Apple took me into 'one of the quietest rooms anywhere in the world' and now I understand its obsession with AirPods Pro sound quality

Listening to the AirPods Pro 3 for the first time, I wondered aloud how Apple put so much audio space inside those tiny wireless earbuds. I heard bass, mids, highs, lows, and separation that I'd normally expect from over-the-ear headphones. Turns out, though, I'd get my answer a few hours later when I toured Apple's Audio Lab just a few short steps from Steve Jobs Theater.
Unlike its neighbors, the Apple Audio Lab is an unassuming structure just down the road. I would tell you the exact location, but Apple is not in the habit of inviting regular visitors to the lab. Let's just say, it's a warren of spaces, with virtually all of them dedicated to the art of audio perfection.
It's worth starting where my tour began, which was in the foyer with Steve Job's own set of Wilson Audio Grand Slamm speakers, two towering edifices of wood and acoustics. Jobs, unsurprisingly, was a fan of audio and spearheaded the development of Apple's first Audio product, the iPod.
The iPod can be fairly blamed for the creation of Apple's first set of EarPods in 2012, which also shipped with the iPhone 5 – although Apple's basic in-ear "iPod headphones" can be traced back to 2001 (with, you guessed it, the first iPod). But Apple's redesigned EarPods were a direct response to the lackluster audio quality found in other wired earbuds. That effort led to the creation of the first AirPods in 2016, and now these new AirPods Pro 3 wireless buds.
Everything that followed in our tour tied together the various threads that make up the fabric of AirPods Pro 3's existence. From Active Noise Cancellation and Transparency mode to sound quality, hearing aids, and spatial audio, it's all connected to this lab and the work Apple conducts in it.
We were greeted by a group of engineers who took us through rooms and spaces with names like Nocturn and Sound City.
In one of the few spaces where I couldn't take pictures, I saw a completely dismantled AirPods Pro 3 earpiece under glass. Each bud is made up of at least two dozen tiny pieces. I noted that the two largest components (if you could call them "large") were the driver and the battery.
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While the AirPods Pro 3 looks similar to its predecessor, it is a complete redesign, and Apple engineers showed us how they worked to account for and manage every nook and cranny inside each AirPod, or as they described it, "a network of tubes and slits that allow air to move through the product."
To make that big sound while managing the conflicting needs of expelling pressure that might build up during a workout, and the powerful ANC that those same people might want to keep out all sounds, Apple had to manage every microscopic detail. These labs are certainly one way to do it.
We were led through a maze of corridors (I wondered if any of this was inspiration for Apple's Severance) to a hallway of small booths that serve as audio metric measurement spaces.
In one, we saw a medical-grade ear testing system that Apple used to test people's hearing and see if the measurements Apple can now gather with its clinical-grade hearing test system on AirPods Pro match up. For a second, it looked as if I was in an ear doctor's office.
Apple uses these tuning studios as reference points, not just for AirPods Pro but myriad other Apple products. "Every Apple product that makes sound goes through this hallway," they told me. The goal? To anchor the music to what the artists intended when they first created it.
In another space, I saw a variety of studio-grade microphones. The audio capture capabilities of these devices is almost as important as the audio output. In the corner of one space was a geodesic sound sphere mic developed by Apple to help it create the right kind of spatial audio sonic soundscape.
Apple's audio team listens to thousands of hours of music and is composed of audio veterans, people who have mixed audio on Broadway, worked in the recording industry, or spent decades as acoustic engineers.
Sometimes, though, it's silence that defines the quality of sounds. Apple's Audio Lab includes a large anechoic chamber, a space defined by its ability to suppress all sound.
The room is almost like a building within a building in that it's separated by a three or four-foot gap from the rest of the building, and you literally walk over a plank to step inside.
The room is filled with foam wedges that line the walls, ceiling, and floor, a platform that is essentially high-tension chicken wire suspended over the foamy base below. You sort of bounce on it as you walk. Apple described the space as "one of the quietest rooms anywhere in the world."



We all stopped chatting for a moment to listen to the silence, which in itself is almost deafening. To demonstrate the sound-dampening abilities, our host turned his back on us and clapped at the wall, which effectively obscured most of the sound; there was no echo, no sharp retort. A total lack of sounds except for the beating of your heart is an otherworldly and not entirely pleasant experience.
There are many uses for such a room, including identifying unintentional sounds coming from Apple's own products. Apple likes to take them into the space, identify the sounds, and then work to eradicate them. As you might guess, any sonic imperfections impact the quality and fidelity of the audio Apple products are designed to produce.
Having such a space makes the creation of some audio algorithms easier and purifies the process. The room features an arch of speakers with a chair at the center. This is designed to recreate how spatial audio arrives at both your body and ears. It bounces around, and it turns out that we perceive the direction of audio from how the sound hits these spaces and arrives in our ear canals.
To create an algorithm that matches that real-world experience, they measure it against how people perceive the actual spatial audio arriving in the room.


Our final stop featured more soundproofing and a spherical array of speakers with a rotating chair at the center. This "Fantasia room," as it's called, is all about creating fantasy sounds that include rock concerts, airplanes, Apple Stores, and more.
Again, Apple wants people's experience of this spatial audio to match what they get with AirPods Pro 3. I didn't test the assertion against the new ear buds, but at least I had the chance to sit in the chair and spin as a virtual rock concert played around me.
The tour reminded me of Apple's intense need for perfection, or at least to get as close to perfection as any algorithmic recreation can be. Apple uses the brute force and fine-tuning of audio experts, high-technology labs, and physical construction to create every necessary environment, all to engineer a thumb-sized AirPod Pro 3 that is music to your ears.
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A 38-year industry veteran and award-winning journalist, Lance has covered technology since PCs were the size of suitcases and “on line” meant “waiting.” He’s a former Lifewire Editor-in-Chief, Mashable Editor-in-Chief, and, before that, Editor in Chief of PCMag.com and Senior Vice President of Content for Ziff Davis, Inc. He also wrote a popular, weekly tech column for Medium called The Upgrade.
Lance Ulanoff makes frequent appearances on national, international, and local news programs including Live with Kelly and Mark, the Today Show, Good Morning America, CNBC, CNN, and the BBC.
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