Hi guys, first post here. I've been lurking for a few years and never created an account, but with the requests for input on these headphones I figured I'd finally create an account and contribute to the community that's taught me so much.
First a little context. I started to get into Hifi audio in the last few years, and don't have the best gear to compare to, but I'll do my best to provide useful information. I run 2 main headphone setups, one for home (open back, less portable) and one for work (closed back, more portable). The home setup is the better of the two... Schiit stack (Modi Multibit + Magni 2 Uber) running either my Sennheiser HD700 or AKG K7XX. The work (and mobile) setup is the one I was looking to replace with the PX, a Dragonfly 1.2 running a pair of Oppo PM-3. I get MUCH more use out of my work setup due to my employment as a software engineer in an open-plan office. I spend ~6-8 hours per work day wearing headphones with music playing.
Full disclosure, I already own other Bowers & Wilkins gear that I absolutely love, so I have some positive bias towards the brand going into this. My home theater setup currently uses a pair of B&W 685 (S2) for left/right with a HTM62 (S2) center channel. This bias led me to test both the Oppo PM-3 and B&W P7 (wired) when I was last looking for headphones. I purchased both to test side-by-side but ended up returning the P7 after a week due to being blown away by the comfort and sound of the PM-3. The P7 was in no way bad, I just liked the PM-3 better.
I bought these headphones with high hopes after waiting some time to pull the trigger on a bluetooth pair. However, I pre-ordered a Pixel 2 XL during the release conference the other day, so with the move away from the 3.5mm jack I figured it's time to see if the world of bluetooth sound can satisfy my requirements. They arrived last night (East coast USA), 2 days after ordering directly from Bowers & Wilkins. I spent all of yesterday evening plus most of this morning testing them. I left them on the charger and running white noise on loop overnight to break them in a bit (I'm still not sure if this is actually required anymore, but it shouldn't hurt). I'll break out my initial reaction below in a few categories.
I almost exclusively listen to Rock/Metal, primarily in the Progressive space, so my testing was done across a range of artists in this area including: Tool, Between the Buried and Me, Dream Theater, Rush, Porcupine Tree, Animals as Leaders, Polyphia, etc. I honestly can't speak too much to how these would sound with Pop/Hip-Hop/whatever's on the radio because I don't listen to it.
Sound 9/10: if you're in this forum this is probably the characteristic you care the most about, and so far, I'm impressed. Having spent the last few years focussed on quality DAC/AMP setups driving a good set of wired headphones I was honestly not expecting anything bluetooth to sound this good. I honestly feared I'd be utilizing B&W's trial policy to send these back. While that's still not off the table, if I do return them it won't be due to sound quality. The soundstage is quite impressive for a closed back headphone, comparable to the Oppo PM-3 I've been using daily for quite a while. Additionally, while I wouldn't say the PX is quite as flat as the PM-3, it's not nearly as V-shaped as the wired P7s or my old ATH-M50x, and overall I find it to be quite appealing for the genres I listen to. The highs are very well defined, and instrument separation is impressive, but the lows are still slightly emphasized to give the bass and drums a little extra kick. The midrange does sound a BIT compressed compared to the PM-3, but I only noticed on a few songs and had to focus hard to pick it out at all. That being said, for obvious reasons these do not compare very well to the soundstage or separation of my Sennheiser HD700, but in all honesty I never expected that due to the closed back/open back difference, not to mention that the HD700s cost a fair bit more and are being driven by a DAC/AMP combo that costs almost what the PX did.
Unfortunately, all of my above statements apply only when noise cancelling is disabled, which leads to the next category
Noise Cancelling 4/10: unfortunately, from my experience so far, the noise cancelling functionality has a rather large, and detrimental, affect on the sound quality. Enabling noise cancelling seems to compress the soundstage to the extreme, making the entire thing sound somewhat muffled and closed in, almost like listening to your music while sitting in a big padded box. It seems to be especially bad at the ends of the spectrum, reducing the clarity of both highs and lows much more than the midrange. This effect seems to scale with the severity of the noise cancelling, with the "flight" mode being much worse than the "office" one. To make matters worse, I'm not sure that the noise cancelling is actually doing much at all. While admittedly this is the first pair of headphones I've ever owned that had this feature at all, I have briefly tested a friend's pair of Bose QC35 and those were on a whole different level. even on the "flight" mode the PX only seemed to be capable of eliminating steady noises like a running fan or refrigerator, while less predictable noise such as voices were just slightly more muffled than they would be with NC disabled. Between the ineffective outer noise suppression and the detrimental effect on the noise quality I truly don't see why anyone would ever enable this feature. Maybe I'd change my mind if I tried them out on a plane, but for any sort of daily use I'd rather take the passive noise isolation provided by the sealed earcups and leave the active cancellation disabled to keep it from mutilating my audio quality.
Build Quality 10/10: I'm not sure what to say here that hasn't been said already. These things feel FANTASTIC. I'm a big fan of the ballistic nylon texturing across the band and earcups, it feels both durable and quality. The whole thing just feels well built... smooth-rotating earcups, no loose connections, you name it, they just feel good. My only "negative" here is more of a design decision than build quality comment. The ear cup rotation feels backwards to me. If you slip these off your head to your neck I'd expect the earcups to rotate such that the padded cups sit against your collarbone, but that's simply not true. instead they've been designed to rotate outwards on offset "arms" such that the metal arms and ballistic nylon cups sit right on the collarbone... not comfortable. Additionally, this way of rotating makes it so that the headphones have their largest footprint when lying flat on a table... not a big deal except that it makes all of the existing hard-sided cases I have obsolete because they want the headphones to lay flat in a compact form.
I'm having a hard time describing this particular issue, but if you look at the images on their site one of them somewhat displays it:
http://www.bowers-wilkins.com/Images/AdminGallery/PX/5-2-px-wireless-headphones-ready-to-travel.jpg
Note that due to the offset point of rotation these would sit MUCH more compact if they rotated the other way so that the ear-cups were facing up in this image. However, they simply won't rotate that direction
Comfort 7/10: If I end up sending these back to B&W this is going to be the primary reason for it. I was honestly hoping these would be more comfortable to wear for extended periods, but so far I'm not thrilled. The main issue here seems to be the clamping force, so I'm really hoping this will improve over time as they break in. However, it's amplified by the second issue... all of the padding feels too stiff, as if priority was put into making everything keep their sculpted shape to maintain the profile rather than making them softer so they conform to the head. This issue applies to both the earcups and headband padding. Once again, hoping this improves with time. I also found my ears heating up and sweating much more often/faster than I find to happen with my PM-3, or the ATH-M50X they replaced. In all honesty this could just be a symptom of my first 2 complaints over comfort. That being said, it's not like these feel like torture devices or would be unwearable for hours at a time, I just find them to be noticeably less comfortable than my current daily drivers.
Other/Features 8/10: For the most part these headphones really hit the feature list I was waiting on. Bluetooth 4+ with support for AptX and AptX HD, long battery life, great sound quality. The additional gimmicks are where the points off came from. The smart pause part somewhat works for the most part, but I find it to be more annoying than convenient. I actually wish the settings for this weren't so binary as to be on/off. I actually really like the feature that pauses if I take them off entirely to put around my neck, but the single earcup lift-to-pause is downright obnoxious to the point that I may disable the feature entirely. When I'm adjusting the headphones to get a bit more comfortable (which I need to do somewhat often due to some comfort issues), the auto-pause starts to get really picky and will be constantly pausing/unpausing as I adjust the headphones on my head. This is triggered even if I don't lift up an earcup off my head, but instead just slide them around. This is compounded by the fact that when it's on its pause/unpause machine-gun rhythm, it doesn't always end in the correct state. This has resulted in several times where adjusting the headphones caused my music to end up paused and never resume until I interfered manually. This managed to happen 3 times while I walked around getting ready for work this morning... To make matters worse, tweaking the sensitivity in the app seemed to do exactly nothing. I have a feeling I'll be disabling this functionality entirely.
Overall, these seem like pretty good headphones, but I'm not entirely sold yet. In fact, I left them at home today and brought my PM-3 back to work due primarily to the knowledge that I can wear my Oppos all day in comfort while the PX made my ears sweat and created uncomfortable pressure points within only a few hours. I will continue to use these after work for a few days to see if they get more comfortable as they break in, and will update here if applicable.
(side note, if anyone knows a process for speeding up the break-in of the headband/ear cups I'd love to hear it - if these could just get a bit more comfortable I'd be MUCH happier. I can honestly live without the noise cancelling or the gimmicky auto-pause)