I had several of those (balanced and unbalanced) and I liked them alot.
I can't remember if they had the newer "silver" drivers.
I compared them with the HD600 and they sounded better.

From a post of mine:
I realized something about the HD650, now that I'm listening to my 2nd pair (rebought ~6 years after selling my 1st pair): an immature listener might completely under-appreciate what they do, how they present recordings, have no idea and then just sell them like I did. It took me that many years to understand what I want and what I hear... It's hard to explain but at the moment I feel like these bastards will only be sold if I go deaf. They're just so competent, they shift my attention to music. The detail level is really good and the way they image is sorta enigmatic but competent and engaging. I can't say that I miss the soundstage or sub-bass of my bass-port modified Q701. It's like when you listen to HD650 you're in a world where other headphones don't exist, or the things that HD650 are incapable of are just irrelevant or don't matter. This second pair smells exactly the same as my 1st (I wonder what psyche-manipulating stuff Senn puts into that fragrance...).

BTW I think it's important to maintain the pads in good shape, replace them once they compress and especially replace them right away on a newly acquired used pair (mine is ~12 years old).

 

Massdrop x Sennheiser HD 6XX Headphones​

---

Let me start of by saying this is not what I would call a real review. This is more like a Tribute to a headphone that, while controversial, has been and is irrevocably deemed a classic reference headphone. Not just my posts but many reviews have referred to it or used as a headphone to compare it to.  The disclaimer is that I have known about this release for a while now and have been sent  a pair. Even so, given my long relationship with several pairs of HD650's I have no reason to shill these along side the fact that they will sell out very quickly anyhow. 
 

---

I have had 6 pairs myself with the HD6XX being my seventh pair. I have bought and sold this headphones for a myriad of reasons. It always seems to end back up in my stable because I have come to know it as consistently more spot on in tonality than just about every headphone I have heard. Some of the reasons for me selling them so many times was because I sold it them to help fund a new piece of gear or was in a honeymoon phase of something new that outperformed it in a particular attribute. Then later when I knew I had lost my bearings on how things were supposed to sound I would repurchase it again. 
 
Why were people asking if the Focal Elear was the super 650 they have always wanted?
 
Why do people ask if the the new ZMF Atticus are the closed back HD650's they have been longing for?
 
Why when the Audeze LCD 2 was released was it called the planar magnetic super HD650?
 
Could it be because  they are more expensive headphones with a darker than neutral signature? Well if so then why is it much less popular for someone to ask for a super Beyerdynamic DT880? or a super Hifiman HE-500 even? Such an opinionated and categorically diverse thing as music can't possibly have one tuning unanimously crowned as champion can it? Uhhh... well if it did, love it or hate it, like it or leave it, buy it or sell it, the Sennheiser HD650(or even HD600) is unequivocally the closest thing to having that crown as far as headphones go. Sure the HD800 is technically better but just because the prince is younger, brighter,  and faster doesn't make him king. The king would have to die first and as far as that goes the HD650 is apparently immortal. Relatively, the 600 is the more even tempered queen right by his side. 
 
Let's take a look around the web shall we:
This is without searching specifically for the HD650 but rather "best reference open back headphone". Some have their preferences but there is one consistently present. 

A quote from one of all of our favorite sources:
 
- "Well...they've changed their tune a bit with the just announced Massdrop Sennheiser HD 6XX because in this case they didn't change the headphone's tuning it at all. (Measurements show the HD 6XX and HD 650 essentially identical within measurement errors.) No, there is really no reason for them to re-tune the Sennheiser HD 650. They've done their homework. They know that this is widely considered amongst headphone enthusiasts the standard by which all other headphones are compared. I've reviewed them and love them. Yes, there are better sounding high-end headphones, but none deliver the price/performance ratio of this icon."

Read more at http://www.innerfidelity.com/content/if-it-aint-brokethe-massdrop-sennheiser-hd-6xx#qLHs1kALCTYimQT2.99

---

Looks / Comfort / Build​

1. Ear pads out of the box are slightly firm but deep and create a healthy distance between the driver and the ear.
2. The ergonomics have proven to be timeless and are a succession of previous designs used by Sennheiser
3. I won't mention the names of other manufacturers but I dare you to find a 650 that was delivered broken through shipping. If it does happen it is a lot more rare than with ____. You fill in the blank. 
4. The clamp pressure can be a bit imposing out of the box. 

 
 

---

Sound ​

1. Very dynamic and punchy without sounding aggressive. (Amp dependent so results may vary)
2. Good Microdynamics
3. Great Details
4. Non Fatiguing
5. A chameleon with down stream and upstream gear so heavily manipulatable. 
6. The treble can be grainy and/ or slightly dark to some but is smooth in balance with good resolution and extension
7. Wonderful midrange from the lower midrange all the way through to the lower treble
8. The bass is a bit rounded with a slight mid bass elevation for healthy kick drums
9. The sub bass can sound ill extended at times but for the most part is capable of handling even sub bass saturated genres(yet not effortlessly)
10. Can be modded to have very tight and controlled bass, even better clarity and cleanliness (very easy to mod)
11. Can sometimes sound slow and veiled to some when not properly amped or in stock version. 
12. Very scalable and reportedly becomes competitive with Top of the Line headphones when used with uber quality amplification
13. Soundstage can sound narrow to some but maintains adequate depth and layering for  relatively deep insight into recordings. However, in the grand scheme of open back headphones it usually sounds less wide and is said to have a small soundstage. Again, amping really helps the depth of soundstage increase. 
14. Though some believe it is a darker sounding headphone, It really works well with OTL tube amps and is revealing of system changes and improvements. 

---

​

 
 

MODDING​

 
 
There is a coin mod to be done by using a quarter to cut out a portion of the foam covering the drive; a removal of the back cover and adding Dynamat in specific places; and a  removal of  the foam from the back of the driver. (please put the cover back on). Be sure to scour the internet for more specific instructions. Rest assure that these mods are all VERY VERY easy. There are all sorts of mods..even some to make it brighter. 
 
The mods can give the following improvements:

1. Increase of bass control and perceived reach
2. More satisfyingly visceral bass slam
3. Increased speed
4. Faster Decay
5. Crisper and livelier sound
6. More openness and clarity

 
There may be more improvements and mods to do so this is by no means exhaustive, and again just a little boost to get you started. I personally heard the HD6XX and thought that they changed the tuning until measurements confirmed that they actually are the same HD650. I had become acclimated to the tuning of my modded 650 so upon arrival I was very disappointed with the stock bass in comparison as well as felt the headphone sounded slower. For 199 the HD6XX is a no brainer and a modded 650/6XX one will become legend if it already isn't by now...the stock version most definitely is. 

---

 
 

Amps I have heard the 650 on and personal rankings (of the pairings not the amps themselves)​

• Apex Teton
• Trafomatic Head 2
• Ifi iCan Pro 
• Bottle head Crack and Speedball upgrade/ Schiit Jotunheim 
• Cayin iHA-6 
• Airist Audio Heron
• Nuprime HPA-9 (a bit dark for it but good body)
• NFB - 28

---

 

 HD6XX VS HD650​

 
The aesthetics and accessories are the only thing to compare here really. But eh..why not?

1. The 650 comes with a longer cable terminated in XLR and an adapter for 1/8 jacks
2. The 6XX comes with a shorter cable terminated in 1/8 inch and has a 1.4 inch adapter. Why... possibly to be more compatible with portable amplification and transportable systems. Because by no means is it competitive with 'Beats' since people with those headphones most likely wont be using any amplifier
3. The 650 will still have the more luxurious or classy paint job as the 6XX is a plain midnight blue that can look black depending on the lighting used. 
4. Through and through the build quality is the same and they measure the same as well 

---

Conclusion​

When I started the "Massdrop Collaborations...What If?" thread almost a year ago I expressed how my choice would be for a 650 collaboration. While not quite black, I am sure Sennheiser had their reasons and I am very happy that this headphone is available at price lower than I have ever paid even for a used pair. These are good times to be an audio enthusiast. Not to mention the most recent release of the Schiit Jotenheim, now Music lovers can have a system I used to dream about for a lot less than a new 650 and Bottlehead Crack w/ Speedball upgrade would have costed you back then. I feel very humbled to have been able to witness this re-launching of an industry legend and know tons more people will be smiling from ear to ear as they listen to music "the right way" lol.. just playing anyway you choose is the right way for you.

This is my second-time owning the HD650, and I've taken a bit of this review from a post I made in the HD650 impressions thread.
 
I have some detailed analysis of findings my first time around of the HD650 in comparison with an LCD2 that can be read here:
http://www.head-fi.org/products/audeze-lcd2-planar-magnetic-headphones/reviews/13729
 
I'm going to keep it brief as by now you've probably read gushing reviews, and for the most part they are true. This is a great headphone. Perhaps all one ever may need.

Save yourself and your wallet, get the HD650, a decent amp / DAC and run far away from head-fi and never speak of it again. 

But if you are still here, you may need a bit more convincing. So I have a set of excellent classic LCD2s that measure and perform very well. In my second time owning the HD650, I've pitted them up against these high-end headphones for this review.  
 
The HD650 in my possession, a silver driver variant, is very very close in signature to my LCD2 classic, just a bit more mid forward, and lacking that extreme low-end extension. 
 
My LCD2 have more clarity, and you can really tell with bell tones.  There is a more separation between sounds, the HD650 takes on a slightly bit more of blurred sound in contrast.

But really, I'm splitting hairs. These are exceptional headphones, and damn they are much more comfy and lightweight. 
 
One test I was excited to put them through again was listening to binaural nature recordings, particularly rain, canyons, and deep thunder. Many people talk about sound stage with headphones, but its a mute point to me as the majority of music will have a proper stereo field only with 2-channel speaker setups. Both the HD650 and the LCD2 are capable of rendering 'holographic' spatial reproductions of binaural recordings - with the LCD2 taking the prize in reproducing the low ranges, but the HD650 just edges it out in naturalness on the upper registers, it just seems smoother on the high-end while still retaining detail. LCD2 has more depth though, you can hear 'further' into the soundfield. I've mentioned this in my comparison on these two headphones before, but the 650 has the edge here (it may have a bit to do with the distance of the drivers to the ear, with the 650 being a bit closer than the LCD2). It says a lot for their presentation. Yes, the 650 may lose in some technicalities, but for the most part its presentation is incredibly life-like and natural. Switching, back and forth between the 650 and the LCD2, the 650 just has a bit more 'air' on the top-end that when listening to sounds of wind rushing through a valley, leaves rustling around you, it just creates spine chilling realism. Listening to a recording of  the pitter patter of rain hitting the roof of a tent, something we've all heard at one point, the 650 has the right treble tilt to make this recording a bit more lifelike and 'above your head' than the LCD. Combined with its better ergonomics and light weight, and I'd have to say that the binaural experience on the 650 - the headphones just disappear. 
 
I would love to get a chance to listen to Stax SR007 again or even 009 and run them through some of the above tests. I'm sure I'd be impressed. But one has to marvel at high-quality, especially at the bargain price you can get these headphones for used. If you can afford new, they are still worthy as its hard to find this quality and comfort in its class-range. If you want to spend less, the HD598 is not bad, but lacks the resolution, doesn't quite display audio as natural as the HD650. There are many great and excellent headphones, but myself and many head-fiers, the 650 just fits. I find myself just sinking into these. 

Getting these back again is a real ear opener. They are everything I remembered and even more so. Absolutely (still) world-class. 

If you are looking for a great audio experience and are willing to pay a little bit more than typical price. These headphones are open back, so if you are listening in noisy areas they loose alot of their ability, but in the same light the sound quality is excellent in quite areas. If you plan to buy these headphones then consider using them for home use where you can get to a quite area that you are willing to listen to pretty much just listen to music. Also these headphones are not for everyone, I say this for one simple reason : YOU HEAR EVERYTHING! Literally I was entranced when I first these headphones for a simple guitar riff. Since I play guitar I heard every little imperfection in the note played. But overall these are one of the best headphones that money can buy.

Sennheiser HD 650 
 
COST: $370
 
Background
 
This headphone is well known by many people. With that being said, it is not a "new" model, its been released for a while. It has also been dropped on massdrop as the sennheiser HD6xx, once again returning our attention to the greatness of this headphone. There is also this big question whether they will drop the HD6xx again or not with over 50,000 people requesting it ! 
 
SPECS
 
- frequency response of 10 - 39,500 Hz (-10 dB) 
- High-power neodymium magnets
- Lightweight aluminum voice coils
- 300 ohms 
- SPL: 103db
- THD: less than 0.05%
- Open back
 
Review
 
Design
The headphone is not the stylish headphone but remember these are open back and are intended for home use. It comes in one single silver color although the limited massdrop edition (HD6xx) comes in a midnight blue finish
 
Build Quality
Mostly plastic and the wires can feel cheap but everything works well and most of all comfortable 
 
Sound Quality
Now this is where we talk about the most important thing in a headphone. The sound quality in these headphones are superb. Scratch what you've read from other people because we all have difficulties describing this headphone especially when it comes to the sound qualities. It is the best neutral with extended bass YET still not boring... 
 
Overall is it worth the money?
Absolutely, if you can buy one headphone and you are buying something other than this, you are doing it wrong !
 
AMP/DAC?
yes I highly recommend you use one with these. some recommendations are some schiit products or O2/ODAC 
NOW keep in mind these are "some" and there are countless more others recommend depending on preferences
 
I personally use the DARKVOICE 336SE tube amp with my OPPO HA 2 SE as the dac
 
FEEL FREE TO KEEP THE LIST GOING DOWN BELOW IN THE COMMENTS
 
Mods
there are various mods online that can be done easily to improve bass etc, shoot me a message if you have any questions or difficulties
 
 
SOULSIK LAB SAYS
 
Want me to compare x headphone to these? feel free to message me for extra help ! OR better yet try my pair before you buy them ! HOPE THIS HELPED 
 
review provided by soulsikreviews.com (more detailed review available on the website)
 
video for reference only
 

The HD 650s do just about everything right. Extremely forgiving yet detailed, it makes all music sound gorgeous. Absolutely dreamy, you'll find yourself lost within your music. Much of the sound attributes have been said before, e.g. the warmth and laid-back signature, so all I want to say is that if you ever had to buy a pair headphones solely for the enjoyment of music, pick the 650s. It's an absolute bargain at it's current price.

My only complaint is in aesthetics. If only it would look as beautiful and elegant as it sounds. Although, not really a complaint as the sound takes precedence and it's really not that ugly. Could use less plastic though.

Everything sounds great, extremely clean and extremely detailed on the HD 650.
 
Fantastic clean sound, fantastic resolution, fantastic tone, warm, extremely well balanced, great bass (not boosted), very detailed sound, well separated instruments, very present sound, great sound stage, the highs and mids are smooth, clean and sound very musically.
 
And how about the infamous veil of the HD 650? It, definitely, does not exist. Perhaps on the old models, with the black drive, it could be true. On my new model, with the silver drive, there is absolutely no veil.

Review coming. 

I love them, perfect sound.

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I am no audiophile but I can say that these headphones are the best I have heard while I spent a grueling couple of weeks looking for a good pair of headphones.  I started off with Dre Beats but felt like I squandered my money so I returned them and started looking for a real pair of headphones.

 
The one who started it all, the 650s was a unexpected purchase for me, I was 16 back then when I got the 650s , the only nice headphone I had was the v6 and a cheap Supra Sony but since I was building a nice PC at the time, I decided to invest in some Audio , wanted to get the best ....Initially I was gonna get the hd800, the price wasn't a issue since I had a huge budget but I decided to invest that elsewhere and got the 650s instead, these in one word are my "Favourite" Headphone, love them.
 
To the sound , I always thought the 650s were a acquired taste until I got AKGs, little did I know what I had there
The 650s signature is warm, rolled of yet detailed with a amazing bass extension, as far as dynamics go the only headphone I enjoyed the bass on was the Tesla 1, no other headphone has the 650 bass , control is just exceptional , I have test tones which determine the tightness and the 650s are off the charts , no headphone has performed like them , they also have a great excursion factor ...what that means is that they will never rattle, the membrane will never be over-driven, usually a lot of people call it SPL but not all high SPL headphones have a good excursion factor, usually excursion factor affects low frequencies, Output Impedance can minimize it but not eliminate it, more the control less the rattle but the 650s are extremely robust, these will never fail ...just sensational  

 

 

 
Let's descend this time - 
 
Treble - There is no doubt they are rolled off but ...I have heard the 650s on systems where the treble was right there, with all the detail and presence, would I call them veiled or muddy ...absolutely fuc**** not , they have all the detail, but this roll off can be good for some people who like a relaxed sound, they are just luscious and full bodied , they are never thin . As much as I love the treble they aren't grain-free when compared to Ultra-high end headphones, do I care, again absolutely  fuc**** not, musicality wins. 
 
Mids - If you are considering buying these, I don't need to tell you about the 6XX mids, imagine a sound which encompasses you in it , that's what the 650s do when it comes to the Mid-Range , they have one of the best Mids I have heard, to this date I have to find a dynamic headphone which has the musicality in the Mid-Range like the 650s do, if you know a dynamic headphone which has what I'm looking for, let me know down in the comments. 
 
Bass - The bass man ...I love the bass on these, the extension, tightness and overall sense of impact is top notch, as I said earlier the only dynamic headphone which impressed in the bass was the T1, now of course I know a Planar will kill it when it comes to sub-bass, that metal never rolls off, goes to down 20Hz with a flat line, but these are not a Planar so for a dynamic they are my top headphone, nothing touches the 650's extension and refinement. 
 
Build and Comfort - 
 
I think they are well put together, Senn is the Samsung of Headphones..all plastic of course.
But as I said they are well put together and have the solidity I could expect from a decent headphone. The Headband is plastic with two spring steel rails attaching to the ends.
They can easily be bended to make them clamp less if they bother you initially, I never found the clamp bothersome..at any rate natural break-in is the best of course, my two year old 650 compared to my brand new 600 have a significant difference.
The Earpads are generously padded and are very comfortable, the 650 happens to be my top headphone for comfort, which is a goof thing of course.   
 
Yes of course there are some negative things - 
 
1) The dt880 is more refined in the treble, is much less grainy but again it doesn't have the other tonality edge and the excursion factor is not even close to the 650s. 
2) The Soundstage is not that impressive, a lot of people use the classic term "3-Blob" I still don't know what that exactly means but hey ....The dt880-990 surpass the Senn in terms of Soundstage. 
3) I wish the Spares weren't so expensive, for a earpad I could buy a entire headphone like a NVX XPT100 , not cool Senn !!!!!
 
Some Random Notes - 
 
1) Although these are 300Ohms I find them to be fairly easy to drive.
2) The Stock cable can be easily made balanced.  
3) I would recommend a nice OTL, I am using the Valhalla 2, in a perfect world I could choose SS, like a Violectric Stack or maybe a HDVD-800 but since it's not a perfect world I have to resort to Mid-Fi/HiFi amps which are fine, they still portray the emotion. 
 
I will add more..this is all I can think of right now  
 

 

 

 

 
So yeah, love them to death 
I don't think my opinions will change until I get a 007 from STAX, till then I will enjoy the mids on my 650s 
The comfort is excellent and so is everything else , if you want some of the best dynamics in the world get the 650s , they will surely make you smile , it doesn't matter if you have the best of the best setup, if it doesn't make you smile, it's a waste of money, take this analogy .....Upgrading a BMW 328i (F30) to make it faster than a RS5 is more fun than getting a RS5 , of course a RS5 is a RS5 but it will not make you smile as much as a upgraded F30 will, that's what the 650 is for me .....a must have headphone, take it easy folks, my Video Review will come in 2 days. 
 
Video Review - 
 
 

I'll try to be brief here, which is nearly impossible for me to do.
 
I bought this headphone last month and previously had two pairs. Those pairs had really anemic upper mids and had bloated mid-bass. This pair does not. I even used my old reference tracks I tried previously and this pair has a quite balanced sound signature. Not dead neutral or completely uncolored, but I would say it's just smooth sounding. Possibly one of the most musical headphones i've owned.
 
This headphone for me makes a lot of my crappy recordings that are harsh and fatiguing a bit easier on the ears. I don't ever get bombarded by treble or anything else. No shouty vocals or whatever else. It also doesn't make any very warm recordings worse by making them sound congested or less clear. I've found that they also seem to have better bass extension than my HD-600. Punch me if you want, but the bass on THIS HD-650 seems more controlled than that of my HD-600. It's closer to the bass quantity of my HD-580 (same driver I know).
 
Despite being very forgiving for bad recordings (only the garbage with the mids/treble cranked to max in the studio) it still need higher bitrate files. You can still tell the difference between high quality recordings and bad ones despite being both in FLAC.
 
These are very detailed. Nothing is missing, but all that detail is not shoved in my face. As hard as it is to believe, my DJ100 and HD-650 benefited more from my ODAC than the Q701. No idea why. The HD-650 seemed to become more revealing and detailed. The Q701..not as much.
 
This is a good headphone for when I just want to listen to my music and not be bothered by recording flaws. I can listen to these all day without fatigue.
 
The soundstage is better than that of the HD-600/598 IMO, but it's not larger. Better imaging etc. I think the ODAC is playing a role here too. Never thought such an improvement was possible unless my ears are playing tricks.
 
The sound is nice and full sounding, but not excessively warm. I thought I hated warm sounding headphones, but now I guess not.
 
This pair also doesn't seem to have sucked out upper mids, but at times there seems to be a very slight peak. Maybe a tiny one. I know this goes against what nearly everyone says. This pair also doesn't seem dark. The treble is very good and not lacking. It has slightly less than my DJ100.
 
Despite making my bad music sound a bit better than it should be, it still is quite accurate to how the recording is..sometimes. You often don't realize how bad the recordings are until you switch to a different headphones such as the KRKs, DJ100 or Q701.
 
I gave it a 1/5 for value. It's worth $400, but $500 is nuts! My $80 DJ100 with the same setup isn't that much worse and often even better in some areas. Both have some similarities. The DJ100 just has slightly more forward mids and more treble. DJ100 has better low bass. Sounds a little clearer too sometimes. Both are now my top 2 favorite headphones.
 
This review might be off the general consensus, but I don't care. This one is much more balanced than the others i've heard.
 
Setup was Headroom Micro Amp (not a portable amp an drives it with ease) from ODAC. I always use FLAC files. I previously used the Asgard with the HD-650, but found the Micro amp way better.
 
BTW this is as close to my DJ100's sound as I could find. My DJ100 sounds like a weird mix of an HD-650 and maybe a Sextett. Maybe the 650 and another AKG. The DJ100 is definitely a little more forward sounding, but still smooth sounding (with my setup, which I think is very neutral). I only mention this because I always wanted an open headphone that had some similarities to my DJ100.
 
NOTE: if this was priced at $350 retail it'd definitely get a 5/5 for value.
 
If you're curious I'd rank my Sennheisers as:
HD-650 > HD-580 | HD-598 > HD-600
 
Weird, I know..not a ton of difference between the 580 and 600. 580 just sounds better than the 600 to me. Clearer and with slightly more forward upper mids and maybe less bass.
 
Strange as it sounds, I tend to prefer the AKG type sound, but the HD-650 is just addicting.
 
EDIT: The only change after use I've noticed is that the lower mids smoothed out a bit. Out of the box they were a bit "shouty". Kind of like the PX100-II (for me) without an amp.
 
I also think it's a mistake to do many A/B comparisons of these headphones with something that's dramatically different (like a flat studio monitor). With crappy recordings the HD-650 will always sound better and it's easy to be fooled.
 
Oh yeah.. I also use these for gaming! 40 hours into Dark Souls and even use them for movies. The HD-650 can't match the soundstage of the Q701 though. HD-650 is obviously much warmer and a tiny bit bassier.

Setup for review
1. Dacport lx
2. Scsag m2m
3. JD's O2

Review

When i put them on for the first time i could really tell that this HP has some nice comfort on it, even though the earpad kinda hard at first..

I start to feel fatigue after 2 hour of listening session, this fatigue feeling is very hard on my left ear, but after 1 weeks of use, this feeling is gradually reduce

As for the sound itself
I don't feel any veiled things like many people said, the vocal is really clear and quiet laidback, allowing each instrument to produce their sound independently.
The next great thing that i feel is the bass that have a nice "grand" feeling, it's feel very differently from my previous HP which is dt880, on dt880 the bass is punch deeply, but doenst have those grand feeling like this HP, the smoothness of it's high frequency also give a nice long session listening with no sibilance (or maybe a little)

As for the sound stage, the dt's allow you hear more deeply, like it was more isolated, but the hd650 is also gave enough staging as you can still feel each location for every instrument

Everything sounds great, extremely clean and extremely detailed on the HD 650.
 
Fantastic clean sound, fantastic resolution, fantastic tone, warm, extremely well balanced, great bass (not boosted), very detailed sound, well separated instruments, very present sound, great sound stage, the highs and mids are smooth, clean and sound very musically.
 
And how about the infamous veil of the HD 650? It, definitely, does not exist. Perhaps on the old models, with the black drive, it could be true. On my new model, with the silver drive, there is absolutely no veil.

These are simply the de facto best headphones at this price. They have a dark, slow sound that's suited to strings, guitar and vocals, and their matched drivers mean that centre-stage vocals will actually come from between your ears.
 
These don't so much break in, rather you get used to their reproduction. I can't recommend these enough, and everybody should spend some time with these, whether they take to them immediately or not.

I bought these headphones on December 2011 and have since been thoroughly using them. I am absolutely happy with my purchase and here is why:

Pros:
- Fantastic sound, albeit a bit on the darker side (amazingly natural mids, and poignant lows with controlled highs)
- Amazing bargain at $300, as the sound quality is truly unbelievable
- Extremely comfortable to wear for long hours
- Fares excellent in general use

Cons:
- Requires a powerful amp to reach its full potential
- Build quality and design are average

Use to think the HD600 was the best. When connected to my Asus STX  it is better then the HD650. (March 16, 2017 update)
 
Then I bought a Dark Voice headphone tube amp from Mass Drop. The dark voice is so much better with the HD650. Rolled a few tubes and the HD650 sounds excellent. The HD650 really does scale with your equipment. I do not even listen to the HD600 any more. With the dark voice the HD650 is smooth and crystal clear but you also know you are using an analog sound. There is no "dark veil" with the dark voice.
 
 
I have:
SR-60, Sr-80, HD555, HD595, HD600, HD650, AKG Q701, Bose QC 15, ATM-50S, Ultrasone HFI-780.
Least favorite: HD555 (boring and Muddy) and Ultrasone 780 (Sharp and shrill-Maybe needs more break in)

Just got a pair of these for Christmas and have to say that I was very impressed with the box they came in, very solid packaging, and neatly organized cord. There is a 3.5mm adapter included in the box, something I was not used to coming from a pair of Grado SR225i cans.
The build quality is very good, I don't feel like I will scratch or dent them without a decently high tumble. The cord is detachable and feels like it will not likely give out anytime soon.
As for comfort, I never really found my old Grados that uncomfortable (I know you guys/gals on Head-fi and reviews on Amazon always talk about Grados being uncomfortable) but now I can hardly wear them after having used the HD 650s. It is a very comfortable fit once you get them adjusted nicely to your head.
As for sound quality, I play everything in FLAC or MP3 @ 320kps using Foobar2000 with the kernel streaming plugin.
Due to the fact I don't have my Maverick Audio TubeMagic D1 Plus Edition in yet, I have been trying to use the 3.5mm jack from my laptop to listen to music. The HD 650s don't sound very special through that source at all, they are very boring when plugged up to my android phone as well. I almost picked up my Grados again just until my amp came in, but I just like the feel of the HD 650s so much more.
I eventually used HDMI out from my laptop to my harman/kardon AV receiver along with Foobar2000 w/ WASAPI (manually selecting the receiver in the output list) and plugging my headphones into it as a source. This made the headphones sound much more worth their money and really blew me away.
Music I tested included Pink Floyd, The Beatles, Led Zeppelin, Daft Punk, OutKast, The Chemical Brothers, Kanye West, and Fleetwood Mac. I heard details in Time by Pink Floyd I have never noticed before.
I am very excited to get my Maverick Audio TubeMagic D1 Plus Edition in. My library is waiting for me to listen to everything over again.
If anyone wishes me to report in how the D1 sounds as a source for these cans let me know in the comments.