I have momentum 2.0, I wonder how it compares with PXC 550. Have you tried M2.0 before?
After getting the PXC 550's connected to my computers at home and work and my Samsung Galaxy Edge 7, I've been able to put some time on them in both locations. First off, my home system consists of a Dell Win7 Pro desktop connected to a Schiit Bifrost DAC via USB and Valhalla 2 amp driving a pair of Sennheiser HD700's. My source material consists mostly of FLACs played using Foobar2k and run the gamut from 70's & 80's rock to jazz classics like Miles Davis and jazz contemporaries like Diana Krall to all flavors of Berlin-school electronic music from the beginnings with Tangerine Dream to contemporaries like Chuck van Zyl. The music on my phone consists of 192 kbps MP3s of the same genres. No equalization was used but noise cancellation was enabled on the Bluetooth headphones.
First off, both the M2.0 and PXC felt confining when compared to the HD700's. I had to work to stuff my ears into the cups and seemed to always be fiddling with the fit. Other than that, both pairs are relatively comfortable for short term use. I tried sleeping with both sets while listening to some ambient electronic music and woke up after a couple of hours with the edges of my ears sore from being in contact with the headphone cups. The HD700, being a completely different beast, never gave me issues like that. With the M2.0, I use about half the adjustment range to get them to fit my big head. The PXC 550's appear to have the same adjustment range, but feel smaller on my head. Both sets are quite light to wear and bending over, I never feel like they are going to fall off. Bluetooth range seems comparable in both. In my apartment I can go about 25 feet from my computer with a water heater and electrical breaker panel in between before the signal begins to break up.
Noise cancellation - I can only say HOLY CRAP! This is my first exposure to active noise cancellation in closed back headphones but wow! In the apartment, I can have the washing machine going five feet away on the other side of a hollow wall and I would never know it was going! In fact, is was off for about 30 minutes before I even realized the wash cycle was over. At work, my lab has two flowbenches in it which provide laminar airflow to keep dust off of the high energy laser optics I work with. The airflow is generated by squirrel cage fans roughly a foot in diameter and are fairly noisy. When I turn the headphones on, that low frequency noise simply vanishes. Some of the lasers I build require high velocity fans inside their power supplies to provide adequate cooling. The noise from these fans has a higher frequency distribution and neither headphone can effectively eliminate that noise. I have no idea how either pair would perform in an airplane during a flight. I think they'd work ok, but the higher frequency from the jet turbines might prove difficult to eliminate.
Pairing of both sets of cans went very smoothly with the phone but I ran into a hiccup when pairing to both computers (both Win7 Pro boxes). One of the drivers the both headphones wanted could not be found during installation and with the idiot-proofing done with the drivers, I have no idea what functionality is missing. Basic functionality of pause/next song/previous song seem to be there, but operation isn't very consistent when connected to the computer. The manuals do state this however and trying to find driver updates has been fruitless.
Ok, now the big question...how does the sound compare? With my ears and my music, I have to say the PXC 550 has a brighter, cleaner sound. The mids with the M2.0 appear to be somewhat muddy to me with certain songs. It's not always apparent, but in a couple of songs like Adele's "Hello" and AC/DC's "Hells Bells" for example, there is a lack of definition. There is plenty of bass but it's not overpowering. The highs are quite clear in both, but I would have to give the edge to the PXC. I guess in my mind, the best test was with Stevie Ray Vaughan's "Chitlins Con Carne" off The Sky is Crying. The PXC sounded so much like the HD700 I was surprised. The bass from the kick drum seemed to be punchier through the PXC - probably the difference between closed-can and open. The cymbals were very crisp in both and what I believe were Humbucker pickups on Stevie's guitar were very clean. While the M2.0 still sounded good, the sound was veiled.
If you were only to buy one set of Bluetooth headphones which would I recommend? Depends on what you are going to do with them. If you were using them at home in a relatively quiet environment but wanted the mobility of Bluetooth, I would have to recommend the PXC 550 with its slightly cleaner sound. I think in a noisy environment that's a little rougher, like at work or when traveling, I would probably go with the M2.0. The slightly veiled sound of the M2.0 would be lost in the noise and their construction seems sturdier and I think would handle the jostle of traveling better. Also, I am NOT a fan of how you turn the PXC's off! Having to turn
both cups 90° is cumbersome and keeps them from folding into a more compact package for travel. The M2.0's discrete button is so much better in that regard, and folds up more conventionally.
Finally, Sennheiser has written a companion app to use with the PXC 550. I have not tried it yet but am somewhat reluctant to use it because it puts another layer between the music and my ears. It does have a lot of functionality and provides what I believe is some fairly flexible equalization among other features. I have not tried either headphone wired and really have no plans to. I tried to keep my rambling to a minimum and provide my experiences with my new toys and hopefully this will be of some use to someone.
