Bowers and Wilkins Pi7 S2 true wireless earbuds

Bowers & Wilkins continues its spate of recent updates to the company’s headphone line with the Pi7 S2 and Pi5 S2 true wireless earbuds, each bringing subtle but significant improvements to a long-standing model. At $299 and $399, respectively, neither new headphone is cheap, and they are clearly aimed at those interested in a high-end experience, look and feel.

For most potential purchasers, the question, of course, is whether they offer enough to make them worth the significant additional cost over the Apple AirPods Pro or the rest of the best true wireless headphones from Sony, Bose and others. We checked out the top-of-the-line Pi7 S2 to find out what Bowers & Wilkins has to offer with this new revision.

A true wireless earbud for audiophiles with a unique transmitter case

The latest update to the company's flagship audiophile earbud appeals to discerning listeners with sound quality improvements and aptX Bluetooth support, plus a cool travel-friendly case that doubles as a transmitter, but given the price, it isn't for everyone.

What we liked about them

The Bowers and Wilkins Pi7 S2 with charging case.

The Pi7 S2 is immediately impressive sonically and otherwise. While the case is substantial (it’s a lot larger than an AirPods Pro charging case, the earbuds themselves are slim and lightweight, and fit securely and comfortably once outfitted with the appropriate ear tip for your lobes. You’ll find tap/touch controls for the usual functions on the headphones; these work as you’d expect, and feel and operate very much like last year’s Pi7.

Once in place, the Pi7 is a predictably great-sounding set of earbuds, with extended lows, smooth mids and plenty of sparkle up top — think an audiophile-friendly sonic signature with a little extra punch on the low end. The dual-driver configuration (a dynamic driver covering the lows and mids, a balanced armature driver handling the highs) is unchanged from the original Pi7, and delivers balanced performance across the audio spectrum.

Everything we threw at it — from N.E.R.D.’s classic banger “Lapdance” to Joni Mitchell’s apocalyptic “Sire of Sorrow” to maestro Daniel Barenboim’s readings of the Scarlatti sonatas — sounded lovely, with rich low end, lots of detail, a clear, stable stereo image and a good sense of acoustic space.

Adaptive noise cancellation is excellent. With a good fit, it reduced environmental sounds (wind noise, our kitchen exhaust fan, a running dryer) to a nonintrusive level. Ambient passthrough was effective as well, letting us stay aware of our surroundings when out for a walk, and to carry on conversations without shouting (once we remembered to turn off the music).

Bowers & Wilkins claims 24-bit performance over the aptX high-quality Bluetooth streaming codec, and while it’s debatable whether this represents “music and movies as they were meant to be heard” (since aptX is still using lossy compression, like every other Bluetooth codec), but it’s one of the few audiophile-approved Bluetooth transmission methods, and there is a devoted audience for better-quality streaming audio. AptX also has less latency than other Bluetooth profiles, so you can potentially get tighter sync with video or games. And the B&Ws offer the latest aptX Adaptive codec, which finds the best balance of latency and quality to optimize for listening conditions.

Does aptX mean better sound? Yes, it does, but it is a minor though perceptible difference most noticeable in a slightly different representation of high-end color. Frankly, they both sound good — just different. And in the environments you’re typically using earbuds, especially when you throw things like noise cancellation into the mix, which changes the response of the Pi7 S2s more than the codec differences do, it’s really a matter of taste, not a night-and-day distinction in quality.

By the way, aptX is not supported on iOS, so for Apple users, the headphones will default to AAC, which provides a perfectly good experience as well despite topping out at a slightly lower bit rate (under the best circumstances, that’s 320 kbps for AAC vs 576 kbps for aptX HD).

The Pi7 S2 has a neat trick up its sleeve that mitigates this somewhat, and may also appeal to the high-end traveler. The Pi7’s charging case doubles as a Bluetooth transmitter. You can use a USB-C cable to connect the case to a computer, letting it function as a wireless DAC, which lets you take advantage of high-quality streaming from a Mac or iPad, for instance.

The Bowers & Wilkins Pi7 S2's charging case doubles as a Bluetooth transmitter, letting you add wireless to devices that don't have it (we imagine the company has in mind the in-flight entertainment systems on some aircraft, but it comes in handy with a lot of older audio gear).

The travel-friendly twist? In the box you’ll find an odd little cable with a USB-C jack on one end and a 3.5mm stereo audio jack (remember those things?) on the other. The idea is that if you want to listen to a device — say an in-flight entertainment system — that doesn’t have Bluetooth, you just plug the case in and you’re all set to use your Pi7 S2s. If you’re set on enjoying the best possible Bluetooth transmission quality from your in-flight source, you’re set.

Just to make things interesting, I hooked the Pi7 S2’s Bluetooth transmitter up to some other devices; since it uses a standard 3.5mm jack you can use it to add Bluetooth audio to any sort of gear you might already own that lacks wireless.

It works well, though as with any Bluetooth transmission you’ll notice a bit of latency (your audio will be ever so slightly out of sync if you’re using the Pi7 S2s to watch a movie on a flight, for instance). It’s not intolerable by any means, but it’ll take a bit of getting used to.

Just for fun, I tried the B&W case with a synth and guitar amplifier (via its line out jack), and in that case I found the latency long enough to be distracting; that’s as expected, and typically Bluetooth transmission introduces enough latency that it’s easy to feel while playing a musical instrument so to find otherwise would be something of a miracle. And as pragmatic reviewers, we’re not too let down by the absence of miracles.

In a more practical application, I then used it with a TV that had no onboard Bluetooth transmitter but did offer AV sync control to compensate for audio delay; in this case I was able to bring everything into reasonable alignment, so in a pinch the B&Ws might be a good way to binge silently every once in a while.

What we didn’t like about them

The Bowers & Wilkins Pi7 S2's charging case is significantly larger and bulkier than the one supplied with the Apple AirPod Pro, and while it does more (including high-quality Bluetooth transmission), it holds a smaller charge.

The main problem facing the Pi7 S2 is the retail price. At $399, it’s double the current street price of the AirPods Pro, which while they don’t support aptX HD streaming or offer as good a cross-platform experience do offer a pretty great experience overall and are more slickly integrated with the overall iOS experience. It’s just a tough act to follow in terms of balancing pleasing sonics with utility.

And if your priority is sound quality, keep in mind that they cost as much as Bowers & Wilkins’ own excellent Px7 S2 over-ear headphones, or the LDAC-enabled Sony WH-1000MX5, both of which offer an even better enthusiast experience if your priority is high-end listening on Android.

The B&W Music app is quite bare-bones, at least in terms of controlling the headphones — it’s a convenient front end for services like Qobuz and Tidal but offers no EQ adjustments. You can manage noise reduction and ambient noise passthrough settings, but that’s about it.

The Bluetooth retransmitter case is a really neat idea, but it has a few downsides, and it’s hard to see overall how it fits into a luxury headphone in a world where most things offer wireless already.

The downside, if you’re using the analog stereo input cable, is that the case can’t transmit and charge at the same time, so if you use it on a long flight you’ll likely arrive with your headphones and charging case drained, so you’ll likely want to pair with a portable battery pack if you’re hitting the road and plan to take advantage of this feature.

Battery life is middle of the road — I got about a half day’s worth of listening from the Pi7 S2 with the adaptive noise cancellation enabled and about an hour longer without. The charging case gives you another 16 hours of reserve, and a 15-minute charge gives you two hours of ANC-free listening. The AirPods Pro will get you a couple of extra hours of listening per full charge, and the case holds almost twice as much reserve.

Bottom line

Like all of Bowers & Wilkins’ recent efforts, the Pi7 S2 is a great-sounding, comfortable and elegant-looking headphone. Android-inclined audiophiles or those who are otherwise looking to eke the last bits of high performance out of Bluetooth will likely appreciate it, and the interesting retransmitter case may be a good fit for Apple users interested in experimenting with aptX or dedicated travelers who are willing to put up with the slight bit of inconvenience.

That said, the Pi7 S2 are not for everyone. Mainstream in-ears like the Apple AirPods Pro don’t give you much worse an experience, and cost around half as much. And for $399, you can get the aptX-capable over-ear Px7 S2, which will be a better overall experience with bigger drivers and longer battery life for extended listening sessions, plus support for aptX (albeit without the cool retransmitter case).