The story of AirPods actually begins with this iPod.
With Apple’s popular personal music player, the company has shipped its first set of headphones. Sure, they were wired and very basic, but the accessory laid the groundwork for what would eventually become AirPods. EarPods will be on the way Comes with iPhone In 2007 and A 2012 redesign In 2016, it produced something more similar to the first generation of AirPods. The company’s work to improve the fit of the EarPods continues to pay off as Apple prepares to introduce noise cancellation. AirPods 4.
“We started out trying to learn a little bit about human physiology and what shapes fit people’s ears better,” Kate Bergeron, Apple’s VP of Hardware Engineering, told me about those early days. “We started doing some MRI scans and trying to figure out how to collect the data, but we didn’t know how many scans to do or how many different ears we needed.”
Over the years, Apple has developed more efficient ways to collect data, so it can build a database of ear shapes much faster than in the early days of EarPods. Bergeron explained that he expects the company to “continue this journey forever” when it comes to developing new versions of AirPods.
During what Bergeron described as the “dark days of COVID,” a small group from the AirPods team was trying to solve the dilemma. They wanted to bring effective active noise cancellation (ANC) to the open design of “regular” AirPods. The crew had already done this successfully on two models AirPods Pro and continues AirPods Max headphones. But this time, it was important to keep the outdoor nature of the AirPods, while also providing the technology to block out distractions.
So in 2021, within a few days, Bergeron and AirPods marketing director Eric Tresky met in one of Apple’s acoustic labs for a demo. At the time, the team wasn’t sure if there was anything viable, but asked the chief executive’s opinion about it anyway.
“We were just blown away,” Bergeron recalled. “We said we’ve definitely got something here, we’ve got to go after it and we’ve got to make it happen.” The acoustic and computational work required for an efficient ANC algorithm occurred concurrently with iterations to improve fit. Overall comfort for AirPods 4.
After testing the AirPods 4, I can say that the fit and comfort have improved since the third-generation model. But Apple also expanded the capabilities of the headphones with the H2 chip and microphones AirPods Pro 2. This combination of advanced technology allows Apple to continuously monitor the fit to the user’s ear, updating the ANC algorithm in real time so that noise cancellation is effective even when the AirPods are moving.
“It’s even more computationally intensive than AirPods Pro in many ways,” Bergeron said. “The ear tip gives you a pretty snug fit.”
Apple’s journey with ANC began with the development of the first-generation AirPods Pro, which debuted in 2019. Effective active noise cancellation is usually more common in on-ear headphones with a few exceptions, but Apple has realized that it creates a distraction-free listening experience. It was attractive to “pocket” users. Of course, the company will follow up with its own headphones, AirPods Max, before the powerful second-generation AirPods Pro.
Treski explained that the ANC configuration, or what he describes as third-generation Adaptive EQ, constantly controls and adjusts any equalizers for both active noise cancellation and sound quality — and in real time. So, in addition to the redesigned shape, the acoustic architecture of AirPods 4 also plays an important role in providing effective ANC in open headphones.
“It’s really, really hard to create this great ANC quality in a product that doesn’t have an earpiece,” he said. “The power of the H2 allows that, so we’re really doing a lot with the H2 chip to control the ANC quality and listen to the ambient noise from the microphones to make sure we’re canceling as much as possible.”
The lack of an eartip on the AirPods 4 also poses a problem for transparency mode. Treski noted that it’s “arguably more difficult” than mastering ANC on open headphones, since you have to mix the ambient sound from the microphones with what you naturally hear through your untethered ears. There’s a perfect mix that will look real to your brain, but it all has to be done with very low latency so that the automatic adjustments don’t cause any delays coming through the AirPods.
The new shape for AirPods 4 also made it possible to improve the overall sound quality in the headphones. The front end of the buds, which Bergeron calls the team’s “snorkel,” is very different from the AirPods 3. According to him, because the previous model was more open, engineers had more freedom to work. With the new version, the driver had to be adjusted so that it wouldn’t reflect sound to the internal microphone that tracks the noise in your ear. That’s why the drivers are now pointed down your ear canal, and why they’re slightly recessed.
“It required adjusting the driver and the front of the product to get an improved fit,” he said. “The mechanical engineers do the packaging of the whole product, trying to fit everything in. The acoustic engineers say, ‘Okay, given these constraints, this is the best place we can put the driver.'”
The overhaul of the design in AirPods 4 also applies to the case. Apple managed to slim down the accessory while simplifying your interaction with it. The end result is “the same magical experience,” Bergeron noted, but the lack of a button allowed engineers to eliminate overall thickness and rely on the accelerometer. Removing the button also gets rid of a place where liquid could potentially get in, so the case has the same IP54 rating as the new AirPods.
“We’re getting a double win there,” Bergeron said.
