Bench Talk

(Source: Unicorn Trainwreck- stock.adobe.com)

Our love for audio—whether in music, theatre, or gaming—is nothing new. It's driven us from the early days of stereo to advanced surround sound, prompting the development of sophisticated home theatres and premium audio gear.

Yet, the world of audio has always been highly subjective. What's harmonious to one might be jarring to another. The deep thrum of bass exhilarates some of us, while others are captivated by the clarity of trebles. To complicate matters further, a track that sounds perfect with one set of equalizer settings might need adjustments the next time, even for the same listener.

The introduction of surround sound further muddled these waters. As we moved from the 5.1 systems to 7.1 and then 9.1, the sheer number of speakers, woofers, and tweeters seemed to multiply endlessly in our search for auditory perfection. And just as one thought they had mastered their setup, along came revolutionary technologies like Dolby Atmos and DTS, which incorporated dimensions like height into the mix.

Amidst all these advances, spatial audio promises to be a game-changer. Instead of a one-size-fits-all approach, it introduces customized audio experiences. Through detailed 3D scans of a listener's head, a custom audio profile is created. This isn't just about the spacing or shape of one's ears, but about listening sensitivity as well. In-ear microphones detect a listener’s unique Masimo sensitivity. This sensitivity, a reflection of how our ears respond to specific frequencies, is then paired with the anatomical data. The result? An audio stream tailored to provide each individual with an unparalleled, immersive listening experience.

Key to making the spatial audio experience truly immersive is head tracking. As you turn your head in real time, you hear different things coming from different directions. Life is immersive, and spatial audio tries to mimic this—but, there is one problem. In a home theatre environment, how does an audio process engine know where your head is oriented? It doesn't unless you layer even more technology over it. It is possible to have video cameras watching you as you watch a movie to discern what you are hearing as a result of your head’s orientation. It is also possible to strap a cell phone to your head and use its accelerometers and gyros to track your head. Or you could even have everyone in a theater wearing a VR headset with head tracking and spatial audio support (Figure 1).

Figure 1: One solution for head tracking in home theatres using spatial audio is to have everyone wearing an immersive VR headset with accelerometers and gyros built in. (Source: Marija - stock.adobe.com)

Some cell makers are implementing spatial audio processing capabilities into their phones, and operating systems are proponents of this approach. This may work, but not as well as a technology that anchors your head position using accurate data.

Currently, immersive gaming uses this approach to head positioning and utilizes precise data for a more immersive experience. Using a VR headset allows the VR software to know where your head is oriented since the screen is updated to reflect the direction you are looking. Moreover, as you see it, you will also hear from that perspective.

This is why gaming has the potential to drive this technology forward. First, it is more widespread than any other application (so far). In addition, gaming software makers will quickly adopt this technology because gamers are intensely attracted to the more immersive experience. Gaming consoles have the processing horsepower and memory/storage facilities to store a spherical audio track necessary for spatial audio to work.

In the near future, it is possible that in addition to embedding microphones in earbuds, accelerometers will also be embedded into them, along with higher-speed bidirectional wireless communications to allow other markets to take advantage of the spatial audio benefits. These advances will enable those in home theatres to watch a symphony, for example, and as they turn their head, they hear a more pronounced woodwind section, brass section, or string section, depending on where they are looking.

It may also be possible that military infantry will use this technology, coupled with highly advanced and filtered directional audio microphones, to detect enemies in a forest, desert, or other hidden environment. Breathing and heartbeats can be filtered and used as a soldier orients their head to find a target.

As we stand at the brink of an era where audio can be as personalized as a fingerprint, we must also acknowledge the challenges and intricacies accompanying such advancements. Spatial audio, with its promise of hyper-personalization, relies heavily on precise head-tracking, a feature that might necessitate integrating even more sophisticated technology. As gaming continues to lead the charge, being the most widespread application, it sets a precedent for other domains, from home theatres to potential military applications.

While the immediate future may see us sporting VR headsets or earbuds equipped with accelerometers, the broader horizon promises an auditory experience that's not just heard but felt. This next chapter in audio technology will cause us to listen, immerse, adapt, and evolve. Just as sound is boundless, our quest for the ultimate listening experience is too, pushing us forward into new possibilities.