Sennheiser HD 25-1 II Professional Headphone

I never thought that there's such a headphone like this existing! Everything that I'm looking for for a headphone, I found it all on this hp. Cool looks (at least for me), changeable parts (especially the cables), superb clarity with excellent bass response, and lastly, known for its superb durability.  

I bought the Sennheiser HD 25-1 (adidas) after my ATH-M50 had a loose connection and i had to return them.

Though I loved the M50's, they made me realize that a headphone is not all about sound quality.
Their isolation just didn't do it for me, and the pleather pads got my ears sweaty all the time.

The HD 25-1 finally does everything I need it to do.
The isolation is top notch, and the velour pads are more comfy then pleather while not getting sweaty.

Sound:
The sound quality of the HD 25-1 II was horrible out of the box, but they got better after a few minutes.
I didnt notice much of a burn-in process after that, and was quite disappointed with their sound, cause the only thing they did better then the M50 were drums and bass, while lacking a lot in highs, detail and especially soundstage and imaging.

After two weeks of frequent use and over-night burn-in (~200 h) they suddenly made a BIG leap in sound quality and especially detail and extension.
Compared to the M50 they sound more refined and detailed while also revealing a lot of bad recordings/ sources. the impact on drums and bass is just heavenly, like the overall bass response.

The only thing they lack compared to the m50 is imaging(not existant) and soundstage.
But since I use them as portable headphones mainly, that doesn't bug me at all.

Conclusion:
the hd 25-1 is a really decent hp and definitely one of the best portable headphones.
I especially love the user customizable style, cause i don't have to worry what might happen if my warranty were to run out.

If you find the pads to be uncomfortable, wash them in warm water. It makes them smoother and allows a better fit and comfort for the head.

I have previously owned a lot of headphones, but I felt the need of an all-in-one solution that I could use at home or on-the-go. So I scoured and found that the Sennheiser HD25-1 II is the perfect headphone for my needs. It is a small, supra-aural pair of headphones with superb sound quality in its price range and category.
 
Construction:
The HD25-1 is a very rugged set of cans. Although lightweight and looks flimsy, it actually holds well against constant abuse and wear. The split-headband design allows for both a secure and comfortable fit, perfect for lengthy listening sessions. The earcups themselves are made of hardened plastic, and do not easily scratch or dent when hit by an impact force. Lastly, the provided stock steel cable has great tensile strength to maximize longevity. All of these parts are easily replaceable, so the headphone can last for years and years of usage.
 
It may not be the best when it comes to isolation, but it does its job well in blocking out external noise like the bustling city, airplane engines, and so on. Although the clamp is fairly tight, it's not as bad as the one from the AKG K518 DJ. The pleather and velour pads also add to the HD25's comfortable fit.
 
Sound:
As I write this review, I have already clocked in about 200 or so hours with this pair of cans. Overall impression, the HD25-1's sound quality is excellent for a closed headphone. Although there is some slight sibilance in the high treble frequencies and soundstage is a bit closed-in, it still sounds great straight out of a DAP or from a headphone amp.
 
It retains the classic Sennheiser laid-back house sound, but adds a generous bit of Grado's upfront, edgy kick to it. The result is a pleasing mix of smooth-yet-aggressive sound signature that's hard to come by in other headphones; it reproduces lush vocals, deep, controlled bass, and detailed highs for a can of this size and type. Suitable for almost all genres of music, the Sennheiser HD25-1 is a very flexible can that's sure to please a lot of people.
 
Conclusion:
Although a bit pricey at $199.99 in most stores available online, in my opinion the Sennheiser HD25-1 is a great buy in this price category. If you are looking for a portable headphone with sound quality rivaling full-sized cans, I strongly recommend getting the HD25-1's.
 
PS: I have included pictures of my HD25-1 II as seen in the product photos, to better judge its design and construction.

Being a non-professional, but a general music lover, My review will probably be in layman's terms, but why not. It will give the perspective from someone that observe music in a different way than the purely analytic fashion.
 
Once, I had a great home stereo consisting of NAD CD-player, amplifier and B&W speakers with some fancy cabling. -So I am not completely rookie regarding what sounds good and not. Neither am I a person that thinks that resonating boomboxes (cars) driving by is coolz because of lotz of basz. I like to hear all kinds of music. Anything from Mozart'ish music to music 'designed for serious PA-systems'.
 
Being without my stereo for the longest time and getting tired of the 'noise' rendered by my speakers integrated in the laptop, I figured out it was beyond due time to get myself some headphones. Getting a proper soundsystem is out of the question due to limited space and girlfriend.
 
First problem was: What am I looking for. Go for a pair that is more fitting for the stuff you listen to the most. If You only listen to classical orchestras and alike, I guess You should stop reading. You need to look for stax-phones. Very Expensive. Only worth having if you are a feinschmecker.
My playlist when trying out music is stuff like Deep Purple, Child in Time, Roger Waters Amused to Death, preferably the whole album. Nina Simone, Feeling good, Peggy Lee, Fever, Jazz, Blues. That kind.
That'll tell me wether there is bass at all, if there is decent mid-range, and also if the treble is non-offensive.
 
By reading a lot of reviews, these phones came out pretty good. Although! -The impression I was given by other reviews were that they were a little expensive compared to the sound given. This was when my critically inclined mental alarmbells went off. Things like being warm, 'muffled', having a 'veil' between the music and ear, making the music feel distant. I then recalled the good old days, where I built my own speakers, -the horror of screwing up the expensive hobby project, just to later have that Aha!- feeling of having to actually 'run in' the speakers before they are able to show off what they are good for.
 
Eventually, I decided for  these ones. I know Sennheiser from before, and I have never had/heard about any real issues about them before, Not being tempted by any fancy modern bling with buttons, sliders and glossy paper/plastic, I found a dusty box pushed in the back of the shelf.
 
The reviews were per se correct. warm, muffled, not very precise music. -So I bought them.
Day one. One big ''Meh. I exchanged the fake skin pads with the velour ones. Much more comfy.
and playing music, wearing them for six hours, before my ears got physically tired. I have a small head by the way. If you have a full size head, perhaps consider something else. They are a little tight, but I am trying to expand the headband(s) a little by the use of something wider than my head. This is probably the only minor con i have with the HD 25-1 II.
Day two. Sleeping well, doing other stuff, going back to my headphones, turn on the music. Same repertoire as yesterday. - There is a difference already. there is actually a soundstage there now, albeit small. they veil is disappearing and it doesn't sound that warm and muffled anymore. It is not neutral sound, but on the other hand, if I were to listen to a lot of classical, I wouldn't buy 'rock-speakers' anyways. I read reviews about how the phones were lacking in the upper levels, that sounds like -'S', -'SH', -'CH' etc would be... ...not perfect. Well, day two improved from day one in this aspect too.
The bass wasn't 'fluffy' anymore, but still deep. actually plenty deep, imo. and the midrange had improved a lot. from having to 'look' for it, to get it all the way to your ear without having to notice it was missing. Six hours, before they get uncomfy. -and after six hours, anyone will get tired in their heads/ears.
The headbands are not noticeable... ...and the cable is not in the way, nor noticeable.
Day three. Hah. Even better. After a total of 18 hours, the phones are now ready to be listened to.
You could say the virginity of it is now gone, and it is ready for some proper exercise and training.
I am not going to blast the volume on max for any reason, just so its said, but now i don't mind my equally critical friends to listen to them.
Day four. time to write a review.
I can only assume the sound in them will get better and better as time goes by.
The only, and ONLY thing that would make these better, were if the sound picture was wider and deeper.
It isn't a must, but it would be nice. After listening to High-end systems with SNELL speakers, more expensive than my pants can carry the cash, an open environment, -or the lack of it iin this case -will be burnt into your mind, and one will never be completely satisfied, unless buying super expensive stax with equally expensive amplifier(s), used on an equally expensive high end stereo setup.
 
These are lightweight, durable, good bass, good mid-range, good treble, even for sibilant music (Beware of Justin Bieber... ...the phones can't take that. The speakers will crack and fall into a hot,deep pit where beelzebub and his minions are removing impurities from the liquids in their forges.)
Seriously, the higher areas of music are just fine in these phones. -already by day three/four.
Every part can be exchanged.
If only the Amperior was cheaper, I'd go for that one. It is better, but kinda expensive if one doesn't have the money for it, you know what i say.
 
All in all. You can't go wrong with these ones. -unless you have extrordinaire music taste, are analythical instead of enjoying the music, like a nice glass of brewerage. I don't taste and spit the red wine. I drink it, and enjoy it for what its worth..

I'm pretty far from what I'd consider to be an audiophile.  I know that based on the extremes that people can go with this stuff that I'm never going to bring myself to justifying that kind of obsessive behavior, but I do believe in quality and performance and when you find something that works that the price is usually well worth it.  These headphones are the definition of money well spent.  I had bought blister pack junk in the $50-100 range for years with about every single year requiring replacement.  Not only did they not hold up, but they just never really sounded great.  I think that the sound quality has been discussed to death on these over the years as they are far from being a new product.  The only thing that I'll mention in that regard is that they are one of the most sensitive sets of headphones I've ever heard. When I was shopping for a "big boy" pair of cans I A/B'd every single headphone I could get my hands on and I discovered pretty early on that some of the higher end ones were going to require a dedicated headphone amp.  These do not.  I would be afraid to put an amp through these out of fear of blowing my ears out.  Portable, computers, etc., all drive these to insane volume levels with no problems and to me that means that their amps don't have to work as hard so I have less chance of distortion from overdriving the circuit. 
 
Perhaps I'm mistaken, but it makes sense to me.
 
The reason why I'm posting this "review" is because I recently replaced the cord on mine.  Now it wasn't that it wasn't working any longer, but I wanted a coily one so that I wouldn't be running over it with my chair anymore and I came across this place in my online search for a replacement.  It's funny because this was the place that I found when I was shopping for them the first time.  I thought that it would be cool to do a ten year trial period review. 
 
I've had to replace the earpads once.  I've replaced the cord with a coily copper one from Sennheiser.  Now I don't get all wrapped up in the oxygen free depleted uranium titanium shielded kevlar cable stuff, but I did notice a marked difference in sound quality.  Not massive, but noticeable.  While I'm sure some will argue that is because of the copper I honestly chalk it up to the fact that the other cable had been run over about 2 million times in the last decade by a chair containing my large backside.  I'd like to see how well you performed after that kind of abuse.  The fact that it still worked in the first place is amazing to be honest.
 
I'm not an occasional headphone user either.  I'd say that over the course of a month there is probably about 3 days in there that I don't use them.  I have never had a second's worth of problems with them in that time. 
 
Some people may not like the way they sound.  I love them, but everyone's taste is different.  But I don't think that I've ever owned anything as reliable and if you calculate the money that I spent on headphones prior to buying these I would have saved a few bucks if I had just bought these in the first place.  If you figure out the cost of replacing $50 clunkers over a ten year period it's not even worth considering.  I've not only enjoyed outstanding performance the last decade, but I've actually come out about $250 ahead in savings on garbage.  Subtract about $100 for replacement parts (pads and cable) and I still have $150 leftover and a pair of headphones that are still working as well as they did when I bought them ten years ago.  I don't think that I even have anything in my house that's ten years old anymore (besides my kid and his days are numbered). 
 
One of the best investments in anything I've ever made and I can't recommend them highly enough.

Haven't had these for very long but impressed upon initial listening!

The problem with having a reference-grade pair of headphones for home listening (in my case, Grado's amazing Prestige Series SR325is) is that when you start looking for 'phones to listen to away from home, just about everything you try inevitably comes up short in one way or another, and the name of the game becomes "which set of compromises am I willing to live with?"

For me, the current crop of headphones aimed toward portable listening is, at best, merely acceptable. I could drag out the usual suspects to use as punching bags, but we already know who they are; just think style-over-substance and there's no need to name names. But there are a few seriously-mediocre 'phones out there offered by outfits that should definitely know better (AKG, I'm looking at you). Really, nothing I listened to in the "portable headphones" category did the trick, which is rather astounding given the money being asked for some of the upper-end models.

Then, while grousing about this situation to a sales guy at the headphone counter at J & R the other night, I got a suggestion I should have thought of before: ignore the "portable" category altogether, and audition something a pro would use. However, one good reason why I hadn't thought of this is that most "serious" headphones also typically sport some serious size and weight, and aren't always something that's easy for something like an iPod to drive at satisfying (not ear-splitting) sound levels. Yes, wearing big 'phones on the street is apparently cool again, but I prefer being a bit more discreet in my headwear, although I'm about done with in-ear phones and their assorted anomalies.

The sales guy then handed me a pair of these Sennheisers. I listened. I looked them over. I listened again. I was sold, simple as that.

They're decidedly ordinary-looking, literally dull. Sennheiser didn't exactly go out of their way to make an unstylish headphone: this is a model that was pitched initially to people who care a lot more about a 'phone's performance and reliability/durability than about how cool they look (or think they look) while wearing them: recording engineers and producers, sound-reinforcement people for the stage and the screen, sportscasters, and, of course, DJs. Think of the '55 Chevy James Taylor and Dennis Wilson drove in Two-Lane Blacktop: not slick, not working too hard to be cool, but clearly having what it takes to do the job.

And, what a job! Riding the train or bus, or walking the streets, I get the music, full, deep and wide...or not, depending on the recording. Being more of a true "monitor" headphone, the HD 25 doesn't do much in the way of juicing or monkeying around with the signal in the name of making a grand impression; if the recording is good, you'll hear just how good it is, perhaps for the very first time while away from your "reference" home 'fi. If the recording is sub-par, you'll know that, too, but the result won't necessarily be unlistenable, just minus any sugarcoating.

A few have pointed out the HD 25's nearly all-plastic construction, regarding it as "cheap." There's nothing cheap about this headphone's materials or construction: having been on the market for well over a decade, its design and build quality have been proven countless times in the professional field, where people are not known for treating gear with kid gloves. In the hands of the average consumer, these cans will easily outlast any flavor-of-the-month style-phones by an order of magnitude.

As durable as these are, they're also a damn sight lighter than your typical please-don't-drop-me bling-phones. I won't say it feels like you're wearing nothing on your head, just that it's a light touch overall. For some people, however, the pressure of the headband's "clamping" effect might be a bit much for listening much beyond an hour; this gradually eases as the headphones are broken in.

And, speaking of "broken": if by some freak event you manage to do damage to any part of the HD 25, that broken part can be replaced; Sennheiser keeps an inventory of spares if needed.

(As an aside, these headphones happen to be manufactured in Ireland. Take away what you will about that.)

That's the picture for you. I love the things. I think there's a fair chance that you'll at least like them.
 

Old timer which is still the best.
I love its dynamic sound but can brings fatigue after some hours.
Every things is there :bass, mids & highs with good details.
Every parts can be changed to make sure it will last long,
The only complaints I have : it doesn't fold 
 
I think it is still the best on-the-go headphones
 

I bought these puppies just before Christmas and they have been a revelation.
 
I can't tell you how much they suit my listening tastes. I love close listening with lots of treble and tight bass and these deliver this in abundance.
 
Never before have I been this sad to take a pair of headphones off.
 
I used these for traveling to work but have been using them more and more inside as my main headphone. I can appreciate that the sound may not be for everyone (no sound is) but if it is then, sweet baby Buddha are you in for a treat.
 
The build quality is exceptional and the anti urban styling spot on. I even (unlike most) like the pleather comfort!
 
I can't see me replacing them anytime soon.

Seriously, these things are built to last. When the apocalypse occurs in 2012, this Sennheiser would be left intact (maybe the wires would get destroyed). And for future generations of the human race (or whoever takes over the earth), they would be a relic of the old world.

I own two pairs, one for work and one for portable use, I treat the portable headphone with utmost care, like a baby, while the one for work gets tossed around and daily abuse, and yet both look the same. On a note of the clamping force, the frame needs to burn in, so that the force loosens and optimum comfort is achieved.

Sound. How does it sound? It's a bit colored, I think. Definitely not neutral, but I've gotten over the "neutral stage" where I cared about neutral headphones, I just want to enjoy my music with clarity. The bass mids and highs are fairly even in terms of balance, but not perfectly balanced. What's very noticeable is that it has punchy bass like a Grado, not deep rumbling bass. And absolutely no soundstage, which creates intimacy, or in my case, that in-your-face-sound that you get from Grado. I use these for speed metal, thrash metal, power metal, traditional metal, etc. Metal that's fast and guitar driven. They're like a closed back Grado, but not as bright.

I got it for free from work, as this is what they use for their stuff such as recording, calibration, etc. They previously used V6's, 440's and T50RP's, but they settled for the HD 25-1 II. There is a huge increase in price to the consumer, but I'd imagine when a company purchase these, the difference is not all that great. They are the basic edition, but I wish I owned a pair of the Adidas versions.

The HD 25 series has been around for 15 years and this has been my 2nd purchase of the famed dual-band headphone.
 

 
Value: 10 years ago, if you are purchasing a $200 headphone it would've sounded absurd. Thanks to Beats by Dre, $200 headphones are now a steal. For $200, you get 2 pairs of ear pads (1) velour and (1) synthetic, also you get a nylon carrying bag, and of course the star of the show, the HD 25-1 II.
 
Audio Quality: HD25s are a favorite among DJs and broadcasters, although it is primarily designed for studio use, I rarely see this headphone used for mixing and remastering. The most common headphone, I see in studios are the ATH-M50 and SRH-840s.
 
Bass: It is there, present and just about right for a variety of tracks such as rock, hiphop, jazz, RnB, acoustic. But, if you are a basshead, this might not be for you. Bass is not deep as the ATH-M50s and the pacing is not as fast. This headphone will suffer from house music and dubstep. 
 
Mids: Now this is HD25s cream, the mids are very revealing, it is an ENG headphone after all, it will be unforgiving on bad recorded tracks as you will hear all the pops on the vocals. This is great if you like absolute precision when mixing. And, those who love vocals will definitely enjoy this.
 
Highs: Average, rolled-off in some tunes, very common in studio headphones. Purposely done, not to fatigue your ears for long listening session.
 
Design and Comfort: HD25s are a ruggedly designed headphones, they are used almost everywhere by professionals. It is a favorite among DJs because of its isolation. This headphone can cancel out 20db of noise, better than those noise-cancelling headphones with batteries. Standing right into a noisy washing machine, I can't hear a thing with only 60% volume from an iPod, that's amazing. With isolation, you lose comfort. But in my case, I find this headphone very comfortable, the padding are well-balanced to distribute the clamping force of the band.
 

 
If you have a small ear, then it be uncomfortable. For medium and large ears, they'll be comfy since they will sit just on the inner side of the ear. Build quality is very good, plastics are tough, but not as polished as say Audio-Technicas. The plastics on the HD-25s are unpolished and raw. But, since I own this for 10 years, they are very reliable.
 
Split band will secure the headphone better, although, I'm not a fan of it. I use them as a single band. Also, there are a lot of aftermarket parts for this headphone, no worrying in breaking them. Replaceable ear cups, headband, cables with different flavors, ear pads and more.

 
Overall: The past 10 years, nothing has changed. But, this little headphone will continue to wow new enthusiasts and it will continue on production forever. If there is something to improve, it is to polish the plastic make it look more presentable and classy. Overall, it is still a highly recommended headphone, and it is my favorite DJ headphone for the clubs and commute.
 
 
 
 

The above says it all, as well as numerous other reviews. I luv these supra aural cans,...and I'll keep them till I either go deaf or die!

I love these headphones. I just recently got these headphones for Christmas and they are AMAZING. In the past few years I have created a huge love for music and found this site when looking for some really good quality headphones. I love the sound quality of vinyl music and these headphones are great because they work with my record player which uses a 6.3mm headphone input. Hands down the sound quality of these headphones are the best. They don't have too much bass and have a nice clear precise sound. My only complaint is that at first the headphones are really tight. I am an average weight 21 year old girl and even I thought these headphones were tight at first. I do have to mention that I do have a huge scar on my head because I had brain surgery when I was 16, but even considering that I thought they were tight fitting. Despite the tight fitting design, you can't beat the quality of these headphones. Buy these if you want a truly good sound quality from your headphones.

The HD25s are a legend, really, so I'll just say I love the sound. They push all my aural buttons, with a fast, agressive sound (not quite Grado-like as some would say), punchy bass and great detail. I feel these things just "throw" the music at you, making you listen. Don't know how some people could call them boring, really. They have a solid bass, a dip in the midrange which gives them a certain natural feeling, free of colorations, and somewhat sharp treble. Nothing is overdone, nothing is missing. Soundstage and neutrality might be questionable to some, the design certainly is, but these cans are something you really have to try, especially for rock, metal or rap.

 
 
 

No introduction is needed for this pair. The "rumours" about the sound quality are true. Some people disagree that they are good for music production, but I am not using them for this reason, so I cannot comment on that. When I am listening to music I prefer it to come to my ears as the musicians and sound engineers intended to, and I think that these headphones are doing it to a great extent.
 
Some people also find them to be uncomfortable. Well, they are not as comfortable as HD 598 for example, but this is to be expected from a closed-back pair. I would not expect more comfort than what they give. I'd describe my head as medium size, so people with large heads may find them a bit more uncomfortable.
 
Overall, very, very highly recommended!

The HD25-1 has been my favorite (trans)portable headphone for quite a few months. I spend a few nights a week away from my home rig and the HD25 works wonders with my iBasso D10 and netbook. Hi-fi on the go has never been so rugged and simple. Best of all is their sonic versatility – though my backup portables, the AKG K181Dj, excel with certain genres and recordings, the Sennheisers perform more than adequately with anything I can throw at them.



Build Quality: When it comes to build quality, Sennheiser’s flagship portables can do no wrong. The structure of the HD25 is painfully elementary. They are neither flat-folding nor collapsible, with very simple rotating joints and removable metal hardware. The rough black plastic is resistant to cracks and scratches. A thick and sturdy steel cable, terminated in a beefy L-plug, completes the picture. The headphones are also very light and not likely to get damaged from falls. Lastly, every single part of the headphones is user-replaceable. From the detachable cabling to the headband padding to the cups and joints, the HD25 can be disassembled completely in just a few minutes.

Comfort: The HD25 is surprisingly light compared to headphones such as the AKG K181 and M-Audio Q40. The adjustable dual headband exerts very little pressure – the majority of the force is applied by the supraaural coupling. Though clamping force is fairly strong in the HD25, the structure does a great job of distributing it over the entire surface of the pads. The cups have a good range of motion despite lacking any joints whatsoever and conform very well to the shape of one’s head. Vinyl pads come installed on stock HD25s but some versions include the optional velour pads as well. Even if that isn’t the case, at $7+shipping the velour pads are a worthy investment, providing a comfort improvement at the expense of a tiny bit of isolation. Overall comfort falls just behind the likes of the impossibly light Senn PX100s and the circumaural CAL!.

Isolation: Though in general portable headphones can never isolate as well as IEMs, the HD25 can compete with certain shallow-insertion in-ears. While the vinyl pads isolate just a bit more than the velour ones, the tradeoff is unlikely to be worth it for most users. Even with the velour pads the isolation crown of the HD25-1 can be usurped only the hard-clamping AKGs and only if you’re lucky enough to get the AKGs to seal properly.

Sound: Upon first hearing the HD25-1 I was absolutely convinced that I would be giving them a perfect score in sound quality. Having owned them for a while, however, I can’t help but notice that for $200 headphones they are just slightly lacking here and there. But the fact that I am still using them as my primary portables is certainly telling of the fact that they are a competitive product. They are well-balanced, have good clarity and detail, and are quite transparent when it comes to sources. The bass is tight and accurate. It’s hard-hitting in character and more punchy than powerful as opposed to something like the K181Dj or M-Audio Q40. It has impressive extension, though it won’t keep up with the M-Audios down to the lowest reaches. It is also well-textured and does not bleed into the midrange. For a portable headphone the quantity of bass is just right – a bit more than what one would expect from an analytical headphone but far from AKG K81/K181 quantity.

The mids are neutral, clear, and detailed. Articulation is very good and sounds are well-separated. However, the HD25 is lacking noticeably in both soundstage width and depth, at least when compared to most full-size headphones. Most of the other closed portables I own don’t exactly shine in soundstaging either but I can’t help but be disappointed that the smaller and cheaper PX200-II has a more spacious sound. Sheer size aside, soundstage positioning is fairly precise and instrumental separation is excellent on all but the densest tracks. Towards the upper midrange the HD25-1 struggles to stay smooth and as a result is very unforgiving of sibilant tracks. The high end is quite present and reasonably extended but comes off a bit edgy and clinical at times. The overall sound, though, is quite pleasant and works particularly well for genres not dependent on soundstage size for the full experience. All of my quibbles aside, the HD25 is as good for use on the go as any portable headphone I have heard.

Value. (MSRP: $299.95; Street Price: $199) By far the most expensive headphone of the bunch, both in street price and MSRP, the HD25-1 is on another level in terms of balance and detail compared to all of the other featured portables. Compared, however, to full-size cans in the price range, as it sometimes is, the HD25 can come off as dull and rather compressed-sounding because of the narrow stage. The hard treble can also be a bit fatiguing for home use. But of course such comparisons are unfair precisely because I am not comfortable wearing my full-size cans outside while using the HD25 comes naturally. It is this versatility that makes the Sennheisers well-worth the $200 price tag and one of the easiest portable headphones to recommend.

Manufacturer Specs:
Frequency Response:16-22,000 Hz
Impedance:70 Ω
Sensitivity:120 dB SPL/1mW
Cord:5ft (1.5m), single-sided; Angled Plug
Space-Saving Mechanism:N/A
 
 
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To see how the HD25s compare to the other portables in my collection please see here.

I have own the Sennheiser HD 25-1 II for more than 6 years now, and everything is still in perfect condition. I have always love the analytical sound this unit delivers... These have turn to be my personal favorite headphones for tracking live instruments and recording vocals, but I use them to listen to music when traveling, and they are my favorite portable headphones as well.
 
They are not really that confortable, I find them to be a little uneasy to wear for long periods of time, but they isolate really well and sound great with theire slightly v shaped sound signature. I will recomend this headphones for anyone looking to something portable and with great sound isolation.

 
The HD 25-1 is more than a great sounding headphone, it has stood the test of time, and proved to be one of the worlds most durable and versatile headphones. There's many detailed reviews of this classic headphone, so I won't go too much into the details. In short, all I can say is the hype and praise these headphones have received is well deserved. After owning these, I began noticing professional DJ's and Sports Announcers on TV wearing these all the time. Funny I never noticed that before, but I can see now that they use them for a good reason. I think the reason these are so well regarded is more so because of their design/comfort/durability/versatility vs their sound quality (which is great too).
 
Sound (9/10)
 
The sound signature of these is quite balanced, with a slightly above average bass response, likely due to the above average isolation they provide. The sound stage is about average for a closed headphone in this price range, but the separation on more complex compositions is impressive to me. They are very sensitive and easy to drive, which makes them ideal for portable use. They get loud enough to be dangerous, even from portables. Like most higher end headphones, they also benefit from high end amplification, but it's by no means required to reach their potential. Due to their balanced sound signature, these will please lovers of any genre of music. They are equally suited for gaming or movies also. Gave it 9/10 due to the average sound stage, there's other closed headphones that do better in this regard.
 
Design/Comfort (10/10)
 
The reason Sennheiser built a reputation off this model is the design and versatility of it, it is a true feat of engineering. The plastic is of high quality, making them light and durable. The clasping force is moderate, and combined with the Velour ear pads, I notice no discomfort at all when wearing them all day, even with my glasses on. With the leatherette ear pads they come with, you will get warm after 1-2hrs, but you get a slightly better seal, which improves bass impact slightly. I think the added comfort of Velour more than makes up for the unnoticeable decrease in bass impact. It's easy to get the right seal on all head sizes/shapes. Once there on, they stay there, even when running/exercising. The split headband helps keep them from moving. 
 
They look good when there on, not overly stylish or big, a more minimalistic look. The cable is just the right length too (1.5m), and conveniently terminated to a 90 degree 3.5mm connector, with a screw on ¼ inch adapter too. For those who care, mine say Made In Ireland. Because these are so modular, you can easily take these apart and customize them with custom paint jobs or after market cables if that's your thing. All the parts are easily replaceable, and easily available, which is something no other headphone achieves in this price range with this sound quality and comfort/durability. For many, this headphone is the last one they ever purchase, simply because it won't break, sounds great, and is so versatile. For those who manage to break something, a replacement is easy to find. That's why you see so many professionals using these on a daily basis.
 
Verdict (9/10)
 
I highly recommend this headphone, for anyone. It will be the last headphone you buy. I can honestly say I was skeptical of the hype these had, but after owning them, I quit using all my other closed headphones in favor of this one, not just for the sound quality, but the versatility it provides. It's like a good ol' Acura; it might not look the most flashy, or perform spectacularly well in any one area, but it does everything well, takes a beating, and never lets you down. Gave it 9/10 due to the constantly raising price of this model.

I have had these headphones for a couple of days, and used/tested them intensely during that period.
I have a pair of mackie mr8 mk2 studio monitors, so this is the sound I am used to.
The sennheiser HD25-1 II are extremely populair, and this is one of the reasons i bought them, yet I was not satisfied at all.
First of all, the sound stage is extremely small, it actually sounds more like everything I was playing was in mono instead of stereo.
Also the headphone lacks in treble, and really does not have a lot of detail, this headphone is everything but balanced, so to call this a studio headphone is just wrong.
 
Don't get me wrong, it sounds good, has a lot of tight bass, really upfront (could be your taste) and goes really loud. And maybe if you are a pro and need a headphone that is built to last, and has an extremely high spl this is the headphone for you.
Otherwise, I think the headphone is a bit expensive.
 
Alternative: I have the beyerdynamic DT770 pro, these are closed, don't go as loud (as if you would ever need 120db in your ears), still more than loud enough though and have a huge sound space. Also I got them for 130 euro's, so that's 10 euro's cheaper than the sennheiser 25-1-II.
The only downside to these headphones is that they are quite a bit bigger than the sennheiser's 25-1-II.
Some people act like this is the best headphone in the whole world. With this review I am trying to tell that the 25-1-II really is not the best headphone, and that there are a a lot of alternatives.
 
EDIT
I actually have bought these headphones again, and love them!
My main headphone is the HD650, and I use the HD25-1 II for bass heavy music, portable uses and playing the drums. I actually don't mind the small soundstage for some reason, and love the sound.
I bought the velour pads for extra comfort, and the fiio e6 for portable uses.
 
Not sure if my first pair was falty or that my sound signature preferences has changed.