The lab, Meta says, is “dedicated to advancing audio technologies for Meta’s future AR and AI glasses,” and includes anechoic chambers for near-silent testing, a configurable reverberation room, which can mimic many different sound environments, and a 3,600 square foot area with sub-millimetre optical tracking to improve context-aware audio features.
However, the form factor clearly presents specific technical challenges. Currently, full noise canceling is a luxury that Ray-Ban Meta wearers must go without, as it’s an open-ear speaker set up for the glasses. There is an on-device five-mic array, which works with AI to reduce background noise during calls and recordings, plus it recently rolled out its AirPods Pro-style conversation focus feature. But it seems there’s more to come.
Hearvana AI is also doing its own work in this area too. “Now that we’ve actually cracked the code for hearing aids and earbuds,” says Gollakota, “then smartglasses actually makes everything much easier because we have more microphones, there’s more compute and more power budget available.”
Next-Gen Soundproofing
Noise cancellation doesn’t just happen in headphones and smartglasses, of course. Soundproofing is one of the original ways we used to reduce noise in our environment, and it’s getting better all the time. MIT Materials Science and Engineering researcher Grace Yang has experimented with sound-suppressing silk fabrics, containing fibres that vibrate when a voltage is applied, in order to interfere with unwanted noise, and which could be used on walls or room dividers.
More conventional acoustic insulation makers, who manufacture the much thicker soundproofing options, are also increasingly turning to more natural and sustainable materials, such as sustainably grown hemp fibres (BASWA Natural), industrial hemp blended with recycled textile fibres (IndiNature’s IndiSilence) and mineral wool (ROCKwool), all of which are Quiet Mark certified.
And if you simply don’t have the time or the budget to create a soundproof environment at home, in the office or at an event, digital tools from companies such as Krisp and ai-acoustics are popping up to ‘de-noise’ audio recordings after the fact with AI-powered noise cancellation, anti-reverb and audio enhancement tools for meetings.
Perhaps one of the most incredible advancements in this area has come from a close study of nature. Marc Holderied’s bio-inspired meta-material went viral on TikTok in 2023, after he touted its use as “sonic wallpaper.” Holderied, a professor of sensory biology at the University of Bristol, says he doesn’t mind the eccentric academic label but he’s recently switched to an “acoustic wallpaper” descriptor to avoid any connotations with a certain video-game hedgehog. Now, he’s getting down to the serious matter of making it a reality.
Courtesy of Attacus Acoustics
Courtesy of Attacus Acoustics
Holderied’s sound absorber prototypes are based on the unique microscopic scale structures found on moth’s wings, which evolved to counter the high-frequency sounds produced by bats using echolocation in order to hunt. When the sound hits the scale, it vibrates to absorb the specific frequency it is tuned to and with different shapes and sizes of scales across the wings, vibrating at different frequencies, the whole sound is neutralized. “We are approaching the potential application from a position of tens of millions of years of experience, rather than starting from the engineering principles. So our reverse engineering actually gave us a head start,” says Holderied. “The key invention is that they are thinner by about a factor of 10 than existing solutions.”
Wall of Sound
So it’s thin and, according to its inventor, quick, cheap, and scalable too. How does it perform? “What we’re working on is to make this ultra thin and broadband, so the best prototype we have at the moment achieves one over 100,” he explains. “So that means one hundredth of the wavelength being absorbed. We are getting to 70 or 80 percent of energy absorbed and we are currently working on making the absorption coefficient higher into the 90 percent range. That’s what we’re working on; we have the theoretical models that allow us to do this.”
The prototype material can be made transparent—not completely clear, there’s some visible patterning—for use on windows, and it can work behind fabrics or integrated into wood panelling. Holderied and his team are also currently working on research into the nano structures inside the wing’s scales, which hasn’t been published yet. “We find remarkable stuff happening there that also contributes to the acoustic performance.”
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