Sennheiser PXC 550 Headphones — Review

How do they compare to the competition? Are they audiophile worthy? Let's examine how Sennheiser's unit aimed at the business commuter and traveler fares.


Background

Having switched from commuting by car to commuting by train to my office, and after dealing with IEMs for a while in this setting (using the RMA RH250 and the Sennheiser IE-80), I found them far too inconvenient and uncomfortable for constant use. In addition, I usually sit in the wagon closest to the engine — a very noisy environment, making something like my Beyer Dynamic DT 770 Pro 250Ohm rather ineffective and inconvenient to use.

After a few talks to my fellow semi-audiophile friends and trying out a friend's Bose QSC 35 pair during a trip we did together to Berlin last December, I was convinced I could solve my problem by buying a Bluetooth Noise Cancelling pair of cans.

Over the course of two weeks I have evaluated 4 different pairs of headphones: Sennheiser PXC 550 (this review), Sony WH-1000XM2, Bose QSC 35 II and the Bowers & Wilkins PX. I will use these along with the DT770 as a wired fallback to compare the sound of the PXC 550.


Build

The PXC 550 feel rock solid. The satisfying click when you turn the ear cups to their normal position from their flat resting stance feels great, and apart from the flimsy vinyl in the ear cup, everything else seems roadworthy.

The provided case is nice but bulky, so I prefer to just carry them loose inside my backpack. Their build leaves me without a single worry that they would break or that something bad could happen to them without their protective case.

Accessories

Included in the box are:

  • A nylon covered carrying case lined with felt on the inside. It's shaped like one of those old CD carrying bags, like the letter D.
  • USB to micro USB charging cable
  • 1/8 inch cable to connect the PXC 550 to a non-bluetooth source

Bluetooth implementation

One of the great things about the PXC 550 is being able to connect to both your smartphone for notifications and laptop for music at the same time. It does stop music playing from your laptop to play a notification sound which can be disturbing at times, and is definitely inferior to Bose’s implementation of this, but still gets the job done and is better in that respect than the B&W PX or the Sony WH-1000XM2.

It supports the AAC and aptX codecs, which supposedly sound better. I can vouch to the sound quality being better when playing FLAC format audio files from my laptop and using the aptX than when using other codecs from my Moto G5 Plus phone.

Controls

Sennheiser got pretty creative here. There’s a touchpad on the right ear cup that you can use to increse volume (slide up), decrease (slide down), change to the next track (slide right), previous track (slide left), play/pause (tap). I have seen somewhere that it’s also supposed to activate the external microphone and let some sound in when you double tap. I wasn’t able to make this happen, but maybe I just don’t know how to?

I found myself accidentally activating the touchpad quite frequently, either when moving my hair out of the way with the hands, scratching my head, adjusting the headphones around the head, or (as it would seem) my weird habit of tapping to the beat of some tunes on the ear cups which I never noticed I have. Your mileage may vary.

App

Sennheiser offers their CapTune app for smartphones, and using the app you can finetune the signature of the headphones to your liking. The app has an “FX” section which offers some presets or the Director mode, which allows you to choose the bass response, simulate a listening environment (distance / size) and turn normalisation on and off. If you find the upper mids in these cans overwhelming, you might wanna switch the bass to “Rumble” which increases the extension of the bass range while taming upper mids and low highs a bit.

The app also offers a music player, and only when using the built-in player can you adjust the equalizer using the app. It does not support Spotify, Apple Music or Deezer, nor does it support FLAC encoded tracks, so you probably won’t be using it much unless you carry around a large collection of high quality AAC or MP3 tracks in your phone. This seems to me such a missed opportunity, as the EQ could’ve easily been built into the firmware of the bluetooth DAC same way the "fx" were.

Noise cancelling

When used on the train, the noise cancelling on the PXC 550 is enough to keep the hum away. In the office though, voices can still get through, and you’re out of luck if you’re in an open plan office where 3 simultaneous conversations are going on while you try to focus.

Usually noise cancelling leaves you with a sort of “pressure” feeling, and I feel this is less the case with the PXC 550 than with the other noise cancelling headphones I have tested.

In comparison to the other pairs, I found the PXC 550 to probably be the least effective in keeping out noise at the office, but okay for the train, and probably for a long flight.

Sound leaking

These phones leak a reasonable amount of sound to the outside world. I sometimes get strange looks from a co-worker when turning them up and then I know I’ve gone too far. It’s not like they go very loud either, as there’s a built-in volume limiter. Something to keep in mind if you work at a silent office, or don’t wanna disturb your fellow passenger’s journey on a plane/train and like your music loud.


Sound

Okay, time to finally properly evaluate the PXC 550 on it's sonic merits. Overall, these headphones have the most distinctive sound of the bunch. The PXC 550 have a general airy sound and can be sometimes aggressive, but is the closest to audiophile quality a noise cancelling bluetooth headphone pair has even gotten to.

Soundstage

The soundstage in the PXC 550 is a delight to the ears. Things are spread far and wide, without losing any dynamics due to that.

Using the Director fx setting in the app and choosing the Medium or High reverb settings will make the soundstage even wider and deeper, at the expense of transients and attack. Certainly a delight when listening to piano ballads, acoustic guitar driven songs and classical music.

Detail

Separation between the frequencies is perfect, and one can definitely hear the different parts in a song, and discern the different instruments to great precision.Out of all 4 headphones I tried, this was the only pair that allowed me to discover new details in songs that I hadn’t noticed before.

Dynamics

Snares and bass drums come alive with the PXC 550 in rock songs that survived the loudness wars. Listening to classic records like Metallica’s self-titled album from 1991 or Dream Theater’s Falling into Infinity reveal the PXC 550’s capacity of excitement and intimacy. While not punching as hard as the B&W PX, they still retain quite a bit of punch, and if you need more, you can switch on the “Thump” mode in the Director setting of the FX section in the app.

Sound signature

Fans of the brand will instantly recognise Sennheiser’s signature in the midrange of these headphones. Here’s a breakdown:

  • Bass: Definitely audible. The bass on these cans is not overwhelming, nor clouding of the other frequences. It is punchy and present, and the standard setting is definitely enough for me. People who enjoy more bass should go to the app and turn on “Thump” boost mode for more upper bass frequencies, or “Rumble” for that punch in the gut low bass hit. More than enough bass for anyone with all these options.
  • Upper bass and low mids: The upper bass is the closest to flat I’ve heard when trying all the bluetooth headphones. It’s there, it does the job, it’s not recessed, nor is it presented upfront. Guitars have a good weight to them, you can definitely tell the notes being played by the bass and discern bass and kick drum perfectly. Male voices are well represented and never sound thin.
  • Midrange: The midrange is definitely a bit heavy on the 3–4 Khz which might not be most people’s preference, but is what gives this the typical Sennheiser sound signature. It is not such a bump that guitars become fizzy though, and it’s not too disconnected from the 1–2 Khz range that would give you an impression of disconnection between the body and snap of a snare or between the low end and mids of a guitar. It does favour female vocals over male vocals, giving them breath and sharpness that other pairs I’ve tested fall short of. Male vocals are well represented, but don’t benefit as much from these headphones’ sound signature.
  • Highs: Here is where the Sennheiser eats the competition alive. The highs are pleasing to the ear and never show any signs of sibilance. Acoustic guitars and cymbals come alive in these headphones like no other I tested. That, coupled with the incredible soundstage they have, makes for a very pleasing sonic experience listening to any music that has lots of detail in the high end. What it also does is show every single flaw in the source material, so all those pesky 128kbps MP3 files and low quality youtube videos are going to sound pretty bad in comparison with good sources.

All in all I’d say these are definitely the most audiophile-like bluetooth headphones I’ve tried on. I liked this one so much I got curious about what I’m missing with the HD1 / Moment wireless, so I will be getting that to compare. Some reviewers seem to think the HD1 sounds even better, is better built and is more comfortable, so I look forward to reviewing them.

Comfort

After wearing the PXC 550 on my way to work, at work and on my way back home with the train for 2 weeks, I can confidently say they're pretty comfortable.

Other headphones grip my glasses and push them down into my nose, the PXC 550 don't do that. They don't get uncomfortably hot on the ears, although they are also not as comfortable as the Bose QSC 35 II which remain cool for a whole day, despite having their ear pads made o cheaper material.

The ear opening is not big, but I have slightly bigger than average ears and they still fit me quite okay without becoming on-ears rather than over ears. I imagine someone with really large ears could find them uncomfortable.

I find myself readjusting the headband every now and then, as they do put some pressure on your head if you haven't stretched them properly when putting the headphones on.


Conclusion

The Sennheiser PXC 550 are a solid pair of cans that are a joy to use on the go. Despite being what I consider the best wireless bluetooth headphones I’ve tried so far, the PXC 550 still fall short of the greats. At the same price point, it has some tough competition from the HD 599 and even the HD 650. Maybe not a fair comparison as you definitely need a proper amp to drive those and they are open backs, and maybe half of the price you pay on the PXC 550 goes to the built-in Amp/DAC, but still, the classics offer better audio for the money.

That said, the truth is, all of the wireless headphones I tried around the $300-$400 price range sound like sub $100 wired headphones. When comparing them to my Beyer Dynamic DT 770, Grado SR80 or Sennheiser HD 595 and HD 559, I’d say it’s closest to the HD 559 in terms of sound quality.