Sennheiser HD 600

Average User Rating:
4.8/5,
  1. BigBadBirdman
    5.0/5,
    "Reference Headphone for Opera and Chamber Music"
    Pros - Detailed, neutral, sound quality. Does not change the tone of the music.
    Cons - Needs a good amp to sound it's best.
    Introduction

    The Sennheiser HD600 is generally considered the reference headphone for Classical music and opera. I have owned mine for 17 years. I have purchased 5 other headphones since then but I still use my HD600 on a weekly basis and it is still one of my favorites.

    The Sennheiser HD600 is considered a neutral headphone. It will sound like whatever your recordings sound like; for better or for worse. The reason that I have 5 other headphones is that not all recordings sound perfect and many recordings benefit from bass and treble boost. But on the occasion that I have a recording that sounds great the way it is, the HD600 is the headphone I choose.

    My Setup

    I use CD, Blu-ray, and DVD as my sound source. I mostly use a Marantz CD6005 but sometimes use an Onkyo C-7030 as my CD player. I use a bottom of the line Sony for video.

    I drive all my headphones with a Schiit Asgard 2 headphone amplifier. Some of my other headphones sound fine being driven from the headphone output of CD player but the HD600 sounds significantly better with the Asgard 2 amp.

    The HD600 is designed for home use. I do not use any portable listening devices and do all my listening exclusively at home.

    I primarily listen to opera and orchestral music. I sometimes listen to jazz. If I watch a movie, the HD600 is my first choice of headphone. Movies are heavily equalized already and do not sound good with the added bass and treble boost of my other headphones.

    The other headphones I currently own are the Sennheiser HD700, Beyerdynamic DT-880, Beyerdynamic DT-990, Beyerdynamic T51i, and Philips Fidelio X2.

    My speakers are the Apogee Centaurs driven by an old Carver solid state amp and a passive preamp. I live in a small condo, so I cannot play my music very loud without disturbing the neighbors. I do most of my music listening with headphones and use the speakers for movies and television.

    Sound Quality

    The HD600 is known for its transparent sound quality. The sound is clear and detailed with sparkling highs and deep and detailed bass. Some will say that the highs are veiled and the bass is lacking but I cannot attribute that to the headphone as much as to individual recordings.

    Out of the 6 headphones I currently own, only the HD600 and Beyerdynamic DT-880 are ones that I would consider neutral. All the others boost the bass and treble. It is important to have a neutral headphone because recordings are normally already equalized by the sound engineer and when you use a headphone that acts as an equalizer, it can mess up the sound. To further complicate matters, if the engineer is using a loudspeaker that does not have a flat frequency response to mix the recording, the sound balance can be drastically altered.

    The Highs

    The treble extension is a point of controversy among headphone aficionados. Many claim that the HD600 and other Sennheiser models have a veiled treble. I mostly use the HD600 for opera and most of my opera recordings do not sound veiled at all.

    On the other hand, opera recordings that sound harsh on some of my other headphones can sound good on the HD600. So some people might want to call that veiled. I tend to think of the highs as “forgiving.”

    I think the reason some people think the highs are veiled is that they are comparing the HD600 to some other popular headphones that have boosted high frequencies.

    Regardless, the highs are fully extended and clear and most opera recordings.

    The Midrange

    The HD600 has a gorgeous, detailed midrange that I consider to be reference quality. The midrange is what made the HD600 famous.

    The Bass

    The bass is another point of controversy. Some think the HD600 does not have enough bass. I think they might be comparing the bass of the HD600 to headphones with boosted bass.

    The HD600 does not have a boosted bass but the bass is well extended and has detail. It all depends on the recording. Recordings with good bass extension will sound warm and deep. Recordings without much bass will sound thin.

    Since most of my other headphones add bass, I use my HD600 for recordings that already have a bass boost applied. For example, the remastered recordings of the Schumann symphonies conducted by George Szell have way too much bass added in the remastering. The original budget recording was just right. I cannot listen to the remastered recording on any other headphone than the HD600.

    Soundstage

    The soundstage on the recordings is accurately represented by the HD600 but like all headphones, the soundstage will collapse if you play them too loud. You have to get the volume just right for the soundstage to come into focus.

    One of the best examples is the recording of Handel’s Alcina conducted by William Christie. If you get the volume just right, it is like sitting in the first row, right behind the orchestra pit; with the orchestra below you and the voices coming from the stage.

    Conclusion

    The Sennheiser HD600 has been around for 20 years now. I have had mine for 17 and I love it more now than ever due to my recent purchase of the Asgard 2 headphone amp. It is my reference when I compare other headphones for addition to my collection.

    When reading headphone reviews, the writer usually treats the review as if the listener is only going to use one set of headphones for every recording. That might be true for someone listening to digital files going through an equalizer program. But I am listening to CD’s, DVD’s, and Blu-ray without any equalizer, so I end up using my headphones as an equalizer.

    The Sennheiser HD600 is the one headphone I use when I don’t want to change the tonal quality of the music. It is my reference for a neutral headphone.

    I usually turn to the HD600 for opera, chamber, and solo piano. For large orchestral music, I like the added bass and treble of my other headphones.

    The HD600 is excellent for movies since they are already equalized with added bass and treble.

    The HD600 is very comfortable and I can wear it for a long period of time, even while wearing glasses.

    If you are a fan of opera and chamber music, I highly recommend trying out the Sennheiser HD600. Many other headphones have come and gone but the HD600 is my reference headphones that all others are compared to.
    trellus likes this.
  2. garbulky
    5.0/5,
    "Amazing with the Emotiva Basx A-100 amp"
    Pros - Huge amounts of transparency
    Cons - Really needs a very beefy amp to open it up. The A-100 was the first that could throw it around.
    Having owned this headphone for close to a decade, I feel that I definitely have the experience to write about it.
    The first thing is..........if you don't have a headphone amp that likely costs as much or up to five times as much as this unit, you are wasting your money. This thing NEEDS a very powerful headphone amp if you want it to sound great. Otherwise it will merely sound good and pleasant. But you will miss the high resolution bass, the open treble. Pretty much everything that's amazing about them.

    Luckily I found the Emotiva basx A-100 amp priced at about 200 and with its resistor jumper taken off, it was just the prescription for this headphones. And what a prescription that was! It threw it from - probably about right for the price to right in to the high end of performance imo.

    So here's my review for it. If you are looking for an amp that can push unlimited dynamics with this thing look no further. Just remember to take the jumper off.

    My review:
    Y'all I bought this headphone amp and I couldn't believe it's selling for this price. It is a DREAM with the HD600s. The HD600's no longer feel dark or laid back. It simply came alive. Soundstage, resolution, unlimited dynamics. Oh and really low bass. Just insane really. Imo to beat this amp you are going to have to swing up to a Schiit Ragnarok. It has got huge amounts of power capability and I believe this is the reason the HD600's came alive. Lots of control.

    I removed the jumper and absolutely heard a difference in dynamics - there was no smear. Just lightning quick transients. The first time I felt my headphone rig was not second class to my speaker rig. The jumper limtis the current output of the A-100 to prevent high sensitivity headphones from frying. Not a problem for the HD600. With the jumpers off, the A-100 pushes a godly 1300 mwatts in to 300 ohms. Doesn't sound like much? Check out how well other amps do at 300 ohms? You'll be lucky if they squeek out even a 100 mwatts. I've seen amp units that gasp out 14 mwatts at 300 ohms.
    At lower impedances the A-100 will push 8.5 watts at 50 ohms more than enough to fry the headphones. Hence the jumpers to prevent over driving lower impedance headphones.
    But with the HD600's....it's just a dream.

    Speaker and DAC rig: (Axiom M80's fully balanced to Emotiva DC- to XPA-1 gen 2 monoblocks in class A mode + room treatments. With a source the Musiland Digital Times via BNC output. About a $4500 setup). I can't believe I'm saying this but it absolutely competed with this nice sounding speaker setup. In some aspects it did better as well.
    I dare you to find anything close anywhere near that's price range.
    Love it!
    [​IMG]
    Along with the huge torroidal transformer, you will see that it has a ridiculous 20,000 mf of capacitance and that performance really shows bringing very low bass and extreme control to this set of headphones. The treble also really opened up. I am definitely hearing more air. The control allows everything to sound holographic with large amounts of layering.
    [​IMG]
    trellus likes this.
  3. serman005
    5.0/5,
    "Neutrality Reigns Supreme"
    Pros - neutral signature, profound detail, lushness
    Cons - lean-ish sub bass, modest soundstage
    Introduction
     
    This is a review of the Sennheiser HD600 headphone. The HD600 has been one of the most respected headphones on the market for nearly twenty years. This review will cover construction, comfort, power requirements, sonic performance, comparisons with other headphones, and a conclusion about this world-renowned headphone. With that, let;'s begin.
     
    Technical Specifications
     
    Nominal Impedance 300 ohms
    Weight w/o cable  260 gm
    Jack plug  3.5/6.3 mm stereo
    Transducer type  open, dynamic
    Coupling  circumaural
    Cable length  3m
    Frequency rewponse  12-39000 hz
    Sound Pressure Leveel (SPL)  97 dB @ 1mw
    Total Harmonic Distortion (THD)  0.1%
     
     
     
    Accompanying gear for the review
     
    naim cd555, iphone 6S, MacBook Pro, ipod shuffle 2G, DK Designs VS1 Mk III, magni2/modi2, Bravo Ocean, Audio Note Custom 300B, HD598, HE400S, HD600, 
     
    Comfort and Construction.
     
    The HD600 is constructed primarily of plastic with a small area of carbon fiber on the band. The pads are velour as is the headband, which makes for substantial comfort. Clamp force is fairly snug, but I can wear this headphone for hours with little discomfort. I have an average sized head. There is plenty of room in the band for those with larger heads. Overall, I would say this is a well-constructed headphone--and it must be because there are people out there who have had theirs for a decade or more.
    One final note. My HD600 is brand new and it is not of the blueish hues that 600s of days past have been finished. Mine is black and the top of the band has a black and grayish paisley-like pattern where the word 'Sennheiser' appears. It is quite a beautiful headphone and is much better built than my HE400S is.
     
    Power Requirements
     
    I used a wide variety of power sources for this review. What I can tell you is that the HD600 requires a decent amp in order to shine. My ipod shuffle will drive them to loud levels, but it will not provide adequate power to support solid bass and optimal midrange. So, if you are looking at an HD600, be sure to budget for a good amp. You see the ones I use and they all drive the 600 to lovely heights--even the Ocean.
     
    Preliminary Impressions
     
    My first impression of the HD600 was of its detail On Pat Metheny's As it Is, the vocals were lush and rich, with individual vocal lines etched out from one another. The air around the voices was clearly audible.I smiled. I knew I was on to something. On Stravinsky's Rite of Spring, the woodwinds blaze a blistering path through the piece. I am in the room with them. They are real. The timpani are blasting acoustic energy at me, their echo clearly audible. On Larry Carlton's Last Nite, Carlton's guitar is harmonically layered like the steps of a stairwell. On Metheny's Minuano, something important emerges. It has to do with the treble. More on that in a bit. On Captain Fantastic and the Brown Dirt Cowboy, Davey Johnstone's guitar is lush and rich. I have never heard it sound so good. Wow!
    I keep spinning the music. And I sit back and listen. And settle in. It's going to be a long session.
     
    HD598 vs HD600
     
    The most profound difference between the 598 and the 600 is that the 598, which I like very much, has sluggish and muddy bass by comparison. It is very sluggish and cannot keep up with the music. This is true on the Pat Travers' Band's Heat in the Street, where the 600 is like a fine German car. The 598, tries its best, but it's an old out-of-repair Nova and it just can't keep up.. That said, the 598 soundstage is clearly better and wider than the 600's is. There is no doubt about it. Instruments occupy a much vaster space with the 598 than they do with the 600. Treble isn't as good with the 598. More on that later.The midrange on the 598 is very nice. But it can't compete with the 600. Vocals in particular are widely different on the two. The 598 is good. The 600 is superb.
     
    HE400S vs HD600
     
    The HE400S is a very good headphone. It has a gorgeous midrange and very nice treble. However, its bass is fairly rolled off starting at around 70-80 hz or so. Sub bass is kind of weak. This is especially notable on song's like Fourplay's Elixir, which has deep bass. The power of this line is lost with the HE400S. The HD600, on the other hand, plays that line with impact. It is not as powerful as my HD681 Evo, but it is still felt and heard. The treble is very interesting. On the aforementioned Elton John and Pat Metheny songs, the drummers use multiple different crash cymbals. On the HE400S, those cymbals all sound fairly similar. On the 600, on the other hand, those cymbals are all each totally unique and distinct sounding. It is remarkable the resolving power of the 600 compared even to the very good HE400S. With midrange, the 400S is thin sounding by comparison to the lush and rich 600. everything is just thinner. It still sounds good, but it is rendered less resolving and full by the HD600, which is just stunningly neutral.
     
    On Neutrality
     
    My definition of neutrality is a headphone that sounds good on  good recordings and like crap on crappy recordings. In short, it spits out what it is given without adding or subtracting anything appreciable This is what the HD600 does. It adds little and subtracts less from the music. In short, it is a remarkably neutral headphone that is a joy to listen to. Run out and buy two--you'll be glad you did.
     
    Conclusion
     
    The Sennheiser HD600 is a tour de force, lo these many years later. It has an absolutely spectacular midrange, exquisitely detailed treble, and a bass and sub bass that is more than adequate for me. They are musical. They sound like music. Not many headphones can say that. Though its soundstage is smaller than the 598 and HE400S, the 600 images quite well. Instrument separation is superb. It conveys the emotion of the music beautifully. As I alluded to above, run, don't walk, and pick one of these up. You'll find yourself listening for a long, long time.
  4. Nec3
    5.0/5,
    "Not a Veilheiser"
    Pros - Natural and Smooth Sounding, Modular Parts, Lightweight, Scales with Equipment
    Cons - Too many people hyping the "veil"
    So I finally have my hands on a headphone I never thought I would lay hands on. The Sennheiser HD600. Despite the high amount of positive reviews these get, I disregarded THEM in the past and explored other choices on the market. Even the Veilheiser HD598 that I bought were a slight disappointment. Mids sound too laid back and hidden behind a silk curtain, Japanese female vocals are slightly sibilant friendly from the sparkly treble, the soundstage isn't intimate enough and the bass seeped into the mids without much sub bass extension. But I like the mid bass presence, it is wide and gives any instrument; especially cellos, a meaty and down to earth presentation which was quite opposite of the Q701. Was it not for the Q701, I'd give the HD598 more praise. I know the HD598's are in a different price bracket now (150CAD) but at the time they were a bit more (200CAD) and costed the same as a Q701.
     
    The Q701’s. Their Mids are sweet, clear, crisp and definitely haunted by the 2khz peak that introduced artificial tones. The peak is a double edged sword that could also give some fortissimo-like emotion to poprock music, boost metallic textures from string instruments and it's the reason for the sweetness in the mids. The treble has texture and it's easy to tell whether the drummer is using a brush stick, wood stick, crash, splash or riding. But treble lacks sparkle of the HD598. Bass extended deep, and the clean mid bass gave room to vocals that sounds much leaner compared to the HD600. But as much detail the Q701’s have, they're a specialized headphone, Japanese media shamelessly advertise the headphones and there's no doubt their music strives with the Q701. Although the flip side is fatiguing, dry, fast decay and indeed artificial with the wrong recording. No doubt a favorable characteristic for medieval renaissance or drum and bass.
     
    The HD600 I believe has so many strengths that it took me 30 minutes  to shelve my Q701’s. There were so many mentions of the HD600’s guilty of the infamous veil, I didn't want the weird mids of the HD598 to touch my beloved vocals. There was so much flak that the entire HD600’s simple truth was the treble recession compared to other headphones. Other than that, all instruments and vocals have such a natural decay, they're smoother and female vocals simply extended into the 1khz area that was overshadowed by the 2khz peak of the Q701. Mid bass isn't just bloomy like the Hd598, but it's thick, detailed and actually so great it's able to cover up the sub bass roll off that I could easily disregard. The HD600 has a hidden sparkle and the treble itself is significant enough to balance out the warmth and not show any sort of sibilance.
     
    Ideally I wouldn't be able to recommend the HD600 for competitive gaming because of its lack of forward and rear soundstage. I'd say I recommend it now because valve has created the HRTF headphones setting for counterstrike global offensive. All it does is muffle rear sounds and create a wider soundstage that is not usable with the Q701 because of its already large soundstage. But the HD600’s soundstage and imaging is cohesive compared to a Q701. Some people say the hd600 has a small soundstage, I disagree. I've heard the hd800 before and I can simply say that kind of soundstage is enjoyable, but way too big. Others of course may disagree.
     
    One of the absolute amazing feature of the HD600 is that it is modular. I can replace the headband, headband foam,ear cups, the shell, the cable, the driver, the inner foam of the ear cups that I replaced with pantyhose to give the headphone a luxuriously spacious feeling. All without using tools. It feels so much lighter than the Q701 too. But I wish my headphones were new, because I would have liked the stronger clamp. The other name for these are the snapheiser, and for that I won't risk trying to bend these back.
     
    The HD600 is not dark and not too warm. Trust me, take it from a bright headphone user who is satisfied with a JDS Labs ODAC/O2 pairing of an ER4S or Q701. I can also gladly run them off my Sony C4 phone and it will not disappoint. However the HD600’s are definitely capable of equipment scaling.
     
    My headphone search has ended, so you could possibly end yours with an HD600.
    trellus likes this.
  5. Silicone
    5.0/5,
    "Amazing, neutral, clear sound"
    Pros - Clear, neutral, amazing sound, comfortable, everything is right about them.
    Cons - You need an amp to get the best from them. (Subjective) - Clamp is decently tight.
    They are AMAZING headphones, if you like neutrality and clear audio, there is really no competitor, Grados 325e? Not even close, Audio technica r70x? You're kidding me.
    I can't emphasize enough, YOU NEED THESE HEADPHONES, they make sub-par songs sound great, you will love them, no matter how expensive your current headphones are. No more needs to be said....
     
     
     
     
     
     
     
     
     
     
     
    HURRY UP AND GET THEM!
  6. tonglongjeff
    5.0/5,
    "HD600 - Reference couldn’t sound better"
    Pros - Clear highs, rich and pronounced mids, tight accurate bass and sub bass, fully modular, price
    Cons - Proprietary cable, dated design
    Firstly let me just say that out of everything I own and have currently owned. The HD600s are my favourite in terms of sound. The headphones may have a high impedance, but they are not that hard to drive. Pretty much anything makes this beauty shine, and that’s what makes it great.
     
    I purchased this headphone new from a local store in NZ. I got them pretty cheap (used to work there). I got them for $370NZD or around $250USD with current conversion. I WOULD HAVE PAID SO MUCH MORE if I knew the sound that came out of these headphones.
     
    The HD600s are the type of headphones that make you listen to everything you’ve ever listen to again because it’s how it should have sounded at the time. I literally stayed up 4-5 hours the night I got them and skimmed through my library listening to everything. It was a revelation.
     
    Now, I know there are a lot of reviews on this headphone already, so I won’t bore you with the origins and where it was made, who it was made for jazz. I’ll get down to the build, comfort and sound quality.
     
    Build:
     
    The majority of this headphone is made from plastic, whether it be the speckled stone kind or the industrial black kind. This doesn’t make the headphone feel cheap however. The build is quite precise and is great in my opinion for the price of the unit. I would much rather a company put money and effort tuning the sound than making a headphone out of metals for example.
     
    The HD600s are very well put together. The biggest advantage of this type of build is the modularity and modability. Every part of the headphone, excluding the drive itself of course, can be disassembled by the owner and replaced if broken. I’ve read about broken headbands and cracking of plastic. I have not had this experience myself, but if I had I feel much more safe in the fact that I can fix the headphone myself if it is out of warranty.
     
    The build is accurate and durable where it counts. The size adjustment is hard to move, clicky and metal. The pivots for the earpieces themselves are sturdy and strong. The terminals for the wires are also very accurate so that you can’t mix the cables when putting them in. Though I do have a gripe about them being proprietary.
     
    Comfort:
     
    Coming from the HD280s the HD600s were like clouds. Honestly the squeeze of the older monitoring cans could have burst watermelons.
     
    The HD600 I can understand have slightly more clamp force than a lot of other headphones. For example compared to my HE-400i’s and TH-X00’s which are much lighter and more comfortable in comparison. This isn’t to say these aren’t though!
     
    The HD600’s feel SECURE on your head. I’m not afraid to walk around or bend down to pick something up while wearing them. I’m not afraid they are going to fall off my head and break on the floor; something I would never do with the HD800s. I would happily wear these cans for a long session and have done so :)
     
    The velour pads are super comfortable. They don’t feel hot and they don’t sweat after long listening sessions. The pivot and adjustability of the headphones are more than enough to fit a wide variety of different head shapes. The ear cups are large and accommodating without my ears hitting the inside or getting squashed.
     
    Gripes. I know a lot of people like the headband. I think it isn’t bad at all. However when I wore them for extended periods of time, I began to feel the lumps on the top of my head. They begin feeling hard over time. Not physically, it must be in my mind but it does get noticeable.
     
    Sound Quality:
     
    What most people do and should care about :)
     
    The HD600s can be best described as caramel going into your ears. I know the mental image of this does not seem appealing at all but the sound is just so warm and rich! Boring music sounds lively. Even classical music can be enjoyed in a slow relaxed manner on these headphones.
     
    Treble:
     
    I won’t lie, the treble is rolled off a bit. It isn’t as sparkly clear as it’s bigger brothers the HD700 and HD800. However this isn’t a bad thing. Not everyone wants to hear piercing highs all the time. This headphone still has clear precise highs, but they know when to stop. They stop before it gets fatiguing to listen to. I can honestly say this is why I always come back to these. They give such a relaxed and pleasant listening experience.
     
    Mids:
     
    The mids are very well pronounced. Vocals sound amazing on this headphone and it sounds cheesy I know, but it makes voices sound so real and human. This headphone preserves the personality in music. Something a lot of flat monitoring can just take away.
     
    Bass:
     
    I’m a young guy, I like my bass haha. This headphone has plenty!
     
    The bass it clean, tight and punchy. However there is also decent sub bass. The overall timbre of sound is enriched by the low end of this headphone. It doesn't colour the music as much as you think, but it does give whatever you’re listening to some heart and soul.
     
    Soundstage:
     
    The soundstage of this headphone isn’t that big. Picture an oval 10-20% larger than your head around your head and sounds can come from anywhere in that area. For enjoying music this headphone is great. However I wouldn’t use them to experience an orchestra.
     
    Imaging:
     
    The soundstage might be smaller than some other headphones. But the area it does have to play around with, it does so accurately. You can clearly pinpoint where sounds are coming from.
     
    Conclusion:
     
    For the price, or even for more than the price (especially what I paid) you get an amazing set of headphones. The type of sound that makes you question all your listening before these.
     
    It’s affordable enough for even poor students (me) to get into the audiophile game. While giving so much in return. This is definitely deserving of the second spot for headphones :)
    proedros and stalepie like this.
  7. alexdi
    5.0/5,
    "HD600 vs. Many Other Headphones"
    Pros - The benchmark for everything else
    Cons - Intrinsic design elements (i.e., they're open), underrated because they've been around forever
    If this is your first foray into high-end audio, you're listening at home, and you can afford a decent amplifier, buy these cans before you splurge for any others.

    Let me first attempt to burnish my credibility. I've had my HD600s for a few weeks. I'm not Steve Guttenberg and I haven't heard every system on earth. I have installed a number of 4-figure 7.1 systems, designed and installed my own room correction, and annoyed the Magnolia people at Best Buy by spending way too long running my own demo material through 5-figure Martin Logan electrostats. Also, I didn't spend my youth at KISS concerts, so at least for now, I'm not deaf.

    Some cans I've owned or still own:

    Grado SR80 (open, dynamic, $100)
    Sony MDR-7506 (closed, dynamic, $100)
    Oppo PM3 (closed, orthodynamic, $400)
    Hifiman 400i (open, orthodynamic, $500)

    I compared all of them back to back with these HD600s for many hours through a huge variety of well-recorded material, in all cases with an O2/ODAC. This latter component has ruler-flat response and zero audible distortion; I'm not messing with the output with anything that might favor one can at the expense of another.

    My short take is this: start with these HD600s. Mixing, pleasure listening, whatever; if your environment allows for open cans, start here. Nothing cheaper is a more complete product in aggregate. You can spend more and get improvements in some areas, but almost always with commensurate disadvantages elsewhere. Plenty of folks with $1500 HD800s keep their HD600s anyway for when they get tired of the pointed treble of that otherwise stellar can. Orthodynamics and electrostats will top them in the midrange and highs, but often lose on bass impact.

    Start with the HD600 so you can find out what you like. Because it's been around for 20 years as an audiophile benchmark that everyone's heard, you can find endless measurements and comparisons. A sentence that starts with, "I like my HD600 except for ..." is likely to bear more fruit than any other reference.

    That in mind, let's talk about how they're designed and how they compare with the others above.
     
    OPEN VS. CLOSED:

    Headphones are just small speakers. With any speaker, you only want to hear one side. The other side makes the same noise at the same volume, but reversed in phase. If you could magically direct both sides at each other, they'd cancel out. (This is incidentally why it's important not to wire a channel backwards in your home stereo. Weird frequency nulls ensue.) We therefore need to do something with the reversed signal so it won't pollute the primary.

    Closed cans (and conventional box speakers) cover the back of the driver with baffling material to absorb the sound energy. While this approach doesn't want for accuracy or frequency response, it does tend to make the listening space sound smaller. Open headphones (and "infinite baffle" speakers) solve the baffling problem by not solving it; they just vent the back of the speaker into a huge space. Great for acoustics (no need to account for backpressure and the like), but at the cost of treating the missionary one seat over to your collection of Eazy-E.

    Sennheiser assumes you're listening at home with this can, so they've opted for an open design.

    SOUND AND COMFORT:

    Comfort is excellent. I have a big head and big ears. There's a lot of compression and I had to stretch the band a bit. After that, the light weight and plush cups that actually fit around my ears were easy to forget. The SR-80 are on-ear and uncomfortable, the PM3 are on-ear (for me) and very uncomfortable, the 7506 are on-ear and equally comfortable (because they have no clamping pressure), and the 400i are over-ear and equally comfortable.

    Treble is very good. Clean, not strident, and neutral or very slightly forward. On par or better than the 400i for most material. The PM3 is noticeably recessed, but otherwise excellent. The 7506 has a somewhat forward mix with at least one frequency peak that can make it sound thin. The SR80 is quite sharp and tiring with trumpets, violins, and so on. This same treble overemphasis can add life to otherwise dull recordings.

    Midrange is excellent. The 7506 sounds fairly good, but a bit "fake" and radio-ish back-to-back with the others. The SR80 has a large emphasis here suited to solo vocals, but becomes fatiguing quickly on any recording with more than a few things going on, particularly modern rock or pop. The 400i is stellar. The PM3 is almost as stellar, though ever-so-slightly colored. The HD600 has a very subtle, pleasing coloration I didn't catch until I equalized it. Detail resolution is slightly behind the orthos.

    Bass is excellent. Both orthos play a little deeper and with better definition, but lack the HD600's "punch." The 7506 is decent here. The SR-80 might as well not have bass at all. There's a definite argument for the PM3; I might even prefer that one because, like all good orthos and unlike conventional dynamics, there's less distortion at low frequencies. Very pure, distinct tones.

    My best description of the HD600 is "euphonic." There's nothing wrong with the sound. It doesn't sparkle or pound, or whatever wine-review description accompanies cans that try too hard. It's the kind of sound that makes you wonder where the last three hours went.

    FILES AND DACS:

    You can't talk about an output device without a parallel discussion about the signal chain. That includes your audio file, a DAC, and an amp.

    The importance of file format is overrated. No one's ever been able to reliably tell the difference between 44 KHz / 16-bit CD "Redbook" audio and any ostensibly better (e.g., SACD, DVD-A) digital format. Surround sound and the limited dynamic range of analog records might be pleasing to some folks, but for pure 2-channel listening, there's no point chasing anything better than a CD .

    In fact, even lossy compression may suffice. Much of the vitriol directed at lossy file formats stems from bad encoders. If you converted your CDs to MP3 at low bitrates with whatever terrible encoder we had fifteen years ago, you'll probably catch some noises you won't like in some material (e.g., a subtle warble in the ring of a cymbal). But modern 256 Kb/s AAC (Apple's preferred format) or 320 Kb/s MP3 encoded in the last five years? The confluence of factors necessary to be able to distinguish it from the original source (trained listener, good hearing, great gear, isolated sound, repeated listening, looking for that specific flaw) is so rare as to be irrelevant.

    DACs (digital to analog converters) take your MP3, FLAC, MP4, or whatever digital signal and convert it to an analog signal that can be amplified. They're not that complicated; this conversion is very much a solved problem. Or would be if not for the lack of a line-out to skip the amplifier stage in most audio devices, or the tendency to bury the poor DAC among other noisy components that pollute the sound (read: every motherboard ever). If you decide you want a separate one, anything actually labeled as a DAC (ODAC, Modi, whatever) is fine. I spent a lot on an ODAC because it measures well enough never to need upgrading, but honestly, you could replace it with a $30 Fiio DAC and I might not notice.
     
    AMPS:

    Amps have one primary purpose: make the cans play loud enough. Your laptop, phone, iPod, and sound card all have amps already. Whether any particular amp/headphone combination plays loud depends on the sensitivity (dB/mW) of the headphones, their "ohm" rating (their input impedance; the electric equivalent of backpressure), and how much power the amp can output at that ohm rating. Cans with low impedance (e.g., 20-30 ohms) and high sensitivity (100+ dB/mW) are easy to drive. You could run them to deafening volumes off an iPod. Higher impedance cans, not so much. These HD600s have high impedance (300+ ohms) and middling sensitivity. They need more power. They need an external amp, whether portable and battery-powered or a metal box at home.

    Just for kicks, let's do some math to prove the point. Loudness is all about decibels. Deafening is 120 dB, loud is 90 dB, and libraries are 40 dB. On this scale, things sound twice as loud every +10 dB, but every +3 dB needs double the power. You probably want to be able to hit at least 110 dB for transients. Maybe 115 dB if you don't like your spouse and want to never hear them again.

    The iPhone 6 has pretty typical power output for a portable:

    Driving 15 ohms: 45 mW
    Driving 30 ohms: 25 mW
    Driving 300 ohms: 3 mW

    The scale is linear: double the ohm load and you (in physics land with spherical cows and amps that don't run out of current or voltage) cut the output wattage in half. These HD600s are 300ish ohms with sensitivity around 97 dB/mW. The iPhone manages 3 mW for a load like this, so we're looking at maybe 101 dB max. Weak sauce, particularly since that's the loudest possible volume and the average volume for most recordings (that aren't Metallica) will be quite a lot lower. (If you raise the average levels with a maxed-out amp, the peaks won't get any louder, but they will clip and distort.) Compare the PM3: that one does 101 dB/mW with impedance around 30 ohms. With 25 mW from the iPhone, we end up at 115 dB; much more potent. You'd need 60 mW at 300 ohms (about 25 times as much power) to get the same volume out of the HD600.

    After power, the next challenge for the amp is to not ruin frequency response. That's hard for one big reason: the impedance of dynamic headphones (all of them unless labeled orthodynamic or electrostatic) changes with frequency. It might be 200 ohms at this frequency and 400 ohms at another. If the amp's output impedance is zero, that doesn't matter. If it's more than zero, the voltage sent to the cans (and by implication how loud they are at that frequency) will change over the frequency range. Whatever response curve Sennheiser had in mind ("Ve shall haf 14% less zeebilance"), high output impedance can result in something very different. This is why it's hard to take subjective opinions seriously if you don't know how the headphones were driven.

    There's another benefit to low output impedance: better bass control. Speakers tend to get sloppy and distort with frequencies near their resonance peaks. That manifests as a muddy, definition-smothering bass hump. The best way to prevent this distortion is with electrical damping, the ability of the amp to electrically prevent unwanted movement (in the same way that it's hard to spin a motor if you've shorted the power terminals). To keep the bass tight and changes in frequency response inaudible, the amp impedance needs to be, if not zero, at least 8 times less than the headphone impedance. A few inexpensive devices pull this off with just about every can (e.g., the original Sansa Clip+ that measures 1 ohm), though not many (the various iPhones tend to be 5-10 ohms).

    Everything else about amps starts to get subjective. To me, the perfect amp has zero distortion. To the folks buying tube amps, distortion is the whole point. Same thing with deviations to the frequency response curve; best-case, it's flat over the entire range, but if the "house curve" of your headphones is the typical V-shape with an emphasis on bass and treble, an amp that rolls both ends will make the cans an easier listen over the long term. Tube amps usually attenuate the high end; since the classic "audiophile" curve has strong treble to emphasize detail, softening that treble peak quite often sounds better.

    Anyway, long story short, if the open design of these HD600s didn't already to consign them to home use, their high impedance almost certainly will unless you want to supplement your traveling kit with something like a Fiio E07K.

    HD600 vs. HD650:

    The HD600 is one of the most neutral headphones available. Everyone says that about speakers they're used to that don't have glaring response anomalies (and sometimes even if they do), but it's true here: the correction to flatten the HD600's frequency curve is minimal. Music tends to be mastered with a neutral output device in mind; if your hearing isn't unusual, neutral cans are likely to sound good over the broadest cross-section of material.

    The HD650 is the same experience less some treble. It's constructed almost identically to the HD600; the $100 price difference is a marketing maneuver that has nothing to do with sound quality. Rolling the treble lends a "warmer" and slightly less detailed sound that'll flatter music mastered "hot" or with excessive treble or bass equalization. ("Warm" in audiophile parlance is akin to warm and fuzzy; "hot" mastering implies that the sound engineer compressed the dynamic range to make everything loud.) The HD650 also won't draw quite as much attention to themselves. Whether that's better is personal preference. The HD700 and HD800 take the opposite approach: you're getting detail whether you want it or not.
     
    Incidentally, not all "detail" is the same. Detail comes from boosted treble or better drivers. Lesser cans favor treble. Bumping the high range sounds clear and vivid on first listen, but quickly becomes fatiguing. (Bose speaker demos are notorious for this.) Better cans opt for more powerful, higher-impedance, lower-distortion drivers (or different technologies entirely as with electrostats) so intrinsically revealing that the manufacturer can use a more relaxed tone curve. The most detailed dynamic cans (i.e., the HD800) have only a mild treble bump. Less, even, than the HD700, which makes do with a less sophisticated driver. It's unsurprising, then, that reviewers tend to find the HD700 a little harsh on direct comparison.

    You could achieve the HD650's sound by plugging the HD600 into tubes, but if that's really what you want, there's a better way.

    SIGNAL PROCESSING:

    Here we enter controversy. Audiophile purists believe in maintaining the integrity of the signal from recording to output. 24-bit audio, SAC-D, fancy cables, and giant Class A furnace amps are not out of place in this crowd. I respect the motivations for that view, but I've abandoned it with the HD600 for the better. We've had enormous advances in signal processing over the last twenty years. The HD600 is a mechanical device. It doesn't, and can't, have an perfectly flat frequency response. The cups and driver enclosure impact the sound too much, even if the driver itself could be made perfect, which it can't.

    But if we measure the curve, we can recreate any frequency response we want by digitally modifying the input. This is DSP: digital signal processing. The software equalizer in iTunes is a basic DSP, as is Autotune and every "enhance" button you've ever seen in a music player. The processing is almost never "free" (in the sense that it'll only have positive effects), but the benefits can vastly outweigh the downsides.

    To jump straight to the point, a company called Sonarworks has measured and corrected the HD600. The plugin is about $70 from them, and in addition to making the HD600 a legitimate tool for mastering, it also improves ordinary listening sessions quite a lot. Bass impact in particular, always a weak point with headphones, sounds speaker-like through it. The Sonarworks VST plugin works through a VST-supporting player like J-River Media Jukebox or any of a dozen VST hosts (e.g, Audio Hijack on Mac). If you don't like the result, you can emulate a variety of other headphones. Grado GS1000? Sure. HD650? Yep. I hate spending money on things that aren't hardware, but in this case, I'm sold.

    It gets better. After you've installed that, download Wave Arts Panorama5. It's a very powerful binaural emulator that'll take recordings out of your head and put the singer in front of you. Real binaural recordings use a dummy head with physical ears to create positioning cues that can sound wildly more realistic. Panorama (and free, albeit much inferior alternatives like 4Front and Psypan) use HRTFs (head-related transfer functions) to modify a conventional signal with math to recreate the dummy head effect. Done well and matched to your ears, it can leave you agog. ("Why is my neighbor pounding on the ceiling? Oh. Wait.") Likewise a program called "Out of Your Head," which is expensive because the author measured a bunch of high-dollar audio setups. Want your HD600s to sound (exactly) like a movie theater? That's now a thing.

    IN SUM:

    To wrap this novel: definitely try the HD600s. They're frequently on sale in the low $200s. There isn't anything as good anywhere near that price. To give perspective, after demoing them against the 400i for a month, an ortho at twice the price that everyone raves about, I returned the 400i. But I'm a home listener. If you're on the go, have small ears, and don't want to annoy everyone, try the Oppo PM3 instead. Truly, you can't go wrong with either.
    PinkyPowers, trellus and cpauya like this.
  8. GLXLR
    5.0/5,
    "Wonderful headphones that every audiophile should own"
    Pros - Soundstage is unparalleled, comfortable, smooth mids and treble, punchy bass,build quality, replaceable parts, tons of custom parts,
    Cons - Possibly too smooth for some, pattern on headphone can sometimes come off
    I hope every person looking into audio gear picks up an HD600. I really understand why it is a classic headphone and how even decades after its launch, it is still considered one of the best headphones you can get. In my opinion the best part of the headphone is its sound stage and positioning. While not super wide, it is super easy to determine where instruments and where they are relative to each other. Also the headphone is not extremely hard to drive and because of its popularity there are hundreds of amps that were designed with this headphone in mind. 

    Here is a link to my video review on youtube that goes a little more in depth: 
    https://www.youtube.com/watch?v=oqr62LqnGyw
  9. xevman
    5.0/5,
    "It doesn't get much better than this"
    Pros - Sound signature smoth fatigue free sound while still remaining fairly detailed, Fully modular design
    Cons - Not overly flashy the build doesn't really match the price, Bass doesn't extend overly low, Standard cable should be better
    In my humble opinion the Sennheiser HD600 is by far one of the best sounding dynamic headphones on the market period hopefully you'll agree with me at the end of this review.

    Specifications
     
    12 - 39000 Hz
    97 dB at 1 mW
    0,1 %
    ca. 2,5 N
    circumaural
    3,5/6,3 mm stereo
    3 m
    open, dynamic
    300 Ω
    260 g

    Nothing really much to see here other then the fact this is a very high impedance headphone with a moderate sensitivity which means this headphone clearly NEEDS good amplification. Self powered small USB dac/headphone amplifiers can drive this headphone fine however for the best experience I recommend at least a Schiit Magni or O2 as both these amplifiers swing plenty of current into a high impedance load. These headphones will play well out of a receiver (as long as its a resistor based headphone out not opamp), integrated amplifier and preamp aswell (I've used it on my vintage mid 70s era Sansui integrated amp and it drives the headphone very well to extremely loud levels too). If tubes are your thing these match perfectly with all OTL Tube Amplifiers due to their high impedance.

    Build
    The Sennheiser HD600 is a unique headphone in the way that every part can easily be removed and replaced and spares are readily available and when I mean every part I literally mean everything, you don't even need any special tools to disassemble it everything just snaps together. Fit and finish are really nothing to write home about, it seems durable enough never had issue with my headband cracking/snapping (which is supposedly an issue) I've had the headphones for a while and im not precious with them either. The overall build quality is fine and it does the job, it isnt spectacular by any means especially at this price point. The standard cable is pretty lame I destroyed mine in just a few months (the part that connects to the earpiece). Replace this with a HD650 cable which is much more solid and better made cable and no before you ask it does nothing for the sound don't try to tell me otherwise I don't believe headphone cables make any tangible difference, although don't let it stop you spending 5 or 10 bills on a custom cable though if that helps you sleep at night.

    Comfort:
    If you can get over the initial clamping force that goes away slowly with time these are a very comfortable headphone the pads are soft and plush and feel good on the head. You can hardly feel the headband on your head there is no pressure points there other then the clamping around the ear. People stretch the headband to help loosen clamping force but I do not recommend this as its not needed and you can potentially break it. It will go away with time.

    Sound:
    The Sennheiser's sound signature can be described as neutral with a slight warm tilt although not overly rolled off at all. Its a smooth sounding and forgiving headphone not fatiguing to listen to in the slightest but still remains detailed enough to be somewhat analytical (Which the 650s don't do IMO).The bass is good just don't expect it to extend super low, Its right were it should be not overly abundant but enough for the headphone to not sound anemic in the slightest. This is why to me the HD600 to strike the perfect tonal balance for a headphone.The 'veiled' term used by some to describe these headphones a load or rubbish and anyone that believes in this probably listens to obscenely bright headphones. Soundstage is good but not amazing for open headphones if you want a headphone with a superior soundstage have a look at the K7xx line of headphones or step up to the HD800 which especially the latter offer a massive sound stage. 

    Ill give you my listening experience with my 3 amplifiers source is music files from my PC -> Optical in to my DacMagic 100

    Woo Audio WA6
    If I blindfolded you you probably wouldn't be able to tell this is a tube amplifier. The HD600s sounded great for this amp however the low end wasnt as present or as tight as it was with my other solid state amplifiers. Highs where crisp and clean nothing rolled off and mids were present with great punch and clarity. There really isnt that much more say about this amplifier. If I had a bottlehead crack or Woo Audio WA3 there would have been much more to say and made for a more interesting comparison as these are both OTL which greatly alters the sound signature.

    O2
    The wire with gain as people call it again nothing really much to say here either the HD600s paired wonderfully plenty of power to drive these cans with ear shattering levels. Bass was more prevalent on this amplifier then on the Woo (probably due to the higher dampening factor). Mids and highs seemed very similar, so similar infact the only difference I could pick was that the highs seemed to be more prevalent on this amp but thats not to say that the Woo rolls off the higher frequencies that would be an exaggeration, best way to describe it would be slightly smoother sounding.

    Gustard H10 (modified v200 clone)
    Pairs excellently with this amplifier. Bass was very controlled and tight and more prevalent then on the O2 (which would make sense as people describe the V200 as a warm sounding solid state amplifier) other then that it was very very similar to the O2 across the rest of the frequency spectrum. Keep in mind this amp is complete overkill for these headphones.

    The HD 600 is a forgiving headphone but at the same time is still detailed enough to give you an accurate portrayal of whatever it is you are listening to. As you can clearly see it does everything rather right and that's a big call to make as its very hard to find a headphone you can actually say this about. No headphone is perfect even top of the line flagships which cost many times more then this. The HD 600 isn't perfect either but for the price point this headphone is available for its as close to perfect as you can get.
    Hal X, PedroVazquez53 and Pokemonn like this.
  10. Asavage
    5.0/5,
    "Sennheiser HD 600 (For lack of a more creative title)"
    Pros - Very Comfortable both sonically and physically
    Cons - Outdated aesthetics (personal preference), Long burn in time.
    Dear Head-Fi community,
     
    By the time you get to my short review I am sure you have read many other reviews for this popular set of cans. So without elaborating on the wonderful mids, the neutral sound, or great soundstage I would like to share my favorite attribute of these wonderful cans. These of all my cans I keep coming back to even though I have superior headphones. I find they are the most sonically comfortable for extended listening of any of my headphones and I find myself shelving my Beyerdynamic t1s and Audeze in favor of my HD 600s during a long project for quiet background noise. I recognize that in nearly every aspect the other cans sound better and I do prefer them for serious listening and movies. But something about my HD 600s makes the very comfortable to listen softly for hours at a time. In order to try and quantify this preference I have tried several different cables and light modding. Following this I discovered that the only thing that seemed to affect this attribute was the simple foam mod (removing 4 pieces of foam around the driver. At first I noticed that the Sennheiser veil that many people complain about was lifted and I seemed to get a better bass and treble response, however after a long session I discovered that I could no longer wear them for extended periods like I could before. With most things headphones things become very subjective, however if you are considering these awesome headphones don't be afraid to give these a shot because they will never leave you tired or strained.