These are not headphones per se, more like a medieval head torture chamber than plays sound. Unusually, it's not the clamping force on the sides that causes issues, but on top. The headband is not shaped to fit human heads, but rather one of the square flat heads that the sentient humanoid robots that make Sennheiser products have, I guess.
 
The sound... how would I describe it...
 
Lethargic? It's not neutral, if that's what you're thinking. Rather clinical sounding headphones. The mids have strange prioritizations and the bass leaves something to be desired.
 
Sub-bass: Decent amount of extension
Upper bass: a crater exists on the frequency curve where this would normally be in a headphone.
Low Mids: This is my biggest issue with these. The low mids are very shy on these.
Upper Mids: Overemphasized. Good detail, and smooth, but they get too much priority for my taste.
Highs: reasonably detailed,  not sibilant. Agreeable.
 
The nice thing about the older models of Sennheiser is you can probably find an insane deal on a used one somewhere.
 
I wouldn't bother though. This Sennheiser design is ancient, and it lacks many creature comforts that you can get even for $90 now. The giant curly cable is non-removable for starters, so it's not a good portable headphone, despite the great isolation it gets.

While some may think Sennheiser headphones are "ugly" or "dull", cosmetics are nowhere even close to being on my list of have-to-have's. Even if it was on my list, I quite like the look of the HD280 Pro. It's a no nonsense design that brings about a feeling of confidence in it's durability. The HD280 Pro was designed with function in mind, not fashion. If you're looking for something pretty or shiny, this a'int it (by the way...a'int a'int a word).
 
The audio cable...oh the audio cable...it's pretty much what I had expected with my last purchase. While it's technically not "removable" it's much more substantial, not longer than necessary , and it's coiled so it's much easier to stow away.

When I say technically not removable, I mean you can't simply pull the audio cable out of the unit like the HD380 Pro. Instead, if you do damage your audio cable, you have to open the ear cup and do some light wiring to replace the audio cable. In fact there is a guide in the manual that shows you how to do so. To some this is unacceptable, however I'm just fine with a thicker, more durable cable that is more resistant to breakage in the first place.

I'm not going to lie to you, these headphones have a crazy amount of clamping force! So unless you have a small-ish head...oh who am I kidding, even if you DO have a small-ish head, you're going to want to break these in. I've read that some place them onto a basketball or volley ball to break them in and reduce that clamping force a bit. Otherwise, you'll find it difficult to use them for extended periods of time. As durable as these are however, be cautious when breaking this in, as the construction is mostly plastic which has it's limitations as far as how much flex it can handle. Before they were completely broken in, I've had to take breaks from several editing sessions because of a pressure headache caused by the death grip these things have on my head. The reason for this clamping force is in order to aid in noise cancellation or attenuation. According to the specs, they provide 32 decibels (dB) of attenuation.
 
They are pretty good at blocking out noise. While they won't block out my dishwasher which is about 10 ft from my desk, they do block out a considerable about of noise, such as people talking, the TV (as long as the volume isn't cranked too high) and general ambient noise. So far these have been great for when I'm video editing, or just want to chill and listen to music or watch YouTube video with less distractions. My darling fiancee will often have to physically signal me with a wave to get my attention, or come distract me with smooches...which I'm really OK with actually.
 
I tested these headphones with various types of music, hip-hop, rock, acoustic, metal, and even some EDM. I did notice that the HD280 Pro provides a good bass response, when good bass is present. It doesn't do any fancy bass boosting or anything like that, which is good because it allows me to get a more accurate perception of my source audio. The HD429 seemed to give a slight (albeit smooth) boost to music tracks, which is no way was a bad thing, just different. The HD429's slightly elevated bass response is better suited for casual listening, whereas the HD280 Pro is intended for monitoring. For that reason, I'm using the HD280 Pro as my main headphones for the home office, they help me monitor my audio levels in my video editing, which is something I'm becoming a stickler for.

I'll wrap this up by saying I am not an audiophile by any means, nor claim to be! Also, everyone's ears are different, and therefore each pair of headphones will sound different for each individual. The best way to see if a pair of headphones are for you, is to have your ears decide, don't let anyone tell you which product is right for you.

 I'm not an experienced headphone enthusiast so there could be better product for similar $$ but I would think any difference would be spiting hairs sound wise or preferences  I like the Senns sound anyway .
 
After trying a few  sub $200.00 phones in the stores on  crappy sources I decided these HD 280's were pretty good sound and construction for the  $$$ . The one caveat being they clamped a little tight for a good  while but have settled in now and you can wear these all day they are pretty comfortable and very light with superb closed back isolation ......I don't need heavy stainless or wood bling it ain't my thing I can't see them when I'm wearing them anyway and I don't have or want a big headphone collection on display .
 
 
I've had these about 3 yrs now and they are durable and still look and work as new except a lot better than out of the box . Normally I think a lot of audiophile break in stuff is snob audiophile  nonsense (especially electronics and cables ) but not on these phones or some speakers I've owned it's plausible and definitely improved these phones in a big way but it took a good while well over 40 hrs  maybe a few hundred ? .
 
I just received my entry level Schiit Magni amp from Amazon Prime today and it's a significant upgrade over my Xonar DGX PCIe d/sound card headphone amp in this room . These play nice with the new Schitt and the HD 280's can get real loud on the new amp
 
 All the things like treble ,midrange  extensions  ,resolution,instrument separation perceived soundstage depth etc.  are a lot better then the DGX d/sound card  and it ads a  little extra "pop" for vocals and percussion the the only caveat here is the low bass and impact bass are  lower on the Magni 2 than the Xonar DGX but not a deal breaker at all  so far.
 
 
Definitely play these HD 280's at least on an entry level Schiit Magni amp or something like that . HD 280's can use the extra mW and headroom for dynamic peaks ,clarity and impact you can't get out of onboard PC audio or most PDP's and d/Soundcards.
 
The Schitt Magni output power is rated at ~ double the Maximum for the HD 280's 64 ohms so it's a good pairing  IMO 
and it compares well with the uber clean studio interfaces here in the another room up to a fairly loud point where it starts distorting but it can go louder also ...a lotta bang for the $. 
 
 
I'm thinking of the matching Modi 2 or Modi 2 Uber  USB DAC  to turn The Magni 2 into a modest Schiit stack * ONLY if the Modi or Modi 2 uber are worthwhile additions sound wise from what I have now which on paper at least is open to discussion at least aside from the DAC ASIC (and it's implementation ) anyway  IMO but I'm also inclined to use a clean studio interface I'll be trying this amp on one of those here in another room here and on some other phones in there .
 
 
...for example by professional design my THX pm3 Certified reference 2.1 audio system power  amp we chose is rated at 850 Wpc RMS to feed my THX pm3 certified professional large midfield  12" 3 way JBL's that probably can use half of that tops or much less usually but that combo  can make a snob audiophile cry in a good room especially with the two powered reference subs in there but it was many $$$$  thousands with all the studio gear,Midi controllers a stout  PC and d/GPU and production software and VST's  and aside from the gear the dedicated construction for all that  where it lives here will buy a  nice 3 bd house in some parts of the country . I'm a  believer in amplifier headroom having been an expert enthusiast prosumer for over 40 yrs. 
 
 
 
I'm still using the Xonar DGX outside of the DGX headphone amp for a source for lossless 16 and 24 bit music from my HDD or Tidal Hi Fi 16/44  until I'm convinced a separate DAC like the Schiit Modi or Modi Uber  is a worthwhile upgrade from what I have now but I'm also inclined to use a studio interface.
I'll be trying this Magni 2  amp and HD HD280's  on one of those pro interfaces here in another room  and on some other phones in there .
.............More on that subject  :   http://www.head-fi.org/t/642401/comparison-and-review-magni-modi-vs-o2-odac/435#post_12373795 
 
 I would look at these for an entry level product into the Senns sound ....................
 
FWIW 
I'm not immune to serial upgrading any of my pursuits like homes ,  PC's ,vehicles and 2.1 audio in a dedicated acoustically treated PC Game/Music studio to THX PM3 Certified reference levels currently ,3 TV's in this room  in 4 yrs up to a new 2015 Sony XBR 4K WCG  HDR TV set now ( it's da bomb) and an arguably very decent  64f8500 Samsung Plasma out frt and years of being a motorcycle /vehicle and salt water powerboat gear head ( and professional gear head ) and amatuer audio enthusiast for over 40 yrs .........Obviously I'm just starting on phones here so outside of phones I know the upgrade drill and the law of diminishing returns all too well ☻

Had these for a few months. Not "burnt in", though I'm not sure they need it. According to some, they do. I personally found these didn't have the deep bass that they're famous for, not bad, but not basshead worthy

I've owned two pairs of these over the last 10 years (one channel on the first pair died) and I've used them without an amp or any knowledge of audio electronics. Essentially, they were the first pair of decent headphones I've experienced prior to entering the world of HiFi only recently.
 
The ones I've owned were 64 Ohm but performed admirably at >80% volume on most audio sources. They improve noticeably with a headphone amp.
 
Sound
 
This is a bass heavy headphone and is well suited to movies, action games, and bass-heavy music genres. Bass-heavy electronic and hip-hop tracks are like personal earthquakes with these headphones. Having said that, bass can get muddy on certain tracks if volume is high. Mids are recessed and treble is usually clear with some occasional harsh/shrill-ness depending on the frequency. I'm into classical music and these don't do as well for violin and piano sonatas and concertos due to less pronounced mids/highs and a lack of soundstage (these are closed headphones though). Overall, the sound is great something that is <$100.
 
Construction/Aesthetics
 
These are not particularly attractive headphones nor are any of the structural components high-end (no metal used on the body except maybe the core of the head band). My first pair broke even though it rarely left my house and I took very good care of it. The second pair has lasted much longer so this may be an individual issue between pairs. The collapse-ability of the headphone makes it more portable than most over-ear headphones, which is a plus.
 
Definitely recommended as an entry-level bass-head can.

My comprehensive review of the Sennheiser HD 280 Headphones

 

BURN-IN TIME -   Took about 3-4 days to burn in so maybe 12 or so hours for me

Upon receiving these as a gift for my birthday (so I paid nothing for it). But as of December 2014 it's usually around $100 US - $125 US as far as I know.
 
So I plugged this into an iPad Mini Current Generation (Before the newest iPad Mini with the touch home button) and listened to everything you could think of.
 
-Ambient
-80's new wave
-Ambient Synth
-Electronic
-Hip Hop
-Orchestras
-Jazz
-Classical
-Dance
-Headphone Quality Tests
-Movies 
-Voice recordings

etc.                                     ||

                                           ||

Overview of everything V

 

SOUND - 9/10

LOWS/BASS - The sound overall was great, the lows were clear and not overbearing, the bass was punchy and was pretty fun so much so it made me smile.
MIDS - No real issues I found nothing, it merely just isn't the main factor for this sound signature.
HIGHS - Sigh* This was a bit of a disappointment for me, they are just weird and a bit bright. But it's there nonetheless and not really a deal-breaker.
 

COMFORT - 9.5/10

These headphones are low profile, not so much so that I don't notice them but close. I have about medium-sized ears and they fit quite fine with some room to spare.
Due to it's signature Sennheiser cup shape, these things aren't falling off. I took these things to work and had them on from about 8:30 or so to around 2:30 and I was fine.
Granted this may not be the same for everyone and pleather pads are not my preference. I much prefer plush ear-pads more. But I had no real issues with these.
Another thing to note is the cups themselves, they move and rotate every which way and are comfortable on my neck provided the pads themselves must fave outward and pads cannot kiss when on 
my neck. But great nonetheless
 

BUILD QUALITY - 7/10

 These headphones are sturdy and rugged, not to mention low-profile in general both aesthetically and in wearing it. As for the foam headband I must say I have no problem, simply the material housing it just peels off and falls apart which really sucks. The plastic material is...well...plastic but still thick and rugged but not bulky or too big to take with you on the go. 
The coiled wire was a bit of a turn-off initially but given it's thickness (but not too thick by any means) has held it up to this day. The headband itself under the plastic shell is metal I've heard and I believe it, it holds up and is tough as nails. This thing overall is beautiful to look at and is built like a tank.
 

OVERALL EXPERIENCE / FINAL VERDICT

So having these cans for about a month or so I can say that these headphones are pretty solid. Sound amazing for the price with the exception of the highs being a bit bright. They were comfortable and had no issues overall. But given the HD 380 pros are just a few bucks more I'd recommend those as they fix any of the problems I had.
 
Pick them up if you can't spend $150 for the HD 380's
 
-GALVA

The Sennheiser HD280 that I'm reviewing do not belong to me, they're presumably a couple years old (I didn't ask) and in good condition aside from a couple scratches on the earcups. I was curious to how they sounded, especially in comparison to the HA-RX900/700, ATH-M35 and M-Audio Q40 (all of which I don't presently have but definitely remember quite well). I do have Sony XB90EX, Fostex T50rp II (modded to be flat aside from a spike at around 8 - 10 khz) and MDR MA900. All very different headphones, but yeah on to the review.
 
Build Quality: 4/5
These are solid feeling headphones, the cable seems nice but I suspect it's on the cheaper side due to the fact these insensitive headphones have an audible whining similar to the Q40's stock cable, which I know for a fact is awfully cheap. I like the way the earcups swivel, all the moveable parts seem durable. (the 4/5 is because the cable quality, most certainly).

Comfort: 3/5
These are light headphones with poor weight distribution and strong clamp. I get a mild headache-like feeling from wearing them for about a minute, and I'm used to ridiculous clamps (hint hint, Q40). The earpads are deep, however they're not well padded and don't feel that great with the strong clamp, but I'm not very sensitive to this kind of thing so it's fine for me. I know a lot of people would find these dreadful to wear, but I suspect the clamp helps with the isolation which is decent. At a lesser price, both the RX700/900 and M35 are much more comfortable, though the RX700/900 has a somewhat awkward fit and the M35 has weird pressure points, neither are as uncomfortable as the HD280.

Price-to-Performance Soundwise:
The HD280 is a mixed bag of nuts, for sure. I've been listening to them for a few hours and have adjusted to their signature pretty well (all my headphones have pretty different signatures, so this is no problem for me). Plugged into my Sansa clip+ these sound almost exactly like an RX300/500. (15$ headphones with very mediocre sounds, but acceptable at their price). The cable noise isn't at all present with the Clip+, but the headphones sound thin and slightly less refined in the lower frequencies with an oddly out of place and thumpy subbass which seems to come from nowhere. I think it's more accurate to say they're an inbetween of the RX500 and 700, leaning closer towards the 500.

My source and amp is the Schiit stack Magni/Modi, and with it the 280 sounds a tad better, but the cable creates a background hiss which is quite annoying. For a proclaimed 'monitor' headphone, the subbass is a bit too pronounced and a tad uncontrolled, but not as bad as you'd expect.The bass lacks texture big time, but it gives the headphone an illusion of a fuller sound. The treble is rolled off quite a bit after 10khz but before that there's a noticeable peak that makes it sound bright/harsh. The upper midrange is very recessed too, making vocals sound muffled and murky in comparison to the lowest midrange and upper bass. The soundstage is oddly wide, but it sounds almost as though it's artificial, like encased by a plasticky sounding barrier. Soundstage lacks depth and height, being purely left to right and wide. Pleasant lack of midbass hump, which the M35 have but not extremely so --- however the subbass emphasis is more distracting in a way. The overall clarity and imaging of this headphone is mediocre, even if the soundstage is big I have trouble picking out details. The M35 has a smaller soundstage, but it outdoes the HD280 easily with detail delivery and imaging. Comparison to my MA900 isn't necessary, as the difference in quality is just that large. While the HD280 doesn't sound awful, it should NOT be used in any kind of studio. It's not flat by any means, recessed upper mids, big treble-roll off and some subbass emphasis make it a poorly coloured and undetailed headphone. Both the M35 and RX700/900 sound better, objectively and subjectively. RX700 is actually the superior of all three, even though it's priced at a mere 30 - 40$ about half the price of the HD280 and the M35.

Direct comparison with my T50rp II (modded) (a large amount of fiberglass, a little cotton and clay loaded baffle plate with 3mm ports on the vents. Also, I use Alpha Pads with it and I've covered the 'reflex dot' or whatever it's called (pardon me if I'm wrong)). Ten songs:

Bassotronics: Bass, I Love You
HD280: Bass is audible, doesn't go very deep. 
T50rp II: Bass is more subtle, can't really tell how deep it goes because it's hard to hear over the rest of the song.
 
Bonobo: Jets
HD280: I kind of like the way it reproduces the female vocales in this, but the imaging gets a little blurry when the background instruments play alongside it. It's hard to hear the details in the background, and the harp sounds a little dull. The synths sound pretty good, though --- the subbass has a bit of authority behind them that doesn't blurr with their midrange frequencies, probably due to lack of midbass emphasis.
T50rp II: A little bright sounding in comparison, bass isn't too different but it lacks a sense of bloat. The synths in this sound similar to the HD280, but lack the subbass boost and sound a lot cleaner as a result. Details are very easily picked out, though the soundstage isn't that big (it's at least bigger than the 280's) everything is there and easily defined albeit a bit on the bright side.


The Dirty Heads: Stand Tall
HD280: The overall sound is a bit dull, but wide. Guitars have a rounded quality, almost as if they're a beginner guitar you got at a pawnstore for a 20$. Imaging isn't that bad in this song, but the background singers can sound really blurry. Treble sounds etchy, almost like the song is of a really low bitrate (such as an 240p youtube version) and the drums sound off in this song. Vocals sound alright though.
T50rp II: Immediately I noticed the huge difference with the bass guitar, much more texture and it blurs a lot less. Vocals sound good, less thick than the HD280 and a bit more realistic. Drums are excellent, sharp and natural sounding -- I can almost hear the acoustics of the room it was recorded in in the way the drums sound. Background singers don't blend in with the other instruments, so that's good. 

Excision: 8 Bit Superhero (Eptic remix)
HD280: I can't say the HD280s belong here. Soundstage is really small and the general sound is very bland, the only thing the HD280 does right here is the subbass. Everything sounds muffled.
T50rp II: Switching to the T50rp II I immediately notice all the sounds that sort of blended together. You can hear the electronic sound and all it's texture with the T50rp II, but it sounds a little thin. The bass is less quantiful but extension is better and it also transitions to the midrange a lot less strangely than the 280.

Flux Pavilion: Hold Me Close
HD280: I like the way the HD280 sounds here. Soundstage is about right, good sense of wideness without much blurring into the middle like it usually does with other songs. The subbass quantity goes well with this song, but it sounds kind of funky considering the hollowness of the rest of the spectrum. I notice that the HD280 seems to have pretty bad decay, this song makes it easy to tell.
T50rp II: At first the sound is a tad on the brightside, but the midrange sounds excellent with the synths here. Vocal samples are really smooth and realistic, well as realistic as they can be in this kind of song. Bass is good as always, a little shy in quantity but good nonetheless. Overall clarity is top-notch, but the treble sounds a little too smooth, but it's probably just the way the song is.

Jack Johnson: Crying Shame
HD280: The 280 trashes the vocals here. This kind of sound just makes me feel like I'm listening to 20$ headphones, and not very good ones. Treble is a bit grainy, also is kind of similar to sifting sand. The drums sound really dull, like someone covered the heads with cloth or something. Bass guitar sounds relatively good, has plenty of authority and sounded and sounded well controlled, still not much texture though.
T50rp II: Wow, just wow. This isn't the same song, ist it? Vocals are super smooth, though you can easily pick out the artificial reverb-ish effect added to it. Drums are tad bright, but they have a nice clean sound with good impact. The bass guitar is a lot less pronounced, but it's got excellent tonality.

La Roux: Tigerlily
HD280: The vocals sound alright, but everything else seems to lack dynamics and sounds really flat. The various sounds kind of blend together and overall this song is muffled sounding. The bass has a nice impact and visceral quality in this song.
T50rp II: The vocals sound really close to being thin, but it's more like they're very neutral sounding. They sound a tad further back then the HD280s, which seemed to place them really close to you. The song itself has an interesting crispness, bass is a lot subtler and lacks impact but when it hits it makes you feel like it's really low. 

Pink Floyd: When the Tigers Broke Free
HD280: The 280 portrays the large sound of Pink Floyd quite well in this song. Vocals sound somewhat raspy/nasally(?), but don't sound muffled. The subbass emphasis makes the drums sound huge and powerful in this, but the sense of space is ruined by the higher drums sounding so unnatural. Things get a tad congested towards the end of the song, but not horribly so.
T50rp II: You can hear the quieter details more easily here, the main vocals are a touch too bright for my likings. The big drum in the background doesn't sound as big as it does on the 280 but you can hear the springiness it has after impact, the background singers are also more easily heard and you can almost pick out different voices. I also noticed a couple instruments in the background than I did with the 280, and the sense of space here is huge for a closed headphone.

Kanako Itou: Space Engineers / 宇宙エンジニア(uchuu engineers) (orchestral version)
HD280: Kanakou Itou's voice sounds a bit muffled here, as well as the instruments but not as bad. Compared to other songs, the soundstage and dynamics are really squashed sounding. I could try, but I don't think I could ever enjoy this song through these headphones.
T50rp II: Instruments sound a tad tinny but the sense of space is huge and the stringed instruments have a crazy amount of texture. Kanako Itou's voice is rendered really well, not as realistically as the MA900 (woops, didn't mean to throw that in but it is my standard for naturalness) can portray it but good nonetheless. The instruments in this have a really nice attack and the dynamics are compared very well in comparison to the HD280. This song is hard to get to sound right, neither headphone sounded natural here.

Michael Jackson: Leave Me Alone
HD280: The 280s lack of treble is pretty clear on this song, it sounds a lot like an old car stereo here. There's a decent sense of space, not much detail blurring. Bass is probably the best the 280 does in this song, probably because there's not a notable amount of subbass and the 280 is pretty modest with it's midbass. At this point, I can't really say much that hasn't already said about the 280 in all the other songs. 
T50rp II: I expected the T50rp II to be really bright here, but surprisingly it was only a little bright. Michael's voice seems about right, the soundstage in this song is pretty small so it sounds a little closed in. Something about the T50rp II bass has a subtle impact and speed which makes this song oddly engaging. Like the 280, not much else to say at this point.

Summary of HD280 vs T50rp II (modded) comparison:
My T50rp II is a good bit brigther than the 280 and lacks the severe rolloff the 280 has, making is a little harder on the ears. The 280 is extremely unresolving in comparison, and despite not being bright and a little bass oriented it still sounds like a very dull and lacking headphone, especially at the price of 80$. A modded T20rp II would be a much, much better value than an HD280. I honestly don't think I could ever seriously recommend the HD280 to anyone, it's most positively feature is it's build and that can only get you so far.. the JVC HA-RX700 is a far better alternative at a far lower price, for those who're concerned. For those deciding between the HD280, the M35 and the V6/7506 I'd very seriously recommend either of the two latter, even without hearing the V6 I know it's at least slightly more detailed than the M35 which ultimately makes it very clear in comparison the the HD280. I'm sorry owners of the HD280 who enjoy it, it's a very poor headphone at it's pricepoint and I wouldn't pay even 30$ for it. I didn't really mention the XB90EX much, but despite it's elevated sub, mid and upper bass (by 6 decibels) it still manages to deliver more clarity than the HD280, costing only 20$ more and being a bass oriented IEM I think that's just ridiculous. ---- disclaimer, I don't believe in physical burn-in much, but mental burn-in is a big factor so I made sure to give the HD280 a good few hours of listening time before deciding to review it. At first listen I literally thought it was identical sounding the the RX300, with added subbass. After a few hours it got closer to the RX700, but that's a generous thing to say. I'm dissappointed, this is the 2nd sennheiser product I've tried and I don't think I can appreciate a company that places no value in it's lower priced products and don't think I'm interesting in buying any of their other headphones, --- which generally have a reputation for being overpriced anyway.






 

I like these headphones when I know that I'm going somewhere where I wouldn't dare to take one of my more delicate headphones (e.g. Sr225is's). The primary reason being that they have never once fallen off of my head. Honestly, that's nearly all they've got going for them (aside from the OK base that comes from the excellent seal between your head and the cans when used with an OK amplifier).
 
The sound is otherwise lacking in low end, and the mid end is dry and somewhat overwhelming.
 
 
Other than the OK sound-stage an the bass (it plays hide-and-seek), there's not much worth mentioning.
 
Listened to:
- Pink Floyd - Money : The guitar line at the beginning was clear with resolute drums, but as components were progressively introduced, things began to get messy
- Gentle Giant - Just the Same : Things began to get muddy (There's a lot of texture in this track)
- Butthole Surfers - Human Canonball : Guitar was tepid
- Anne Bisson - September in Montreal : Bass was somewhat hidden, vocals were clear, but lacking overall satisfaction
- Bela Fleck (& Flecktones) - Blu-Bop (From Flight...) : Piano was somewhat hidden by the guitar
- PTX - Aha! : Low-end vocals were not easily discernible. Mid-end took the stage. Only voice with discernible timbre was mid-end.
- Mike Doughty - Monster Man : Bass was too present this time. 
- Mike Doughty - Super Bon Bon : Vocals were clear, the whole mix sounds OK, with the exception of the guitar samples (especially alongside vocals).
- (Pierre Moerlen's) Gong! - Time Is The Key : Finer details were hard to make out.

I've owned these cans over 2 years and I've watched them mature like fine wine sitting in the barrel. When I first bought them I was surprisingly disappointed. I was expecting a lot more but found their sound to be tinny and weak. After many many many hours of burn in these cans really warmed up and showed coloration in a nice way. I like to compare these headphones to my DT880 600ohm cans for reference of sound. These cans are much more LIVELY while my DT800's are more ANALYTICAL and neutral. I would say the HD280s are much more suited to electronic/hip hop/ dubstep and any sort of bass heavy music that doesn't require a soundstage. I found my DT880s much better for rock/jazz/some electronic(progressive house) and a few other genres that require a large soundstage such as live performances and movies.
 
Overall, the HD280s take a long long time to burn in. I suggest burning them in for atleast 200 hours to see the full potential of them. These cans are an amazing steal and have incredible bass response for their price tag. My source right now is an HT Omega Claro 24-bit/192khz DAC to a Schiit Magni amp which sounds absolutely amazing. I prefer my HD280s for reggae and hip hop over my DT880s but would pick the DT880s for just about every other genre of music.
 
Here's the bottom line: let these cans mature and then they will put a WOW on  your face. I have compared the bass of these cans(500 hours burned in) to the Ultrasone Pro 900s my friend owns and I must say these can hold sub-bass frequencies surprisingly well while sitting next to the bass king Ultrasones which still reigned supreme over the HD280s.
 
For $99, I purchased them at discounted price for $78 I must say they are a complete STEAL. BUY THEM! NOW! If you have money to splurge I suggest you get the Ultrasone Pro 900s as they will crave your desire for BASS

 
[size=13.0pt]The first of these that I have are going on 5 years old, I am also listening to them while I type this review. I am basing my opinion on this pair. I received a NIB pair about a month ago but have not listened to them yet. I really like everything about this headphone. I am a big fan of the Sennheiser sound signature though; they always seem to suite my musical tastes. I have a preference for closed cans, and this is a solid one for an entry level of better sound. My one complaint is that I have a large head and have to extend the headband all the way out on both sides. This is where my complaint comes into play, with them in full extension and on my head, the band sticks out weirdly from my head. It is an almost comical the way it looks. Other than that I cannot fault these cans.   [/size]

I'm a pro-sumer, not an audiophile, so I will not discuss the sound, really. These were purchased new, are still stock, not modded.
I have owned these cans for 2 years, so burn-in is complete. Full head of hair, no glasses, no TMJ.
 
Pros:

1. completely circumaural, even for my large-ish ears leads to great noise isolation. I keep the volume below 20% and can hear the music fine and no cube-mate phone calls.
2. Nice padding on cups and headband. I wear these for hours at a time at work and neither the clamping force nor the weight of these bother me.
3. Both cups rotate and swivel. You can wear them comfortably around your neck or off the ear of choice easily. They also lay flat and fold into the familiar headband ball.
4. The sound is pretty good for the price.
5. Single-sided cable entry (left side) with nice, thick coiled cabling.

 
Neutral (good and bad even out):

1. Plastic construction throughout. Seem a bit flimsy, but this also makes them light. I have had no problems with cracking or creaking

 
Con:

1. Fixed cable. I would use these for the bus commute but the cable is way too long and heavy. (In my opinion this is the only thing that keeps these from being viable portable headphones.)

 
If you buy your gear new, these are going to be a pretty good purchase, especially if you wait for a Black Friday sale. If you are willing to try used these may not be your best option as you can find the Sennheiser HD 380 used for about $20 more than these used. The HD 380 headphones sound much better, have metal components, and a removable cable, and possibly come with the stock carrying case. A much better deal.

First, let me start by saying I am a total noob. These were my first and still are my only pair of real headphones. Now that I look back, I probably should have bought the ATH-M50S considering what people have said about it. These cost somewhere around $120 when I bought them. I have had them for a few months and just got an amp (Pyle PHA-40) today (great amp, by the way). An amp is HIGHLY recommended. It got rid of any harsh, screechy highs typical of my computer's headphone jack. The bass also sounded pretty undefined and in general, missing. The amp fixed that right up. Now bass is well balanced and has incredible extension like I have never heard before! These also respond well to EQ.
 
Second, these are well constructed, well balanced, isolating monitor cans: nothing more, nothing less. Do not expect some kind of great musical performance from these headphones. They sound good to me, but I have noticed some problems. Among the most prominent issues is the claustrophobic soundstage. The instrument separation is good, however. Traveling with these headphones worked for me, both on a plane, and in a car. After about 2 hours I have to take these off due to the clamping force.
 
All in all, these are well thought out monitor headphones. They allowed me to rediscover my music collection. If you have not heard good audio before being able to hear drums flex, and acoustic guitars resonate, the experience will be magical. If you plan on buying these get an amp. If you don't need isolation get the HD-558 or HD-598.

These are...ok. I expected great things from these, and if they were my first pair of real headphones, I guess I would like them, but compared to many others, including the similar Amperior, they're simply missing something. The bass is there, the treble goes nearly high enough, they're clear and the instruments separate, yet they just don't excite. They really are professional monitor headphones, and nothing more and nothing less.
 
I kept these things for their high isolation so I can watch movies at night, but really I should trade them for some Sony 7506, which is what I would recommend over these.
 
Objectively, as a studio headphone, these are a good product. Subjectively they are kind of meh, though.

I originally got these headphones because I was looking for headphones to use both for late night listening (in an apartment complex with thin walls) and travel.  So for me isolation was one of the first things I was looking for, and these headphones deliver that in spades.  Unfortunately, it comes at the cost of a fairly tight fit around the head.  Not enough to really be uncomfortable (I've used these headphones for hours on end), but enough to be noticeable.  The headphones are fairly bulky in size, but fold for travel, and I've found them to be much more durable than I was expecting given the reviews -- after several years and numerous airplane trips, the headphones have suffered no visible damage. 
 
I listen mostly to classical music, and I found the sound to be quite good -- everything comes through clear and clean, and I have no problems with any particular range in the spectrum.  Given my needs (high isolation with decent sound), these headphones were exactly what I was looking for. 

These were my first pair of cans and since no one else has yet to submit a review for them I thought I would go ahead and write one.

First Glance:
These were made primarily for studio use and the have a very classic look to them. Nothing fancy. They come with a coiled cable that terminates with a 3.5mm jack with threads for the supplied ¼in adapter.

Build Quality:
The headband is made of kind of plastic along with the rest of the headphones. They have a leather-like pad on the headband and around the ear cups. There have been reports of the plastic headband cracking but my pair has seen no such damage. Overall the build quality is acceptable for a pair of headphones in this price range.

Comfort:
They are not particularly uncomfortable headphones but after an hour or so of listening they might begin to become uncomfortable. They are quite light feeling on your head compared to my AKG 271MKII's and feel almost like a pair of Grado’s expect a little heavier. They don’t have a really strong clamp on your head so that is not uncomfortable either. Overall they are pretty comfortable but there are more comfortable cans out there.

Sound:
Now for the important part: How do they sound? I have probably put around 50 hours into these headphones and this review is based upon that experience in addition to the specific testing that I did. Here is my signal chain: Sony DVP-NC80V -> Gary’s PA2V2 -> Sennheiser HD 280 Pro. To me they seem to have an kind of neutral sound probably due the fact that they were meant to be used in the studio which makes me feel that are not great for enjoying music as they have an almost cold sound and at times the high frequencies can get fatiguing. The low end is present but it not very punchy, it is just neutral. Acoustic guitars and cymbals cut right through and stand out but at times are a too sharp and require you to turn down the volume. Since they are sort of cold they are also quite transparent and individual instruments usually stand out. The mids seemed to be recessed and vocals never really seem to jump out at you. Overall this causes a less than satisfactory listening experience because they never really bring the music to life. That doesn’t mean they aren’t good headphones. They are great in the studio for someone looking for budget mixing/mastering headphones because, like I said, they are transparent. They are great for monitoring due to their isolation which is quite good even when no music is playing.

Conclusion:
These headphones are a great backup in the studio or for giving to performing musicians or just for the home recordist on a tight budget. Although I would not recommend them to a fellow Head-Fier who wants to use them to listen to music collection. In the $99 price range there are better headphones for enjoying music, maybe something like the Grado 60i’s. I hope this review is helpful.

[size=small]Well to start off lets list the headphones I am comparing these to... [/size][size=small][/size]
[size=small]Over Ear [/size][size=small][/size]
[size=small]Dr. Dre Beats (Studio) [/size][size=small][/size]
[size=small]Sennheiser EH 150's [/size][size=small][/size]
[size=small]Sennheiser HD 202's[/size][size=small][/size]
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[size=small]On Ear[/size][size=small][/size]
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[size=small]Dr. Dre Beats (Solo)[/size][size=small][/size]
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[size=small]In Ear[/size][size=small][/size]
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[size=small]Altec Lansing Back-Beats Pro [/size][size=small][/size]
[size=small]Ink'd Skullcandys [/size][size=small][/size]
[size=small]Monster Turbine In Ear [/size][size=small][/size]
[size=small]Dr Dre Beats [/size][size=small][/size]
[size=small]Monster Turbine Pro Copper[/size][size=small][/size]
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[size=small]The design of these headphones is a clever design, the coiled cord was a huge advance from constantly rolling over my EH150 wire with my computer chair. Another weak point I find in just about every pair of headphones is the connections at the end of the cable. On these the end user is able to remove and put in a new cable which is a huge advantage in my opinion. The headphones themselves are a thick sturdy plastic with plenty of padding, they do get warm on your ears after a while but what do you expect.[/size][size=small][/size]
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[size=small]The Sound I was quite disappointed with at first when plugged into my Samsung Infuse smartphone. I thought they were worse than any other of the large headphones I listed above. That is when I said well they are STUDIO headphones (So were the STUDIO Dre's and they sounded fine on this mobile device) however when plugged into my computers or any studio device they blew me away. Bass is incredible, if you like BASS STOP LOOKING these are what you want, FAR better than the beats. They have a warm sound to them. While delivering great bass they also have great trebles. I listen to a mix of music from jazz to some rap to hip-hop etc. [/size][size=small][/size]
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[size=small]OVERALL I would absolutely recommend these to a friend, in fact I am getting them for a friend for Christmas. I would give these a lower rating for not working on mobile devices as well ie phone and ipods however they are specifically titled STUDIO DJ headphones which implies computer and on the computer they go far beyond their expectations. [/size][size=small][/size]
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[size=small]OH and the big question YES they are better than Studio Beats!!!!!![/size]

These have a very thin and dull sound. There is a noticeable lack of low mids / bass, which leave the headphones sounding very cold. There is no sound stage to speak of. I just can't find any redeeming qualities in the sound department. My cheap Senn IEMs sound much fuller than these.
They do isolate extremely well, at the expense of strong head clamping and ear warmth.
 
Stay away from these. Frankly I'm astonished that these have 4 stars (as of this review) on a site dedicated to headphones. I suspect people want to believe their $80 were well spent.

[size=10pt]Too many people first starting out in the $100 category for headphones choose the 280 as a starting point.  Without directly A/B comparing the 280 pro against other headphones at this price point is you are going to leave yourself room for much improvement.  The isolation is about all that is beneficial from this headphone.  The durability is unanimously horrid and sound quality is hugely dependant upon how to fit your head and seal around your ears.[/size]
 
[size=10pt]If you are looking at these for you first choice in "quality" headphones I would listen to the Audio Technica ATH-M50's before making your final decision.  If you like In-Ear type headphones try the Brainwavz M2.[/size]
 
[size=10pt]One interesting fact about these headphones is that the outermost part of the shell is too thin which appears to dampen the sound a bit.[/size]
[size=10pt]http://www.youtube.com/watch?v=uHkb4bhdnRA[/size]

I bought these a while back to commute with on the train, hoping to block out some of the noise. Not only do they do that, but they sound great. 

I have had these for about 5 years. It is not the most exciting sound when compared to the Grado 80's in similar price range for UK. But the sound is reasonably detailed and neutral enough for home recording use.
 
The closed back design and cushions do keep most of the sound in so spillage into mics is minimal. The same applies to nearby friends and relatives!