When designing a pair of noise-canceling headphones like the Sony WH-1000XM5, there are a million considerations to make. For starters, you need to design around sound quality with high-quality drivers and built-in speakers. You need at least one processor to decode the information received via Bluetooth and deal with the complexities of hearing ambient noise and calculating the counterwaves to cancel it out. You’ll need a battery to power everything, obviously, and an app that can talk to headphones.
The Sony WH-1000XM5 has all of these, many of which are among the highest quality we’ve seen on a pair of wireless headphones, perhaps rivaled only by Sony’s previous flagship headphones, the Sony WH-1000XM4, and the Bose QuietComfort 45.
At first glance, it may seem that Sony may have put itself in a corner. By producing a great pair of headphones last year – and again this year – it has – inadvertently – made it difficult to actually innovate on an annual basis.
But how does one become more silent than absolute silence? What happens when you reach the limitations of wireless audio reproduction? These are the problems that Sony now finds itself facing.
How does noise canceling work and why is Sony so good at it?
Noise canceling technology is nothing new and works on a very simple mathematical principle – sound, in the form of waves, has a wavelength and in order to “cancel” the incoming sound, all you have to do is create a second sound wave inverted by 180 degrees to block out unwanted noise.
The effectiveness of a pair of headphones in this lies in how accurately the microphones pick up incoming ambient noise, how fast and how powerful a counter wave is from the headphones and how well the headphones create a seal using the ear to eliminate outgoing or incoming sound leakage.
To make the noise cancellation top-notch, Sony doubled the amount of microphones in the Sony WH-1000XM5 from four to eight and added a dedicated second processor in the form of the Sony V1. Two processors working in tandem help dramatically reduce the amount of audible noise in the mid-range and advanced audio spectrum while keeping low noise like jet engines in place.
This does not mean that the Sony WH-1000XM5 can create complete silence – it cannot. If you wear it outside while mowing the lawn, you’ll still be able to hear the mower at your feet. If you’re wearing it and someone is playing an instrument next to you (say, the ukulele you use to annoy your girlfriend while she’s working), you’ll still be able to hear that instrument on that music.
Sony has not quite arrived pure Silent so far, but in the next few years it will be very close and then, finally, you’ll need to chart a new course for noise-canceling headphones.
Looking to the future
As we get closer to perfect noise cancellation, Sony will have to look elsewhere for innovation, perhaps in better sound reproduction, comfort, utilities, and features. So where does Sony go next? Based on what we’ve seen over the past year, innovation for the company has taken a number of forms.
As for the set of true wireless earbuds, I’ve eliminated noise cancellation completely with Sony LinkBuds. Completely open wireless earbuds allow users to hear what’s going on around them instead of blocking out incoming noise. It’s a different direction from the Sony WF-1000XM4’s noise cancellation, and it’s one of the ways Sony has shown it’s willing to think outside the box.
For spatial audio, Sony has invested some serious money in 360 Reality Audio, a proprietary format created by Sony that is specifically designed to work with compatible Sony amplifiers (such as the Sony SRS-RA5000) and amplifiers such as the Sony HT-A7000.
Spatial audio incorporation appears to be at the top of Sony’s list of future headphones — the new Sony WH-1000XM4 and WH-1000XM5 already support the format — but the increased power and convenience of using 360 Reality Audio are two areas the company can still improve in the future.
Finally, Sony will have to figure out how to push the needle forward in terms of sound quality above wireless standards. A few years ago at CES, Sony unveiled LDAC, a new codec that can significantly increase the amount of data transmitted over Bluetooth. The standard SBC available on all Bluetooth devices supports a maximum bandwidth of 320 kbps, but LDAC – available only on Sony devices – bumps the bandwidth to 990 kbps.
While LDAC has been a huge boon to Sony’s flagship headphones, it still isn’t where CDs are (1411kbps) or anywhere near the 24-bit/192kHz recording limit. With a bit rate of 9216 kbps. LDAC is the starting point for something bigger, but there is clearly more room for growth.
To that end, even though Sony has brought better noise cancellation with each new iteration of its headphones and is nearing its limit on the technology, it still has other areas that could be improved to keep the WH-1000X series king of the castle. For a few more years.