Sennheiser MOMENTUM

 Hi, Head-fiers. This is my first post as a newbie in the forum.
 
 I will give a short introduction of myself. I am 18 years old currently studying in high-school. I love headphones because I play Music since 6 years old. Currently, I am a member of School Orchestra( Tubist & Oboist) , Pop  Band(Keyboard) and taking serious lesson on Classical Piano (Currently in Diploma level). I love to listen to all kind of music.
SENNHEISER MOMENTUM REVIEW=
 Firstly, Sennheiser Momentum is a premium headphone which is quite expensive, I bought a pair for S$529 or about US$439. So does it really worth the premium price tag? let's talk about it
 
Sound quality:
 
 I am amazed with the sound quality of Momentum because it really produced a wide-sound stage and good imaging for such a small& light headphone. Likewise, it has a good imaging like one that you can experience from open-back headphone such as HD500 series or even the HD600. Moreover, the natural sound reproduction is just amazing. For instance, you can feel the snare drum as if being hit in the Concert Hall when you really feel that you are in the concert hall at the moment.Furthermore, the Bass response is adequate but might not satisfy Bassheads "take note" this headphone does not have that lower frequency boomy effect but it is just sufficient and adequate. According to my listening experience, this headphone has a slightly emphasize on upper bass or probably Tenor range. For instance, you can hear the Cello and Viola kind of dominating the pieces and they really shine and therefore creating Warm feeling. Oh yeah guys, this headphone is notorious for a wam sounding signature so you know what kind of Music you should look for when listening to this. Likewise, the Highs in this headphone might be slightly rolled off but still sparkle and shine. The Mids is amazing, it just appear to be natural and warm sound! The Lows is natural as well with Neutral bass impact without muddy or overpowering the mids and highs. By the way, you don't need amp to use Momentum headphone as it is only 18ohms impedence but you can bring small portable amp such as FiiO E6 or E11 for your daily commute to enhance the overall sound quality. In conclusion, the overall sound quality is good for general purposes.
 
Build Quality:
 
Again, The build quality is top-notched. Firstly, the Genuine lambskin leather is just amazing for the comfort! From the headband to the ear cushion is a Genuine leather.Secondly, the metal headband is very strong such you can stretched it all the way 180" and it will not break, very very Durable! And, one of the modern innovation of replacable cable is really a plus. Overall, I found the build quality to matched the Premium price tag 5/5.
 
Comfort:
 
This headphone is very comfortable to wear for travelling or daily commute. This is because, the Headphone is so light that you can move around vigorously as much as you want and it will still hug your head like a pillow tightly but it does not irritate you at all. One of the most comfortable travel headphone that I have ever used. Here is my rating 4/5.
 
Design:
 
 This is gorgeous, one of the most beautiful headphone design that I have ever seen in my entire life. The design is simple but attractive and luxurious!
However, It will be great if it comes in more variety of colour, currently Brown and Black is on the market. It would be great to see some dark Blue, Dark Green or some Dark Red to the market, If Sennheiser ever see this post and really think of my Idea, they will have a great time in the future for average consumer market
 
 
Value:
 This headphone is for those who only could spend their time listening to music while travelling or on daily commute. It does provide audiophile sound quality. However, if you prefer to listen at home I'd suggest some cheaper headphone out there that sound similar or even better such as HD449 or HD439 and HD558 Sennheiser. Moreover, musical preference does matter. Those of you who listen to Rap, R&B, Hip Hop Music might not be satisfy by the amount of Lower Bass provided by this headphone tough this headphone is also marked as "Bassy headphone" but it is just not enough for you , sorry to young people, but this really works well with some Dubstep and modern Kpop Music or you can try to listen to Twist7- Ghetto Bass (Soundtrack of HeadFi TV) and this headphone will really shine on that too. In Conclusion, This headphone is for those of you who appreciate on all aspect whether it's how they look, comfort, portability,sound quality and build quality. In My Opinion, this is one of the best headphone for portable use, not the best sounding but the best for your daily commute.
 
-- Please pardon me for my broken English, because English is not my first language and I failed my English language in class, pardon mee!"
 
Love Head-Fi , Peace.
 
Joshua Li, Singapore.

Along with the summary below, I have made a review thread comparing the Momentum with the Sony MDR-1R, MDR-Z1000, Logitech UE 6000, Audio Technica ATH-M50 and AIAIAI TMA-1 here:
http://www.head-fi.org/t/639948/review-closed-portable-circumaural-around-ear-headphone-comparison-m50-z1000-tma-1-s-momentum-ue6000-mdr-1r
 
I also made a Youtube review if you would like to get a better look and brief review of the Momentums. Please check out my channel for more reviews!
 

 
A Short Summary
 
BUILD
 
The Momentum is a well-built portable with a super lightweight and comfortable design provided that your ears are not too large for the earcups. For me, parts of the pads sit on top of my ears, but because the leather is so supple and breathable this is not a huge issue outside of hot weather. The detachable mic cable with variable angle mic-plug is really clever, but unfortunately the non-mic cable does not come with this plug. Also on the earcup side the detachable cable is a 2.5mm jack with a very narrow space for insertion which makes aftermarket replacement a little more difficult. My biggest gripe is that they do not fold up into a more compact shape.
 
SOUND
 
The Momentum's have a dark, rich sound with very fast, tight and deep bass. Mids are also very clear with a glossy bell tone clarity. Treble is definitely relaxed - there is a slight peak to lend the sound some sparkle / shimmer, but overall it definitely takes a backseat in the signature without sounding veiled like, say, the B&W P5. The soundstage is clean, with good definition of where instruments are. However with the treble roll-off the soundstage is inevitably quite intimate. The Momentum is quite versatile with genres but does especially well with modern studio recordings.
 
Conclusion
 
The Momentums are fairly expensive but offer a portable package with some of the lease compromises I've seen. Really excellent sound (provided you like darker signatures) and a good build. I've owned them for almost a year now and I love them!

I really can't say enough about how much these headphones blew me away when I picked them up. My only previous 'high-end' headphone purchase was a pair of Audio Technica ATH-M50's, and while those aren't exactly collecting dust, these have become my go-to pair of headphones.
 
Audio quality is superb. Bass is warm but controlled, and fun to listen to, coupled with very detailed mids and highs. I did at first notice that the treble in certain tracks sounded a little strange, though I've since discovered that the tracks appear to have been mixed that way, since most of the music I listen to doesn't exhibit this phenomenon, and its occurrence did decrease as the headphones were broken in. They function equally well with music, video games and movies/etc, and can just as easily be driven by a computer or amplifier as they can be from a mobile phone (in my case, a Galaxy Nexus). Plus, they tend to isolate very well, and at least in my experience, don't leak sound very much at all, allowing me to crank the volume up in public without being a nuisance.
 
The brown leather and steel design is extremely attractive, and the soft leather earcups are absolutely the most comfortable thing to touch my ears, despite, in my case, not quite achieving the advertised circum-aural fit. They have a very gentle clamping force, though they remain firm while moving around such that I can't shake them off my head if I tried. The simple nature of their construction gives me great confidence in their ability to survive rough handling, and while the detachable cords are somewhat thin, they are sturdy and coated in a sort of rubberized anti-tangle solution that works extremely well to prevent those kinds of stresses. The included mobile cable with inline mic is a nice touch, but the controls unfortunately don't work for Android handsets, relegating that cable more or less permanently to the box (or at least until I get an iOS device).
 
Even though these are marketed as mobile headphones, I find myself reaching for them no matter the occasion, and they never disappoint. Highly recommended.

INTRO

I have been enjoyably appreciating the Sennheiser MOMENTUM since just before Christmas 2012 and continue to do so now as I type this. 
 
The MOMENTUM is part of Sennheiser's Club Orpheus* flagship range of products - which also presently includes the HD 700, HD 800, RS 220, and IE 800 headphones as well as Sennheiser's newly released headphone amp the HDVD 800 / HDVD 600 - and is a beautifully-construced headphone with a high-quality sound that works well in a variety of listening settings.
 
DESIGN
 
Packaging


 
The MOMENTUM's packaging is similar to that of the Amperior (another recent and well-made addition to Sennheiser's product line) and by brief comparison is a definite improvement. Whilst the cardboard documentation holder that came with the Amperior has a tendency to fall out each time I open the box, the documentation holder of the MOMENTUM is securely epoxied in place and stays put when I open the box. It's a subtle improvement and one that shows me how Sennheiser are committed to improving their product line in every way, right down to the smallest detail.
 
After writing the previous paragraph I read the Amperior documentation where it reflected my statement and spoke of Sennheiser's dedication to "perfection down to the smallest detail." Need I say more.
 
The MOMENTUM's packaging has a blue band at the bottom that is similar to the packaging design of Blu Ray discs, which to me are often desired over DVDs. In that respect MOMENTUM is aptly packaged, as for me it is a more desirable headphone that many of the other similarly priced headphones currently available.
 
Carrying Case


 
The carry case for the brown/metallic MOMENTUM is a brown colour and is sturdily-constructed. It's wonderful to have a solid-yet-stylish case to match the modern-retro design of the MOMENTUM which contributes to my reassurance of the headphone staying in fine condition and my vision of an enjoyable duration of my experience with it.
 
Remote Control


 
The MOMENTUM's remote control cable is a thing of beauty. It is gorgeously-constructed and bends to terminate in either a straight or L-shaped jack plug. The buttons of the stylish and robust silver-coloured remote panel operate my iDevices with a satisfyingly subtle click. 
 
I find that the spacing of the buttons allows for accurate functioning of the remote control. With other iDevice remotes I have found their buttons to be too closely spaced together and arranged in a way that sometimes my intention to adjust the volume would pause, fast-forward or rewind a track I'm listening to or even end a phone call, but every time I use the MOMENTUM's remote control, my intention for adjustment is met. The remote control is a joy to operate. It's a small detail and one that adds to the satisfaction of my listening experience.
 
Fit and Fashionable


 
The MOMENTUM fits snugly over my ears and feels great to wear. However since receiving it and listening with it in bed, sometimes to meditation audio programs, I have fallen asleep with it on a few times and afterwards noticed that my ears and scalp had a slightly dull ache from the clamping pressure. People using the MOMENTUM for shorter periods of time will most probably be happy with it, as I am, and for those using the MOMENTUM for many hours at a time they will most probably notice a subtle outward stretch of the MOMENTUM's headband to sufficiently to reduce the clamping pressure to a lesser level.
 
The MOMENTUM is available in two colour-schemes, brown/metallic and black/red, the latter being a similar colour scheme to the immensely popular black/red coloured Beats headphones. I have the brown/metallic colour and love that it complements the colour of my red hair and the clothes that I wear, so much so that I've already (and gladly) worn the MOMENTUM as a fashion accessory/ear warmer when not listening to audio with it.
 
SOUND
 

 
Enough foreplay. Let's talk about the MOMENTUM's sound. The MOMENTUM has the highest quality sound I have yet heard from a portable headphone and all things considered, I find it to be very enjoyable.
 
"This is awesome" were the first words that came to mind about the sound when I listened with the MOMENTUM to a track from Donald Fagen's album Sunken Condos. Everything sounded well balanced and quite neutral, though compared to my HD800 there was a noticeable lack in treble extension. The sound of the MOMENTUM is slightly on the warm side of neutral and due to its closed-back design provides a great deal of bass resonance, ideal for people using it when outdoors or in a noisy environment.
 
With the Jimi Hendrix/Band of Gypsys track "Power to Love", the MOMENTUM works a treat. Jimi's guitar sounds warm and refreshingly analog, Buddy Miles' drums sound dry and punchy, and Billy Cox's bass sounds full and slightly boomy as it vibrates in the MOMENTUM's earcups. At times, and being used to the HD 800, I wished the sound of the MOMENTUM was slightly less resonant, but when I started to listen to the details of the bass part on this recording, I could hear all the detail I wanted to hear, so thumbs up there. When the band kick in at around 0:19, the sound from the MOMENTUM rocks whilst retaining great attention to detail. Brilliant!
 
I enjoy listening to ambient music and sometimes guided meditation CDs. For me the smoothness of the MOMENTUM's sound works very well for those purposes facilitating a subtly detailed sound that is pleasurable to listen with.
 
Comparison with other Sennheiser headphones


 
I'm writing this part of this review following a festive holiday in Germany where I also had the Sennheiser HD 800 and was editing some video footage of one of my recent musical performances** that I filmed with my portable digital video camcorder, which was positioned close to the drum kit I used in the video. The sound recording was quite clear overall but the sound of the hi-hats and cymbals was quite hot and slightly distorted. As I edited the footage I switched between the Amperior, the HD 800, and the MOMENTUM, and for the vast majority of my editing time preferred using the MOMENTUM due to how it softened the treble frequencies in a way that I found non-fatiguing and more palatable and enjoyable than with the Amperior or HD 800. The MOMENTUM's lesser ability to reveal as much micro detail as the other headphones was always more than enough and enjoyable. If there's one common factor true about my experience with the MOMENTUM so far, it's that I always find it very enjoyable.
 
The MOMENTUM and the HD 600, HD 650, and HD 800

When listening to some Jimi Hendrix Experience recordings I was curious to hear how the MOMENTUM compared with the Sennheiser HD series headphones. First I switched to the HD 600 and the sound felt a bit cold and flat by comparison though more neutral and revealing of instrumental textures and overall sonic detail. The HD 800, a much more revealing headphone that the HD 600, sounded fuller than the MOMENTUM and provided a much crisper and detailed sound, baring every nuance on the recording, especially in combination with the Lavry DA10 DAC/Amp. Considering the price of the MOMENTUM I found it held up very well with the HD 800, and whilst there's obviously no comparison between the technical capabilities of the MOMENTUM and the HD 800, I find the MOMENTUM every bit as enjoyable as the HD 800. I can imagine that there are many who may prefer the sound of the MOMENTUM over the HD 800, since the HD 800's ultra-revealing sound may not be to everyone's liking. 
 

 
In terms of my listening preferences - and this may be because my default go-to headphone is the Sennheiser HD 800 - when I have used the MOMENTUM for practical and analytical close-listening purposes including when learning song arrangements and drum parts for a gig, I have found the sound of the MOMENTUM to be slightly lacking in treble emphasis in relation to what my ears would perceive as 'natural' e.g. if I am at a concert and listening to a musician play live. This can of course be corrected by applying EQ via an iDevice's treble boost setting or using a portable amp, but all things considered I would prefer it if the MOMENTUM's sound had slightly more treble emphasis than it does. However the MOMENTUM'S stock sound remains excellent and I've enjoyed it every time I've listened with it.
 
Having tried some of the finest flagship headphones currently on the planet and listened to them critically, I have enjoyed them and also discovered many faults and discrepencies in their sonic characteristics, usually to the point of hearing the headphones and not enjoying the music that much. Since receiving the MOMENTUM and mainly listening to audiobooks and a miscellaneous selection of music in many styles. I've mainly just been enjoying the listening experience with the MOMENTUM, happily able to hear all the details in the recording that I want to.
 
Overall, surprised at how well the MOMENTUM performed with the HD 800, I find that the MOMENTUM has a high performance/price ratio and fares as a high-quality headphone that, unlike the HD 800, excellently lends itself to portable use.
 
The MOMENTUM and the Amperior


 
Compared to the Amperior, a similarly-priced headphone by Sennheiser also well-suited to portable use with iDevices, the MOMENTUM has less sub bass resonance and emphasis and less treble prominence. That reminds me of how the HD 650 compares to the HD 600 in those areas. The MOMENTUM is no slouch in the bass department though and can ably deliver a viscerally-impactful sound, which in combination with it's closed design are qualities I find work very well for a portable headphone. I find, though by a small margin, that the MOMENTUM isn't as effective in providing as much clarity as the Amperior in noisy environments. For example, when in Germany editing the video footage I previously spoke of, there was some Christmas music playing in the background. With the Amperior I heard all the details I needed to hear when editing over and above the music playing in the same room and without turning my headphones up to a painfully loud volume, but the bass wasn't as clear and impactful when I used the MOMENTUM, which is something that people who normally use their headphones in noisy environments may wish to consider if they are choosing between the Amperior and the MOMENTUM and looking for the option that provides the most sound isolation.
 
The sound of the MOMENTUM is less upfront and more laid back than the Amperior, which is very adept at revealing musical details as is the MOMENTUM, though the latter seems geared less towards analysis of mirco-detail and more towards enjoyably listening to music, and according to my ears, it very much succeeds in that. Another significant sound difference is that the MOMENTUM offers a more spacious and open window to peer into recordings than the Amperior which portrays recordings with a more compressed, upfront, and intense sound.
 
OUTRO / SUMMARY

The MOMENTUM has proven a very neutral-sounding headphone which I have found enjoyable with all audio I have fed it. I have only had a desire not to use it for listening when wanting to compare it to another headphone or when watching movies or gaming, for which I prefer a brighter-sounding headphone that enhances the crisp visual detail on screen, but that's just my preference. The MOMENTUM can of course be enjoyably-used for all listening purposes, though some users such as audio professionals may want a more soncially-revealing headphone.
 
I think that for most music lovers who listen to music using an iDevice and/or a laptop or desktop computer and want a veratile headphone suitable for both purposes, purchasing the MOMENTUM - and a great value USB DAC/Amp such as the FiiO E17, which I also highly recommend - could very well be the best of both worlds.
 
The Sennheiser MOMENTUM is a fabulous choice for anyone wanting a stylish looking headphone that also sounds great overall. It works great with pretty much every audio I feed it, and with Sennheiser's readily available spare parts, could be a headphone than can be cherished for life. I highly recommend the Sennheiser MOMENTUM.
 

 
*More info on Sennheiser's Club Orpheus range of products can be found here: http://www.sennheiser.co.uk/uk/home_en.nsf/root/club_orpheus_club_orpheus_about
 
** Here is the video footage I edited with the MOMENTUM: Windsor with the Revelators - 2012 - part 1 - YouTube
 
P.S. here's my video review of the MOMENTUM
 

Before you read this you should know that I have only tried them for a couple of minutes and this is my experience of them under those minutes and this is all from my own preferences!
 
The headphones is overall good and the sound is balanced BUT! They are a little to balanced to fit my preference. As I said the sound is really balanced but the lack that little extra to make me get that feeling of overwhelming pleasure. Most of the reviews that I read through before I tested them said that the headphones was a little more bass heavy which of course made me happy since I like that little overwhelming bass since I listen to rather bass heavy music. I am sure that they are really good for those who listen to classical music but I would not recommend these headphones for those who like bass heavy music. The reason to why I gave it three in rating is of a different matter. When I talked to the employees  from Sennheiser they told me that momentum was the newest in sennheisers "on the go headphones" witch I think is wrong. Perhaps it is my head that is to small but I think that they leaked way to much to be a good pair of headphones when you normally travel with the subway.

This was my first real headphone purchase since some Shure E2Cs years ago.  They flat out rock.
 
They were designed to sound great from a smartphone if need be.  Inline iPhone remote/mic on the cable is nice.  The sealed over ear design keeps things quiet on a plane..for myself and the person next to me..
 
Design is nice, although I suppose some people will care more or less for it than myself.  I'm mostly drawn to the attention to detail, build quality, and performance.  The leather ear cups are super comfortable, nice touch.
 
Maybe not as transparent as the 598s and up, but it doesn't need to be.  Recent travelling has been much less of a chore.  Big fan.

To come

I have been in the market for a top notch pair of headphones for portable usage for some time. After trying a number of pairs at JBHIFI and Jaben in Melbourne, I eventually settled on the Sennheiser Momentum. I live with 2 others so a headphone with solid isolation and no sound leakage was needed, but also to be a portable pair was needed. These were perfect.
 
So upon getting home I opened the packaging. Right away we have a solid carrying case, which is rather bulky but definitely is capable of protecting you HPs quite easily. We also have a 1/4 adapter for your headphones 1/8 jack, we also have a second cable in the circumstance that your other one breaks. Outside of that there is a 2 year warranty with Sennheiser.
 
Design wise the Momentum has a stainless steel band with a leather headband. The pads are leather, and even after extensive usage both indoors and outdoor in heat, they do not make my ears feel hot or sweat at all. They hug my head slightly but never feel tight enough to be uncomfortable. I find the the pads are actually quite small and fit just on part of my ear and not over it entirely, this worried me at first. However as I soon found out this results in the pleasant knowledge that little sound leaks at all. The build quality seems quite durable and you can tell this phone is not a cheap model.
 
My testing songs for this review after burn in and before are
 

Rom Di Prisco - Troposphere

Ne Obliviscaris - and plague flowers the kaleidoscope

Deftones - Romantic Dreams
Freaky Mind - Kill
Nas - N.Y State of Mind
Diablo Swing Orchestra - Voodoo Mon Amour
 
Out of the box, I was very impressed with these phones. I'm running them for a Z series sony Walkman and a Hippo Cri Cri portable amp. The ohm rating of these phones ensure you should easily be able to get plenty of potential out of them with a portable device.
 
I found that the effects of burn in were minimal with these phones. The soundstage is fairly broad and the instrument separation is very defined. Overall the headphones have a tight but very present and punchy bass. Mids are a tiny bit recessed but nothing that is too noticeable. Treble is smooth without major sibilance or grain. The sound is not colored, and is very natural and transparent. I did find that a number of older rock and pop records had their flaws quite noticeably exposed by these phones. 
 
As far as performing on each of the tracks, the soundstage and instrumental definition were more than enough for the complexity of Ne Obliviscaris' mix of classical and heavy metal, while crushing guitar riffs sound powerful, fast and the bass has impact. For hip hop they are extremely clear and fantastic for vocals, but the beats may lack impact compared to basshead phones. Deftones track was highlighted with amazing clarity, soundstage and very impacting lower mids. For electronic music I found these phones were more than adequate.
 
On the side of value I would say that the 389 dollars that I paid for them was definitely a bit pricy, especially thinking of Australian prices. However they have definitely paid off as these blow my Sennheiser 439, 418s, 280 HD, Sony SA-1000 out of the water quite handily.
 
Overall I'd say these are a fantastic portable headphone if you are interested in fantastic isolation, comfort and natural well balanced sound, all while being able to be driven by most portable devices.

I've been listening to these headphones everyday for a full month, and I gotta say I loved every minute I've listened to them.
 
OK, so I might lack experience doing this review because these are my first true high quality headphones, and I have not listened to all the reference headphones out there, and lack all the lingo used in these forums, but I try to review them as a normal person who was looking for an audio quality leap. 
 
I come from the Shure SE215 and the Sennheiser HD449, and although they are quite good for their own merits, the Momentums have been a massive increase in sound quality. I'm not gonna say the typical "you hear stuff on your music you probably never heard before", but the music indeed sounds fuller, more natural, more lively. Instrument separation is greater, and you feel more immerse in your listening sessions.
 
I bought these headphones out of curiosity, I was quite satisfied with my older headphones, but I always wondered how a 300€ headphones sounded, what true quality sound really meant. So I bought them as an impulse, but haven't regreted since. Even when they are much more expensive than I was willing to pay for.
 
So now I'm gonna justify the stars given in this review:
 
Value: 5 Stars
 
Although I stated before that these headphones come more expensive than I was ever was willing to pay for a piece of metal and plastic, I haven't regreted. I payed a little bit less than the retail price, at 240€ these babies have a high value.
 
Audio Quality: 5 Stars
 
These headphones sound fantastic. Period. Everything feels so accurate, so natural, so full, so vivid. From the first time I put them on, I felt something different about them, it's not something you fall in love gradually as you discover what these phones are capable of, no. You love these instantly. Alright, I sometimes feel like the mids are juuust a bit recessed, but just a bit, sometimes the voice get lost in between the instruments, but only on some recordings. It's not something to call a flaw, more like a taste in sound signature, but it doesn't bother me that much, if at all.
 
I listen mainly to Blink 182, Green Day, Good Charlotte, and some other punk rock bands. I listen   to some Beatles, some Bob Marley, some 80's synthpop, some Metallica, some other thrash bands, some Jpop. And I can't find any flaw worth mentioning out of the generes I listen to. Guitars feel alive, specially Green Day's reefs. Voices feel live too, some Adele, some Air Supply, some Pet Shop Boys and Tear for Fears  are really something in these headphones.
 
OK so my source might not be the greatest (Xperia S), but it sounds very transparent and balanced.. Plugging them into my PC provide a  wider soundstage, and somewhat accentuated bass response, but they sound a bit harsh and tiring, alonside with some hiss on the background. I'm definetively looking forward into plugging them on a higher quality source.
 
Design: 5 Stars
 
So classy, so different from your average urban headphones. Everything feels high quality, from the steel of the headband to the softness of the leather pads. It is a mix of retro look and modern finishing. Very cool looking headphones.
 
Detachable/replaceable cable is a great addition, specially to me, who have had his bunny chewing a couple of headphones cables before.
 
Inline controls nor mic don't work on my device, but I wasn't looking for a headset headphone, If it worked it would have been a plus, not working doesn't substract points.
 
Confort: 4.5 Stars
 
They are very confortable. The softness provided by the leather pads feels great, the cushions seat around my ears as they were meant to be, although bigger ears might find them a bit unconfortable, for me they are just right. Clamping force is spot on, it neither feels too strong or too light. You never get tired of having them on.
 
I've rated them 0.5 points away from 5 stars because when I'm not wearing them on the ears I really don't know what to do with them, they feel very unconfortable being worn as a necklace. Sometimes I just let the pads like on my forhead to move the head around freely, because as necklace they really hinder your head movements. Maybe a minor gripe, but I'm always on the go, so I need some time to let my ears rest from hearing music, It's not like they sound harsh or tiring, but hey, having some peace and quiet is nice after rocking out for an hour or two.
 
So in the end I rate them 5 stars overall, because these headphones are outstanding, 300+ dollars might not be your everyday purchase for the mere mortals who don't have 5000$ to spend on a cable or an amp. But they are totally worth it. Look it more as an investment. And if you have some cash and you rock the streets everyday like I do, they are really the headphones to look into. Both for sound quality and outstanding urban look.
 
I think that's about it, excuse my rather poor english and lack of especialized words, but I wanted to rate them as the ignorant of the HIFI world I am.
 

Nothing major to add here. I have been searching for a long time for a closed portable that sounds good, looks good and is genuinely portable (ie. no 3m coiled cables). I think this is the closest to that I have found. They have a bit too much bass emphasis to be perfect but their detail, resolution and soundstage is excellent, which makes the bass less intrusive and they have a lovely smooth, thick but natural texture. They are also very forgiving of less than perfect source material and very efficient, which means they sound great straight out of your DAP or smart phone.
 
They are really well made, not quite as nice as the B&W P5, but very nice, much nicer than the Sony R1s. They are not truly over-ears IMO, the ear cups are too small to fit around any but the smallest ears, so they sort of sit half over and half on the ears. But what you lose in comfort you gain in a lower profile.

On sound alone, the Sennheiser Momentums are worth every penny. But aside from being wonderful sounding, the elegant design is beautiful and luxuriant with stainless steel band, real leather and quality plastic cups in a nice, dark bronze finish. The standard cable is also very high quality, with a substantial metal remote attached to it. 

The case isn't as large and bulky as I expected from reviews, and it's sturdy enough to keep the headphones safe under most circumstances. 

They are very comfortable. The light weight and the materials inside the earcups ensure the fit is great, with minimal headband pressure and without heating up your ears. The cups are on the small side, so if you have large ears you can expect a tight fit. Isolation is very good, not class leading but good enough to shut out most unwanted noises. 

Sound wise, Sennheiser really nailed this one. The Momentum is one of the best sounding portable headphones available at any price; they even are good enough to be compared to the better sounding sealed headphones out there meant for home use. I've been through most of the competition from Logitech, Ultrasone (specifically, the ED8), Sony, AKG, B&W, Focal etc and the only headphones I've heard that actually better the Momentum on audio quality alone are the recently released KEF M500s and B&W P7s. 

The sound of the Momentum is a little on the mellow side, with a mid-bass presence definitely (but tastefully) north of neutral and a treble to the other way around. And it's actually a good tonal balance for a portable headphone; because when out and about a bass boost is preferred in most scenarios, and the laid-back treble makes the Momentum forgiving with poorer recordings. But the great thing is that the bass isn't TOO much and the treble isn't TOO laid-back. And the Momentum has very good clarity so while the tonality is definitely dark and mellow, details and upper harmonics don't get completely smeared as there is plenty of detail resolution available. Putting aside the ups and downs (literally) at the frequency extremes, the Momentum is a very transparent sounding headphone. 

While always with a slightly thick texture, the bass of the Momentum is well defined and quite tight for a sealed headphone. Extension is very good and it doesn't feel very bloated or slow. And the treble is very good for a portable headphone, too. It has its issues, but for most people I think it will be appreciated, especially as it's so forgiving. 

And the midrange is among the very best I've heard from portable headphones. Rich, natural, yummy and open sounding. While the headphone does lack some soundstage depth and therefore can sound a little congested overall, the midrange itself on the Momentum doesn't feel closed in at all. The midrange transits into the treble very well. I have issues with the slight thickness due to the bass and the lack of upper midrange air and presence due to the recessed treble.  But other than that, things sounds very nice and inviting. 

With the Momentum, Sennheiser made the ideal on-the-go headphone. You get a transparent and natural sound that you can listen to for hours and that suits portable use, and you get this great sound in a portable, comfortable, practical and beautiful package. 

Great job, Sennheiser!
 

These headphones are surprisingly nice to look at.
The build quality is just awesome. the materials and the looks surprised me when I saw it even though I had extensively researched it before I bought it.
the sound did not disappoint at all either, pure, full of layers and details.

These sound really good for closed headphones: very good detail, good bass, fantastic mids, good highs without beeing too bright or harsh sounding. Jumping from v-moda m80 I found these more detailed and extended, expecially on the highs. The sound is also more airy and the soundstage more extended.
I also owned v-moda m-100 and while I think both are very good, I find momentum best for rock genres (like muse, radiohead,...) and as all-rounder  while I found m-100 best for dance, techno and electronic genres.

I'll add more when I have time...Sorry...

Will post more soon, but I tried them briefly, and was impressed.

This will be a very brief review because unless I discover otherwise, I will be returning these headphones to Amazon because the inline controls for smartphones do not work for Android phones; or at least my Motorola Droid 3. For $350, this shouldn't be an issue. The Sennheiser website has no info on phone compatibility but I purchased on faith given the company's rep (plus I've owned three sets of Sennheisers previously and have always been happy). 
 
I'm simply shocked that a set of cans designed expressly for mobile music players won't work with the stock music player for the most widely used OS out there.
 
Beyond that, the pads are very tiny, they barely fit over my ears; that's a minor complaint as it would have been entirely livable if it weren't for the dead inline controls.

 
The Momentum have a great classic retro quality style and fantastic sound to boot. Out of the box, the headphones are setup for a great listening experience for a majority of my music including R&B, classical, rock, Jazz, 80's, 90's, trance. Of couse, with a DSP you can tune it to your liking and the Momentum handles it very well. The case, although big, offers the protection it deserves. Not sure how Senn could have done that differently. Something unadvertised is the "noise-isolation" resulting from the ear cups - it actually works just as well (if not better) than some digital noise cancelling units. Yes, the ear cup sits on the ear and will touch the circumference, this is by design and offers the noise-isolation whilst being smaller and more practical.
 
The only gripe I have is that the connectors are not gold plated.
 
Quite frankly, I was blown away by these 'cans', very happy indeed. In my view - straight into the Hall of Fame for these.
 
>> I can't reply to comments below for some reason, I'll try to reply by editing this review <<
 
EDIT 1: The unit comes with two cables - one with and one without the inline remote which I thought was a useful touch. I walk around with these headphones and listen to them whilst on the move indoors and outdoors. Prospective buyers should be fully aware of the "context-of-use" before buying these. For example, if you are considering the Senn HD 650 then they are a completely different headphone for just sit down and listen. Please be aware of this when comparing headphones. The earpads are made from a high-quality english lambs leather. Yes, not Pleather that will rot away after awhile but the softest lamb leather you could imagine. I cannot imagine how anyone can get these headphones around-the-ear unless you are a tiny dwarf, and trust me I've seen dwarfs with large ears so these are definitely around-on-ear hybrid. I use the headphones with a software DSP and playback of lossless/hq-mp3 files on an iPhone. A DSP can seriously improve listening experience and these headphones are highly capable across the frequency spectrum. I have never felt I wish it could have more bass/treble. It's just right for me. If you try these headphones in the shop you might notice the weak volume (i know i did). Just check "sound-check" and "volume limits" are off. I have great hearing and 70% volume gives a pleasant listening experience. 

Very impressed with the Sennhesier Momentum's. Sound is fairly balanced with clear highs & lows. They're stylish without being 'in your face' like various brands such as Beats. The quality of the leather on the earcups is impressive and I'm finding that I can use them for a couple of hours at a time with no discomfort.
 
Using them straight into my iPhone 4S and 320kbps tracks from spotify is giving me excellent sound and I'm happy to use these without my Fiio E17 so that I can make / receive calls whilst out & about. Call quality is good and no one has commented on external sounds or sounding distant.
 
Sound isolation is surprisingly good and I'm happy to use these on my daily train journey into London and home. It also helps that the Momentum's are relatively lightweight compared to other headphones that I've used.
 
I love the case supplied, it's well thought out, lightweight and the biggest plus being that there is no faffing around having to remove the cable to put them away, a small compartment takes care of that. It is however slightly too bulky for my normal work bag - however I did buy that to tote around a MacBook Air + iPad, so it is smaller than most.
 
Overall they are stylish in an under stated way and sound is pretty impressive and I'm happy to use the Momentum's on a daily basis.
 
Bought in the UK for £250
 
Video review and pics below