Humans hear space. Because our ears are located on either side of our head, we receive audio signals in each ear at slightly different times depending on our position. This allows us to localize sound with a great deal of accuracy.
So what happens when we close our ears off and listen with earbuds or headphones? According to Dr. Sean Olive, Acoustic Research Fellow at HARMAN, “we tend to localize the sound coming from headphones inside or slightly around our heads.” This can feel less natural than listening to the same audio through speakers, where the sound is externalized and coming from a source in front of us with some reflection around the room. Without that sense of envelopment, headphone listening can be seriously compromised compared to loudspeaker listening.
It’s Dr. Olive’s job to try and remedy this disparity. In the audio products he helps develop, the goal is to create “accurate sound” that feels as close as possible to professional loudspeakers in ideal conditions. For example, HARMAN has worked on a headphone and software system called LiveStage, which uses signal processing to simulate the experience of having a speaker in front with reflections coming from the side. “It essentially uses spatial processing to trick the brain into thinking there are sounds outside of the head,” he explains. He’s also worked on head tracking, which is technology that recreates the experience of natural hearing by noting the angle of your head and electronically adjusting the audio signal for each ear every few milliseconds. Although this type of technology is currently used primarily in virtual and augmented reality, HARMAN has started putting gyroscopes in select headphones so that when such technology is used more widely, the headphones are ready to track head movement with just a software update.
The future of sound seems likely to fully embrace our relationship to space. Dr. Olive believes it will be customized, immersive, and multi-dimensional: “In the future you’ll walk into your living room or wherever you’re listening and there will be a body scan, like you’re in the transporter on Star Trek, and then your audio experience will become completely personalized based on your physiology.” With more and more attention being paid to the individual experience, the future may be here sooner than we might suspect.
HARMAN is a proud sponsor and partner of the Rubin Museum’s exhibition The World Is Sound.