The wireless, noise-cancelling PX headphones are a first for the company, and as you'd expect, there's some decent tech tucked away inside the ear cups. Noise cancellation is provided by a hybrid feedforward and feedback mic solution. This approach suppresses noise across a broader range of frequencies and with fewer errors than either system can achieve alone. Bluetooth 4.1 with aptX-HD connectivity delivers digitally upscaled, 768kHz streaming audio in 24-bit resolution through 40mm, angled drivers that reach all the way down to 10Hz. The built-in battery purportedly delivers around 22 hours of constant, noise-cancelled playtime on a single charge, while in-built sensors detect whether the headphones are actually on your head or not, stopping and starting your music automatically. Couple this with a dedicated mobile app to control the adaptive noise-cancelling functionality and you have a product that looks to justify the by-no-means inconsequential price tag.
There's no doubt the PXs are a classy looking pair of headphones with some nice design touches. The braided cables are fed out through the lower, concave portion of the headband, keeping them out of harm's way. Slim, low-key buttons on the right ear cup control playback and volume as well as Bluetooth pairing and noise cancellation. Oddly, the ear cups themselves only fold outwards, though in practice this ends up not being a huge problem as the plush, padded carry case fits them perfectly. The two available colours are a matter of taste—my review model came in a shade of gold with dark blue trim, which I found came down on just the wrong side of tacky. The space grey version does smart and understated much better.
Connecting the PXs to your computer or smart phone is a painless procedure. Upon startup, they're set straight into Bluetooth pairing mode, with the indicator light on the right ear cup changing from a flashing to steady blue once successfully connected. You can add other devices by holding the power/Bluetooth button. The indicator light also shows how much charge is left in the battery by flashing green at decreasing intervals as it drains, switching to yellow once it reaches 30% and red at 10%. Usefully, the proximity sensors can tell when the headphones aren't on your head and automatically switch to stand-by mode to preserve battery life.
The free B&W PX Headphone app is simple but well designed. Its main function is to switch between the three Environment Filters that define how comprehensively the noise cancellation works. The three filter modes—Office, City and Flight—offer increasingly enveloping solitude from the outside world. Office allows nearby conversations to filter in while Flight attempts to block out engine and cabin noise. City ends up somewhere in the middle. The aim is to let through enough outside acoustic information for you to safely make your way around town while still providing a space for your music. In practice, Flight mode is the one you'll use the majority of the time. Since I didn't have any air travel booked during the review period, I resorted to spending some time in the company of my washing machine's incredibly loud spin-cycle. The result—drastically reduced outside noise at the cost of noticeably duller sound—was to be expected, and I'm sure that in loud environments you'd be happy to accept a slightly duller top-end if it means enjoying your tunes in a considerably quieter context.
With the noise cancellation switched off, the sound is impressive. The digital upscaling, far from enhancing artefacts and unpleasant frequencies, translates into crisp and tight audio reproduction, presenting an immersive soundstage and impressive stereo-field. The lows punch smoothly right down the centre while the highs dance around pleasingly without getting harsh or overbearing.
While I'd say my ears are an average size, if you run a little bigger in this department, there's a chance the PXs might be just a little too cosy. Even with my ears snuggly tucked inside, they weren't wildly comfortable during prolonged use (we're talking at least two or more hours here). The contact area of the earpads and headband is actually pretty narrow, meaning that over time a noticeable amount of pressure is applied to the sides and top of your head. This isn't an issue for the majority of commutes but you might need to take a break on long flights.
It's clear that Bowers & Wilkins have crammed a lot into these headphones. While the looks won't be for everyone, the construction and materials are as good as it gets. With USB-C charging and a standard 3.5mm jack input, the PX is simultaneously looking both back and forwards in terms of connectivity. The noise cancellation is undoubtedly impressive with an acceptable enough pay-off in terms of audio quality, while the wireless sound is both solid and clear. If you're after some me-time on your next flight or the office ambience is getting just that little bit too much, the PX could be well worth a look.
Ease of use: 4.0
Build quality: 4.5