Skip to main content

Here’s how Apple’s HomePod can hear you across that noisy room

Apple Homepod
Rich Shibley/Digital Trends

Ever wonder how the Apple HomePod is able to hear you say, “Hey Siri” from across a noisy room? It took a lot of very smart people to make that happen.

A new post on Apple’s machine learning blog details all the thought and technology — both hardware and software — behind the marshmallow-shaped speaker’s ability to hang on your every word. The challenges, it turns out, were pretty immense.

“The typical audio environment for HomePod has many challenges — echo, reverberation, and noise,” Apple explains. “Unlike Siri on iPhone, which operates close to the user’s mouth, Siri on HomePod must work well in a far-field setting. Users want to invoke Siri from many locations, like the couch or the kitchen, without regard to where HomePod sits.”

Get your weekly teardown of the tech behind PC gaming
Check your inbox!

To deal with these problems, the team used a mixture of what it calls “supervised deep learning” and “unsupervised online learning” to determine how to interpret the signals from its multiple onboard microphones. Essentially, the speaker is able to use this machine learning algorithm to determine which is the optimal audio stream for listening at any given moment, allowing it to always have a keen ear out for where it might be hearing, “Hey Siri.”

There is a heap of cool software that allows the speaker to optimize speech detection and tune out things like music, environmental sounds, and other non-speech audio. But even when it is focused on speech, there are other challenges.

“Far-field speech recognition becomes more challenging when another active talker, like a person or a TV, is present in the same room with the target talker,” reads the post. “In this scenario, voice trigger detection, speech decoding, and endpointing can be substantially degraded if the voice command isn’t separated from the interfering speech components.”

The team developed a unique formula for dealing with this issue — the actual formula can be found on the company’s website — and even developed special ways of dealing with echo cancellation and suppression.

The fact that so much thought went in to creating a product like the HomePod and making it actually work isn’t all that surprising, but being able to hear exactly what the challenges were and how they were solved straight from Apple — one of the most secretive companies on Earth — is refreshing. We recommend you check out the full blog post for more information.

While you’re at it, be sure to check out our list of the best smart speakers if you’re in the market.

Editors' Recommendations

Parker Hall
Former Digital Trends Contributor
Parker Hall is a writer and musician from Portland, OR. He is a graduate of the Oberlin Conservatory of Music in Oberlin…
Apple has upgraded the AirPods Pro with lossless audio, sort of
Apple AirPods Pro with USB-C.

Amid the slew of new Apple products launched today, only the tiniest mention was made of the fact that Apple has also given the AirPods Pro Gen 2 wireless earbuds a not-so-minor refresh. Along with the expected addition of USB-C, making the AirPods Pro the first Apple headphones to ditch the Lightning connector, Apple has also given the iconic white noise-canceling earbuds the ability to do lossless audio wirelessly -- something that has never been seen on the AirPods family before, and is even a rarity among non-Apple wireless audio devices.

There is, however, a catch. The "groundbreaking wireless audio protocol" that allows for lossless audio at 20-bit/48 kHz (a better-than-CD-quality resolution) is powered by the AirPods Pro's H2 chip, but for now, it only works when paired with the upcoming Apple Vision Pro headset. At the moment, Qualcomm's aptX Lossless Bluetooth codec (when used with compatible wireless headphones and smartphones) is the only technology that supports lossless audio wirelessly, and even that technology is limited to 16-bit/48kHz.

Read more
Are Apple AirPods waterproof? Everything you need to know
AirPods 3 on an athlete.

So, you just bought yourself a nice new pair of AirPods, or you're thinking about it because they're among the best wireless earbuds you can buy, and you're wondering if they're waterproof. The answer is no, AirPods are not waterproof and you should not wear them while swimming or in the shower or during a water balloon fight. But, if the pair of AirPods you've got (or got your eye on) is either the third-generation AirPods or the first or second-generation AirPods Pro, then you're in luck as they are water resistant.

We're going to get into what all that means and break down how water resistant each AirPods model is and what their water-resistance ratings mean for your daily activities. Let's go.
Water resistant vs. waterproof
As we mentioned above, none of Apple's AirPods -- AirPods, AirPods Pro, or AirPod Max -- are waterproof. But what is "waterproof" anyway? From an electronic device standpoint, being waterproof means that the device is watertight and can be completely submerged in water. There's a common ratings system designed for electronics to measure this (as well as dust and dirt resistance) known as the IP (Ingress Protection) rating, which we cover in our post on the water-resistance rating system.

Read more
What is NFC? How it works and what you can do with it
NFC settings on an Android phone.

Nearly all of today’s smartphones and smartwatches are equipped with NFC technology. Whether you realize it or not, your phone's NFC scanner is likely active right now. Don’t worry, though, as the NFC chip in your phone is a passive scanner that does nothing until you hold it within a couple of inches of another NFC device or tag. Like many features of your smartphone, it quietly sits in the background until it's needed, but it can also be used to unlock a wide range of cool features that can make your life easier. If you've ever used Apple Pay, Google Pay, or Samsung Pay, then you've already taken advantage of the NFC feature on your phone. However, NFC can do a lot more than just handle mobile payments. Here's the low-down on all things NFC.
What is NFC, and how does it work?

NFC, which is short for near-field communication, is a technology that allows devices like phones and smartwatches to exchange small bits of data with other devices and read NFC-equipped cards over relatively short distances. The technology behind NFC is very similar to radio-frequency identification (RFID) commonly used in the security cards and keychain fobs that you likely already use to get into your office or gym. In fact, NFC is an evolution of RFID that offers more advanced features and better security, but the two technologies still share a lot of things in common.

Read more