Sound shaped to you: Bose CustomTune technology

By tailoring sound and noise cancellation to the unique shape of each individual’s ears, this technology revolutionizes the way we experience music.

Bose QuietComfort Earbuds II on a wet bench outside

A brainchild of a rocket scientist

In the realm of audio, headphones and earbuds were conventionally crafted to cater to a broad user base. However, this one-size-fits-all approach often fell short of delivering optimal performance. Why? Because every individual’s ears possess unique characteristics, influencing the way sound is perceived and noise is cancelled out.


Recognizing this, John Rule, PhD, an aerospace engineer and senior systems engineer at Bose, proposed an ingenious solution: customize headphones and earbuds to the unique contours of each person’s ears, thereby elevating both sound quality and noise cancellation efficiency.


After half a year of dedicated effort, Rule’s concept of personalized noise cancellation materialized, evolving into what is now known as CustomTune sound calibration technology. This groundbreaking innovation made its debut in Bose’s noise cancelling earbuds, Bose QuietComfort Earbuds II.


How does CustomTune work?

When you first put QuietComfort Earbuds II in your ears, they send out a welcome chime, sort of like a thwomp sound. That chime travels through your ear canals and bounces back to the earbuds, where it’s picked up by microphones. That’s where CustomTune works its magic.

Using some serious math and complex algorithms, it figures out how your ears tweak that chime based on their size, shape, and depth. Each ear has its own way of amplifying some sounds and muffling others. CustomTune steps in to balance things out, aiming to keep the sound as true to the original recording as possible.


And it doesn’t stop there. The noises from the outside world, along with the noise cancelling waves the earbuds send out, also take a little detour through your ear canals. CustomTune catches those changes caused by your ear’s unique shape and makes adjustments. The result? A much quieter experience. It even takes the edge off the trickier sounds to reduce, like voices.

CustomTune revolutionizes the way we experience music

When Rule and the rest of the Bose team put CustomTune to the test, they got quite a surprise. The QuietComfort Earbuds II outperformed every other noise cancelling earbud or over-ear headphone in shutting out the world.


“Why does this matter? Without powerful noise cancellation, you’re forced to turn up the volume so high it becomes uncomfortable to listen,” explains Rule. “QuietComfort Earbuds II remove almost all the outside noise, allowing your music to play into that nice quiet space.”


And here’s where it gets even cooler. When you hear music, it’s like the artist’s creation taking a little journey through your ear canals. Your ears, being unique and all, might emphasize some parts and tone down others.


“This means your music doesn’t sound the way it was mixed and mastered in a studio,” says Rule. “CustomTune removes the distorting effect your ears have on the sound, ensuring your music sounds the way the artist intended it.”


Woman wearing Bose QuietComfort Earbuds II outside

A legacy of innovation at Bose

Reflecting on the discovery of CustomTune, Rule points out that new ideas rarely come out of nowhere. Innovation happens when individuals or teams apply their expertise in one field to solve a problem in another. It took a rocket scientist to invent personalized audio.


“I’ve worked in lots of different research fields, from acoustics and fuel cells to defense technology and high-powered lasers,” says Rule. “The Eureka moment for CustomTune came when I applied a math technique from my aerospace background to this acoustics problem.”


Is there something about Bose that promoted the discovery? Rule says that Bose’s culture of innovation allowed him several months to work on a project with no guarantee of success.


“Amar Bose, the company’s founder, believed the company should always have a team of smart people doing research that isn’t tied to product development. Their goal? To discover better stuff. Later, we can figure out how to turn new discoveries into great products. If you have a great idea at Bose, you’re encouraged to pursue it — and that’s exactly what I did.”


Product availability may vary by country.


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