A New App Brings Birdsong Back to People With High-Frequency Hearing Loss

Lang Elliott didn’t realize the birdsong he missed until the Worm-Eating Warbler incident. In the 1970s, a professor noticed the bird, but even when standing beneath it, Elliott couldn’t pick out its lusty, high-pitched vibrations. “I watch him throw his head back and open his beak and sing his heart out. And I still don’t hear that bird,” he recalls. This “ear-opener” led to an experiment: Elliott slowed down the speed—and lowered the pitch—of a recording he took in a forest. He was shocked at the birds he heard.

A test revealed that Elliott, then 27, had high-frequency hearing loss, a condition caused by loud noises or aging that one study found can affect nearly a third of American adults under 70. “I missed this huge part of the world of birdsong. , not to mention insects,” he says, a crushing realization for the budding wildlife ecologist. The severity of his hearing loss above a certain frequency – if resulting from a childhood accident with firecrackers, he realized – meant that conventional hearing aids, which amplify sounds, would not help. Frustrated by his options, Elliott turned his dismay into a decade-long journey of developing tools that help birders to recover bird soundscapes.

First Elliott and electronic music pioneer Harald Bode adapted a commercial pitch shifting machine from the music industry. Along with a handmade headset equipped with microphones and headphones to transmit 3D sound, he was able to sense the location and distance of a bird’s voice. But after dragging the setup—design for stugod, not forests—around for a while, he wanted a more portable device. By this time he had taken up a uneanticipated career of traveling the world capturing sounds of birds and other wildlife, which he would eventually license to field guides, museums and movies. He also thought that others could benefit from his efforts.

Enter the SongFinder, a boxy but mobile machine and dual-microphone headphones, which Elliott and electrical engineer Herb Susmann debuted in 1991 for $750. By 2018, when production ended, it was pocket-sized and gained a small but dedicated user base. Laura Erickson, 71, a user for more than a decade, found it “a game changer” for helping her enjoy her beloved LeConte’s Sparrows. A recent user, Jody Enck, 63, says the device “improved my quality of life and my income” because it allowed the environmental consultant to continue conducting bird surveys.

Now Elliott, 74, is releasing his latest iteration of the technology: a free iPhone app, Hear Birds Again, a labor of love developed with programmer Harold Mills. Like SongFinder, its algorithms instantly shift higher-pitched wildlife to frequencies low enough to be detected by people who still hear most human speech and some birdsong, like a robin, but which struggles above about 3 kilohertz. App users can adjust settings to suit their needs – lower the pitch at different intervals to, for example, a Brown creeper, Blackburneror Northern Parula as needed. To help birders truly experience the immersive “nirvana” of birdsong in stereo, Elliott designed another custom headset, equipped with microphones connected to an iPhone and headphones that deliver high-quality, spatially oriented sound without interfering with other audience.

“Looks a bit geeky, but it works,” he says. The headset costs about $170 with shipping, through a partnership between his nonprofit and a British online retailer. Some assembly is required, or users can build their own DIY setup.

Of course, pitch-shifted birdsong doesn’t sound exactly the same, but the pattern remains. “A Parula Warbler going sea-UP still going sea-UP,” says Elliott. He hopes that with practice, users can relearn how to bird by ear, which can be tranceformation. Erickson, for example, found success with SongFinder along with the expensive digital hearing aids that her audiologist programmed to recognize birds, voices, and other sounds above a certain frequency. “These birds become old friends, and it’s so sad to lose their voices,” she says. “When you get them back, even if they sound a little different—well, I look a lot different than I did in my 20s.”

The world of birdsong may soon open up further. In August, the FDA legalized over-the-counter hearing aids, a move expected to accelerate lower-cost devices for those with mild to moderate hearing loss and spur innovation opportunities, for bird watchers and many others. And with the Hear Birds Again iPhone app’s release this month, Elliott is ready to pass the baton. The open-source code, available on Github, allows programmers to create an Android version — or take advantage of whatever technology emerges following.

This story originally appeared in the Winter 2022 issue as “Songs from Silence”. To receive our print magazine, become a member by making a donation today.