Skip to main content

Active Noise-Canceling

In this episode - Active Noise-Canceling . . .

During a recent flight, with a baby wailing, I realized I had forgotten my noise-canceling headphones and wondered how they work. Have you noticed the constant background roar of jet engines during a flight? Probably not if someone was trying to comfort a squalling baby in front or behind you.

Anyway, noise reduction headphones, also known as Active Noise-Canceling (ANC) headphones, use advanced technology to reduce or eliminate unwanted ambient sounds. Using hardware and software components to counteract external noise and provide a more immersive listening experience and a quiet environment.

Here's a simplified overview of how noise-reduction headphones work:

  • Microphones: ANC headphones are equipped with one or more built-in microphones. These microphones capture the surrounding sounds and convert them into electrical signals.
  • Noise analysis: The electrical signals from the microphones are analyzed by the headphone's internal circuitry. The goal is to identify the frequency and amplitude of the ambient noise.
  • Reverse sound wave generation: Once the noise is analyzed, the ANC system generates a sound wave in the opposite phase to the ambient noise. This reverse sound wave is known as an anti-noise or anti-phase wave.
  • Combining sound waves: The anti-noise wave is combined with the original ambient noise wave. When the two waves meet, they interfere with each other in such a way that they cancel out or significantly reduce the overall sound level.
  • Output to the listener: The resulting sound, with reduced ambient noise, is output to the listener through the headphones' speakers. This allows the user to enjoy their audio content or eliminate the jet engine sounds, allowing them to sleep.

It's important to note that noise-canceling headphones work best for blocking constant, low-frequency sounds like engine noise, airplane cabin noise, or air conditioning hum. They may be less effective against sudden or irregular sounds, such as human voices or high-pitched noises. 

Additionally, the effectiveness and performance of noise-canceling headphones depend on the quality of the ANC technology, the number and placement of microphones, and the overall design. Although different manufacturers may use slightly different approaches to achieve noise reduction, most ANC headphones operate on similar principles.

So my next question was, “Who invented active noise-canceling (ANC) headphones?”

Active noise-canceling (ANC) technology for headphones was developed by a team of engineers led by Dr. Amar Bose, the founder of Bose Corporation. In the late 1970s, Dr. Bose was on a flight and noticed the significant amount of noise generated by the aircraft engines. This inspired him to explore ways to reduce unwanted noise and improve the audio experience for listeners.

Dr. Bose and his team conducted extensive research and experimentation to develop the first practical active noise-canceling headphones. They filed a patent application for their invention in 1978, which was later granted in 1986 (US Patent No. 4,545,982). The patented technology outlined uses multiple microphones, phase inversion, and electronic circuitry to cancel out ambient noise.

Bose Corporation introduced its first consumer ANC headphones, the Bose QuietComfort series, in 2000. These headphones gained popularity for significantly reducing background noise and providing a more immersive audio experience. Since then, ANC technology has become increasingly widespread, and many companies have developed versions of noise-canceling headphones based on the principles established by Dr. Bose and his team.

When flying, remember to pack your ANC headphones. As a side note, you can purchase headphones from vending machines after passing airport security if you forget yours.

I'm Patrick Ball; thanks for listening. See you in the next episode.

Comments

Most Popular of All Time

Beyond Facts-The Deep Dive

✨ In this episode, Beyond Facts: Reimagining School–in the Age of AI . . .   This week's podcast is a bit different; it's another example of how Artificial Intelligence (AI) can offer tools to creatively enhance your analytical presentation of information. We took this week's blog and copied it into Gemini with the question, “If a story is to work, it must, on some level, create an illusion of escape and also achieve a goal simultaneously. Does this apply to my blog post that follows?” What's created is not just an analysis of the writing, but an AI-generated discussion produced “On the Fly” - Enjoy! Did you know that the word "school" comes from the ancient Greek word scholÄ“ , which originally meant "leisure"? Not a rigid schedule or droning lectures filled with "facts," but free time for thinking and conversation. To the Greeks, learning happened best when life slowed down—when you had room to reflect, to ask questions, and to wrestle ...

Retirement Talk

In this episode, Patrick & Huck: Retirement Talk . . .   We all get caught daydreaming sometimes, don’t we? Just like Tom Sawyer or Huck Finn might’ve done, lazyin’ by the river with a fishing pole in hand and the BIG wide world spinn’ in their heads. This morning, with coffee steaming and plans bubbling, I found myself driftin’ into a chat with none other than my imaginary friend–Huck Finn himself. Patrick: “Mornin’, Huck. Say, I’m mighty curious what you’d make of this retirement business.” Huck: “Well now, sit tight, ‘cause I’ve been thinkin’ on that too. Only thirty-one days 'til you're sixty-nine — whew! You're talkin’ ‘bout quittin’, hangin’ up your spurs, Givin’ the workin’ life its final good slurs. Ain’t got no debts, no mortgage, no fuss, Just clean livin’ and freedom waitin’ on the bus. Most folks’d throw hats in the air, cheerin’ loud and proud, But you? You’re starin’ out yonder, lost in some cloud. You're dreamin’ of cyclin' and books and guitar...

The Summer Surprise

In this special episode, The Summer Surprise . . .   Well, howdy there! It's me, Huck Finn, and lemme tell ya, somethin' special happened just the other day. We called it "The Summer Surprise.” Phew-wee! That ol' post box, it coughed up somethin' good! Wasn't no bills, nor them pesky ads, and thankfully, no regular ol' rocks neither. Nope, this here was a letter, folded up neat as a pin, looked a bit like one o' them school lockers, just sittin' there waitin' to be opened. It was from young Sierra, a mighty fine friend, and she'd gone and made some pure, honest-to-goodness artwork with her own two hands. My fingers they was all thumbs, just itching to see what kind of wild wonder she'd whipped up this time. I unfolded that paper, careful-like, you know, and bless my bare feet, there it was! A picture of a whole gymnasium and a mini-soccer field, all done up in colors that just popped. She'd used crayons and pencils, and you could tel...

Drifting with Purpose

In this episode,  Drifting with Purpose: What Huck Finn Teaches Us About Finding Your ‘Why’ . . .  Have you ever re-read a book and felt like it had changed while you weren’t looking? That’s exactly how it feels diving back into Mark Twain’s The Adventures of Huckleberry Finn . I’ll admit, I didn’t expect to be swept away again . It had been decades since I first met Huck and Jim. But here I am – older, hopefully wiser – and finding their journey down the Mississippi more powerful and more relevant than ever. This isn’t just another dusty classic. Twain's masterpiece is a living, breathing story – one that speaks through laughter, danger, awkward truth, and uncomfortable beauty. It’s a book that dares you to ask: “What kind of person am I willing to be?” Right now, I’m deep into Huck and Jim’s incredible journey, and what’s striking me the most isn’t just the plot or the river—it’s the voice. Twain’s masterful use of local dialect pulls you straight into the 19th-century Amer...