase your age.

The effect is, from year to year, subtle. But from decade to decade, it can be quite dramatic.

What’s important is that the sound does not change in a simple way; this is no standard volume fader. The frequency balance of your ears — the way they respond to high-pitched sounds, low sounds, and everything in between — is all modeled in the “Age” slider.

Aging has the most drastic effect on high-frequency, treble sounds. As these high frequencies are reduced, sounds lose their clarity and take on a more muffled, almost underwater-sounding, timbre.

N.B. The simulator uses the somewhat experimental Web Audio API. If the interactive simulator doesn’t work for you, here’s a [screencast](https://youtu.be/VAJ8dyyO7LU) of the simulator in action.

What if I’m not 20 years old?

Good question. We’re not 20 either. But in a lot of ways that doesn’t matter. If you’re 65 years old and you drag the slider from 20 to 65, you can still experience in real time what you’ve lost in those intervening years (relatively speaking).

Of course, your own exact hearing loss depends greatly on your lifestyle. If you’ve spent your life in a factory or on airplanes or in a rock band, most likely your hearing loss is more advanced than the 50th percentile Swedes whose ears were tested for the data set used here.

Isn’t this kind of depressing? Why would you build this?

We decided to build this simply to satisfy our curiosity. We are a creative audio DSP company, meaning the end result of our work is almost always an ear. And as audio professionals, we’ll continue to rely on our ears for our whole careers. Being able to hear for ourselves what age-related hearing loss sounds like helped us appreciate our ears a little more and better empathize with those who do have significant hearing loss. #availableforconsulting

But when we started building this tool and thinking more about hearing loss, we also started to ask ourselves other questions, like:

Why don’t music-listening programs — like iTunes or Spotify — make it easier for people to compensate for these hearing losses when casually listening to music?

A lot of noise exposure in our world is the result of loud transportation: planes, trains, automobiles, etc. Should there be more focus on making transportation quieter?

Should movies theaters have multiple screenings for different hearing thresholds?

Should audio hardware do a better job of protecting us from loud, potentially damaging, sounds?

Is there anything I can do to minimize hearing loss?

Yes! Definitely.

  • Get some ear plugs & use them often. For musicians, or people who make a living with their ears, it’s pretty easy to justify a pair of custom ear plugs, which sound much better than standard foam earplugs. That said, foam ear plugs also do a great job of reducing noise exposure and are nice when you just want to block out sounds altogether.
  • Don’t listen to music too loud for extended periods of time. Loud sound combined with a long exposure time is a recipe for hearing damage. Take ear breaks if you need to listen to something loud, and try to limit the length of exposure. How loud is too loud? The consensus is that sounds above ~85 dB SPL can cause damage.
  • Watch your headphone volume when listening in loud places. Excessive background noise is one reason that people often crank up the volume (e.g. you’re on a loud airplane and can’t hear the in-flight movie). The louder the background noise, the louder the volume needs to be to achieve the same level of clarity and definition (i.e. signal-to-noise ratio). So, get some headphones (or in-ear monitors) that reduce background noise if you plan to use them in a noisy environment. If you’re a mixing or mastering engineer, reducing the background noise in the studio control room itself goes a long way toward safe listening levels.
  • Hope for medical restoration. Though not yet available to the general public, there is some indication that human hearing loss may be treatable with something like gene therapy or stem cell transplants.

Why does it say “Powered by Dolby”?

Update: We’ve added support for Dolby’s new digital audio delivery format, Dolby Digital Plus. The DD+ decoder has dynamic range modes for several common reference levels (in LKFS), which is becoming increasingly important optimizing the listening experience in different, potentially noisy, environments. Better control of the dynamic range can mean safer listening levels and ultimately less hearing loss.

What are the sounds I’m hearing?

  • 🎹 is a loop from Vulfpeck’s “Wait for the Moment”; pay particular attention to the way the hi-hat starts to disappear in your 60s.
  • 🐸 is a snippet from “Voice of Acris Grylls Dorsalis” from the Smithsonian’s _Sounds of North American Frogs_. Though the voice remains intelligible as you age, the frog does not.
  • 🐦 is a field recording of pre-dawn sounds on a farm near Campinas, Brazil, October 2014.
  • 🚆 is a field recording of announcements in a Cologne train station, April 2010. Easy to imagine how hard it is to navigate a train station when the announcements are so heavily reverberated and the loudspeakers only reproduce a narrow frequency range.

How does it work, technically speaking?

The hearing loss simulator is a small Javascript application that leverages the Web Audio API — specifically the API’s ConvolverNode — to modify the signal. The audio samples are convolved (in real time) with minimum phase FIR filter coefficients that correspond to the current age. The FIR filter coefficients were pre-rendered in MATLAB for each decade and are interpolated on the fly as the “Age” slider is changed.

— Goodhertz, Inc.
Footnotes
1Hearing threshold levels were obtained from a 2003 study of otologically unscreened female and male subjects from ages 19-81 years in Sweden. We used an average of 50th percentile levels for males & females, normalized to age 20. Hearing thresholds were extrapolated to predict the hearing loss that could be expected for subjects older than 81 years.