December 30, 2020

Waves Nx for earbuds

3D audio in motion

Adam Levenson of Waves Audio teams up with our own Ferdinando Olivieri to explain how true-to-life audio through your earbuds is possible with Waves’ Moving Reference headtracking

December 30, 2020

With your smartphone and your earbuds, you get the freedom to enjoy sound anywhere. But sound on conventional earbuds is inside of your head, not around you like we experience in the real world. Whether you’re sitting in the 10th row center at a concert, or bird watching at a local park, sound surrounds and envelopes you. Natural sound is immersive and that’s the way sound should be. At Qualcomm Technologies, we continuously explore new ways to enrich people’s lives with better mobile experiences, and true-to-life audio is part of that. Waves joined the Qualcomm Platform Solutions Ecosystem program to bring an immersive sound experience to smartphones powered by Qualcomm Snapdragon earbuds* via Waves Nx 3D audio with moving reference headtracking.

Nx virtual acoustics

With Nx, Waves invented a sound reproduction system for headphones and earbuds that uses psychoacoustic science to externalize sound to produce a speaker-like, expansive 3D listening experience. Stereo and 5.1 and 7.1 surround sound are “binaurally rendered,” meaning sound is processed and delivered through two channels into a virtual, precision-tuned listening space. In this space, eight virtual speakers surround the listener and Nx employs filters that model human hearing to activate the perception of sound in 3D. One more vector is needed to fully simulate reality: head movement.

The headtracking x-factor

On conventional earbuds, head movement while listening to music or a movie, for example, results in the whole sound field moving with the listener. This creates a cognitive disconnect that disables our ability to perceive a life-like audio experience. Recognizing the importance of the head movement factor, Waves designed high resolution headtracking into the Nx experience, and with the help of Qualcomm Technologies, brought it to smartphones powered by Snapdragon.

Headtracking is always relative

Nx performs headtracking by using data from a single, embedded sensor called an Inertial Measurement Unit (IMU). On the IMU, tracking is always relative to a directional reference that determines what is forward. From that “heading reference,” Nx can extrapolate the positioning of the eight virtual speakers around the listener’s head. The single sensor design is great for a listener in a fixed position, but if the listener is in motion, like a runner making a turn on a jogging path, the IMU’s heading reference will remain locked even if the listener’s body moves in a new direction.

Nx Moving Reference headtracking

To solve this conundrum, Waves invented and patented a dual-sensor algorithm through which head and body movement is continuously aligned. This technology is called Moving Reference headtracking. When the user is in motion, Moving Reference processes data from both the earbuds IMU and a mobile device IMU to keep the sound field continuously centered and in front of the listener.

Running with Snapdragon

Bringing this experience to smartphones requires a fair amount of computational power, and that power draw may impact battery life. Snapdragon is the solution. Thanks to the Qualcomm Hexagon DSP and its hardware optimizations, Waves Nx runs efficiently on phones powered by Snapdragon, providing an immersive audio experience without the battery life tradeoff.

Nx with Moving Reference is available today

With Moving Reference headtracking, Waves Nx for Android mobile devices on earbuds allows listeners to suspend disbelief and enjoy a lifelike immersive 3D audio experience even while in motion. Technology demos on the latest Snapdragon 855 and Snapdragon 765 platforms are available now and the solution is ready for deployment.

Waves Nx and your smartphone powered by Snapdragon put you in the best seat in the house. And now, the best seat can be anywhere you want to go.