The Brilliant Sennheiser HD 800

The Sennheiser HD 800 ($1499)
I had the good fortune of a factory visit to Sennheiser's campus in Wennebostel, Germany sometime in 2005--four years before the HD 800 made its appearance at the 2009 Consumer Electronics Show, the HD 800 was already heavily under development. We'll never know, of course, but I reckon these headphones have more R&D hours invested in them than any other on the planet. The engineers at Sennheiser were given a "clean slate" to develop the world's best dynamic headphone. At the time of my visit, the dialog mostly centered on developing large diaphragm drivers for dynamic headphones that would deliver a flatter wave-front as it approached the ear and that wouldn't suffer "cone break-up." It was obvious to me they were also having the time of their lives with the whole variety of issues surrounding headphone design, and were up to their necks in all manner of design ideas and visions. Interestingly, the final product was very unlike what I saw on computer screens that day in 2005--the sound, however, is not unlike what I had imagined: simply spectacular.

The Sennheiser HD 800 is a full-size, open headphone with rather large earpieces, which fully, easily, and very comfortably encompass the ears. The ear cushions are a micro-fiber material that is cool and comfortable. An easily removable and hand-washable cloth protector covers the inside of the earpieces. A permanently installed synthetic mesh material covers and protects the driver from dirt and hair. The main earpiece housings are a framework cast of Leona plastic--a 60% glass fiber filled, high stiffness specialized plastic. A very fine acoustically transparent stainless steel mesh is supported by the framework, as well. A bail/gimbal assembly attaches the headband to the rear of each earpiece, and has two pivot points that allow adequate freedom for the earpiece to tilt and swivel to align with the side of the head for a proper fit. The headband has a middle section that includes a comfortable pad made from the same material as the earpads. Sennheiser claims the headband has features that provide a significant amount of vibrational damping. The cable's conductors are OFC (oxygen free copper) in a "Y" configuration, and are attached to each earpiece with some very nice connectors. A large and very nice custom 1/4" stereo headphone plug is at the other end of the cable. There is no 1/4" to 1/8" adapter for use with portable players and the like.

Ring Radiator Driver
sennheiser_HD800_Photo_driverexplodeddiagramThe major technological advance in the Sennheiser HD 800 is the "ring radiator" driver. This driver delivers a couple of advantages: it reduces "cone breakup," which causes distortion at high frequencies; and it provides better imaging by being angled back towards the ears from a slightly forward position thereby emitting a rather more planar wave front than a normal headphones driver.

A regular driver diaphragm has a dome in the middle; the voice coil about half way to the edge; and a surround or suspension outside the voice coil that has a fixed attachment to the driver housing around its outside edge. The problem with this type of driver is that at very high frequencies it may stop acting like a pure piston moving only straight in and out, and may take on additional vibration modes so that the surface is wobbling or twisting as it moves in and out. This is called "cone break-up" in speakers.

The traditional approach to solving this problem is to make the speaker cone, or driver diaphragm in this case, stiffer so it is less likely to begin vibrating on its own. This is where you find folks making aluminum speaker cones, or cones with ridges and various features to make it more rigid. Sennheiser developed its Duofoil diaphragm material (used in many of its high-performance headphones) to combat this problem. Unfortunately this often leads to a heavier cone that is more difficult to accelerate, and therefore lowers the slew rate (transient response) of the driver.

sennheiser_HD800_Photo_wavefrontRecently, another approach appeared commercially, called a "ring radiator." Both Scan-Speak and Vifa produce a version of this type of tweeter. In this case, the driver is not a simple circular driver, but a ring shaped driver which is attached both at its outer circumference and at its inner edge. The diaphragm is driven by the voice coil which is attached behind the "V"-shaped groove halfway between its inner and outer edge. This configuration dramatically increases the amount of structural support for the surface area of the driver, and reduces to amount of surface area that can begin to take on its own vibrations.

Because the new driver could become larger without breaking up, we also get two other sonic benefits: tighter bass and better imaging. A larger driver allows the diaphragm to displace more air for any given unit distance moved compared to a smaller driver. Moving more air means the driver can achieve better bass extension before it runs out of voice coil travel. It's pretty obvious when listening to these cans, they really have an astonishing sense of ease and control in the lows.

sennheiser_HD800_Photo_stereowaveThe second advantage the new ring radiator has in the HD 800 is improved imaging, a better sense of coherence. Normally, sound arriving at your head from a source some distance away is essentially a flat wavefront. With typical dome driver headphones, the sound source is very close to your ears, and the wavefront is still fairly spherical when it hits you outer ear. It is argued, in headphone engineering circles, that the outer ear focuses the two wavefront geometries differently into the ear canal; and that the more curved wavefront of typical headphones causes psycho-acoustic problems resulting in poorer imaging.

With normal speaker listening, the wavefront is hitting the side of your head and ears at an angle. To mimic this geometry, Sennheiser mounts the HD 800 drivers slightly forward of your ears, and slightly angled back towards them. The larger diameter and angled geometry of the HD 800 driver produces a wavefront that arrives at the ears in a more natural way than with traditional headphones and allows more of the normal reflections at the outer ear to occur, which allows the brain to understand and localize the sound it's hearing significantly better. The result is significantly improved imaging.

So, how do they sound?

Sennheiser USA
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(860) 434-9190

inarc's picture

Good review except for your endorsement of recabling snake oil, in my opinion.

Brod's picture

"Good review except for your endorsement of recabling snake oil, in my opinion."

Agreed. Without favourable double blind test results, any assertion that changing cables makes an audible difference is entirely worthless and should be disregarded. It also casts doubt on the rest of the review from an objective POV.

Tyll Hertsens's picture
I'm going to do a review, on onf these days, comparing the stock cable to the Cardas Clear and something from Moon Audio. I'll measure them on the cans ... and it will no doubt show nothing. Then I'll listen subjectively, not blinded, and I'll report my fuzzy, gooie, findings, confirmation bias notwithstanding. Then you ABX guys can rant to your hearts content. I've heard differences in headphone cabling for years; I really think you guys are underestimating the subtlety of human perception.
Graywould's picture

Don't let these schmucks bully your opinion. If he heard a difference in the cable, SO WHAT!!! The truth is not greater because one picks and choose what you awesome is true.. After all, it is his experience. Most likely you have an opinion without any experience, which is the Schmucker kind.
I support his opinion because I have experience. Frankly these headphones weren't that desirable to me untill acurate cabling and power cords were used.. By the way they were not Cardas.

Limp's picture

"Recabling with one of the Cardas headphone cables will provide a slightly smoother experience as well."

Surely you do not expect us to accept such lofty claims without you substantiating them?

Tyll Hertsens's picture
Thanks, I appreciate your comments ... but that's my experience.

I wouldn't characterize "slightly smoother experience" as a lofty claim.

svyr's picture

>I wouldn't characterize "slightly smoother experience" as a lofty claim.

a lot of your audience are measurement believers and remember the ye ole cable tests between copper, silver, xN OFC, and there not seeming to be much difference measurement wise ;) (or at least nothing remotely audible) (from memory those were AES studies, or some thesis papers or something). So we all eagerly await the results to verify it's indeed not placebo in favour of the prettier looking cable in the form of whatever magical properties one thinks it should possess or is perhaps told by the seller it should possess.

drblank's picture

if AES had the proper testing methodology, equipment and/or software to actually test for quality of sound in a cable?

Go talk to Bob Ludwig. Does he hear a difference in audio cables in his mastering studio? He says he does. Am I going to argue with Mr. Ludwig on that subject? NO. I'm not that stupid. He's a member of AES, he's highly regarded as one of the top mastering engineers in the audio world, and he rewired his entire studio with expensive cable because he heard a difference and the difference was enough for him to rip out all of the old cable and to rewire it. Same with SkyWalker Sound, they rewired their studio many years ago with expensive cable as well. There are many other top end recording studios and mastering studios that have bought into the high cable products. Why? Because they heard a difference. They didn't get free cables, they paid cash money (and lots of it) to rewire their studios and these are NOT the type of people that spend gobs of money on expensive cabling just for the heck of it.

I would argue that the AES measurements were probably not the right measurements to begin with.

There is a LOT more to what makes one cable different than just what type of metal is used. That's only one teeny tiny aspect.

You have cable geometry, windings and level of precision of the windings, dielectric used, insulation, termination, etc. etc. and there are some companies that have custom software and/or hardware to measure things most people don't even know about.

You have to look at the harmonic structure of complex wave forms, rise time, sustain, decay of various audio signals throughout the band width, you have to consider time alignment, phase alignment, articulation, etc. etc.

I don't know what specific tests you are referring to, but I've read some thesis paper that was simply a joke, the person didn't even compare any of the more expensive cables on the market. He was comparing only a bunch of relatively cheap cables that probably sound similar enough. When people do ABX tests, some don't even know how to do those. It's almost impossible to set up a proper listening scenario with a switch box where cables are concerned, so ABX tests are almost worthless in comparing cables.

So, either you hear a difference or you don't. if you do and you are willing to spend the money, than that's that person's preference and it's valid to ONLY them. If you don't, then that's your preference. Both are valid only to the specific people making the decision.

So, to you, you think cables are snake oil, where to others it isn't. I've run into audio engineers that also thought NS-10 were uncolored reference speakers, and then I run into experienced mastering engineers that think that NS-10's are worthless garbage. Who would you listen to in that comparison? Are NS-10's junk? Everyone has their own opinion based on their own listening.

Bottom line, if you think cable difference is a myth, go right ahead, there are top recording and mastering engineers that have probably done more top rated albums than you have and THEY say THEY hear a difference enough to spend GOBS of money rewiring their studios. So, I would kind of listen to THEM, rather than some foolish attempt to debunk cables.

I've probably read that same thesis paper you are referring to. To me, it was a joke of a thesis paper and didn't really convince me that there is no difference in sound quality of cables. I've heard differences in cables myself over the years and depending on the situation, it's either VERY noticeable or it isn't. There are simply a lot of factors that will dictate if you hear the differences or not and over what period of time.

Graywould's picture

Microphone DROP!

Limp's picture

It is a lofty claim in that it, as svyr mentions, flies in the face of all research on the subject.
That is unless either of the two cables have electric anomalies severe enough to affect the frequency response of the amplifier/headphone system. If that is the case, why not save a few hundred dollars and spend a minute or two equalizing, say down a bit in the 5-8kHz area, as sibilance seems to be among the biggest complaints?

I guess my question is really: yes, you experience a slightly smoother experience with the Cardas cable, but why is that?

After all, you only have yourself to blame for us to expect some rigour in your testing ;)

svyr's picture

pretty much. the burden of proof of anything beyond 'it looks pretty and durable' (it must sound smoother - my wallet and the insulation layer on the cable definitely feel smoother!) should be heavily on the manufacturer and reflected in objective measurements.

luckily conspiracy theories about bias aside Tyll's just the guy to do it.

Tyll Hertsens's picture
You guys are just going to have to get used to the idea that, while I rely heavily on measurements for some things, I also believe that the human experience can not be fully characterized with objective metrics. I believe my work here is to express my experiences, and that will include opining on product outside of an objective framework.

Yes, I believe there are things we can experience that can't be measured objectively. How many pounds of Joy did you experience yesterday?

Limp's picture

Well, colour me surprised, I never had you down as mystic. Or mysterian, as Owen Flanegan would say.

Ever since I first encountered you on the web, nearly a decade ago, I figured you were of a genuinely enquiring nature. I guess I shouldn't expect too much.

Oh well, enjoy your cables :)

Tyll Hertsens's picture
"Ever since I first encountered you on the web, nearly a decade ago, I figured you were of a genuinely enquiring nature."

Indeed I am. Perhaps you are the one not open minded enough along some lines to be "genuinely enquiring."

A purely deterministic worldview died with a bunch of Viennese physicists a long time ago. What makes you think the full majesty of human's experiencing being is so easily measure with our crude instruments of today?

There's plenty we don't know.

Sennoquitur's picture

Couple items not mentioned elsewhere (and with due respect):

I know I trust Sennheiser's engineers designed and built what they determined to be exactly the right cable for their flagship cans. Why lavish so much attention on the headband and ear cups only to skimp on the cable? Why deliver signal to drivers spent nearly a decade in development over a coat hanger?

I know that no matter how many different cables you hook into the connectors, the signal still travels over that same soldered wire segment running from the connector barrel to the driver. That last few millimeters of wire never changes. Unless you remove the connector barrels and hard solder, all cables connect through them. How can you possibly hear any cable difference passing through that same last wire segment?

I know the stock cable is the perfect length, lightweight, and non-microphonic. For me, that last bit alone dispels any need to try anything else.

mward's picture

Things don't have to be unmeasurable, full stop, to be unmeasurable using current techniques.

Scientifically, I'm totally skeptical of cables. But I've read enough of Tyll's reviews to know that he can hear some things that I can't—and perhaps, that includes differences due to cables.

svyr's picture

meh. never pegged you for a romantic of that sort. Guess curiosity and objectivity have to stop somewhere I suppose. For me not at cognitive biases and placebo relating to audio :)

>Yes, I believe there are things we can experience that can't be measured objectively. How many pounds of Joy did you experience yesterday?

as much joy as oxy, serotonin and dopamine levels have alloted combined with my experiences. Neuroscience approves.

inarc's picture

The sensation of emotions is not some neurotransmitters just as the sensation of colours is not some electromagnetic radiation. See:

While I don't doubt that Tyll perceives cables as making an audible difference, I am strongly convinced, given the current scientific evidence, that this is a psychic phenomenon without a physical basis (i.e., placebo effect).

svyr's picture

> this is a psychic phenomenon without a physical basis (i.e., placebo effect).

which is what we've been saying it is for the past x posts :D...

burnspbesq's picture

You measurement fanatics crack me up.

Subjective impressions are every bit as real to the person experiencing them as anything that y'all can measure with your crude tools.

If I hear a difference in the performance of the HD 800 with the Cardas cable vs. the stock cable, then there is a difference. Period, full stop. God gave me one set of ears, and I choose to trust them because there is no alternative that doesn't come with a side order of silly.

Feel free to continue arguing about meaningless trivia. I'll be over in the corner enjoying my music.

PredatorZ's picture

Preaching to the choir brother. Ill meet you in the listeners corner, enjoying my music !

svyr's picture

>The sensation of emotions is not some neurotransmitters just as the sensation of colours is not some electromagnetic radiation

Well, the process for both is quite well understood from the neurosci point of view - just open any intro psych or neurosi text (especially light perception and transformation/processing). I'm sure placebo can be fitted there as an internal 'stimulus' by virtue of expectation or self-delusion if you wish that either act as stimulus or affect the processing.

Bottom line I wouldn't phrase it like that and point people to a semi-philo long piece on wiki. That seems defensive and obfuscatory to a point.

inarc's picture

Well, no, data processing may be reasonably well understood, but how that data turns into a subjective conscious quality is not. For example, how would you describe the subjective quality of seeing the colour blue to someone who is and was born blind? You could talk all day about wavelengths, receptors, transmitters and neurons, but you would still not have described how seeing blue is and why it is not equal to seeing another colour.
One could even begin on a much more fundamental level, such as consciousness itself (i.e., how it is to be conscious), for which there are currently no clear neural correlates.

Tyll Hertsens's picture
I need a "like" button for this post.
svyr's picture

you seem to want to mix philosophy into neuroscience, I'm not sure it's appropriate :)

inarc's picture

you seem to have a naive understanding of neuroscience, especially cognitive neuroscience :)

svyr's picture

I'm not convinced and suggest you read the corresponding chapter of say Feldman's intro to psychology, and the section relating to senses and in particular the several pages explaining vision and the related sensory and processing attributes.

inarc's picture

Hopping from neuroscience to psychology, but philosophy must be left out as it is, you know, entirely unrelated (philosophy of mind, neurophilosophy, etc.)? :D
I must say, though, that "Essentials of Understanding Psychology" (9th Edition) contains many pretty pictures.

svyr's picture

read the book. or any other source. The biological bits related to receiving the external stimulus and up to the start of the cognitive processing stage are obviously sourced from appropriate neurosci journals and bio related books. (despite being dumbed down for 1st year psy students :D )

That said, the em stimulus signal, up to the start of processing are well understood but you're right, it looks like interpreting the information (visual and associative cortex) doesn't seem to be all that well. (they sorta skim over it saying intepretation of the raw data ultimately involves larger number of brain parts, depends on past experiences, associations, state of mind, and just about everything else incl structural side effects of the areas responsible for the interpretation)

It looks to be a similar story with hearing/processing of audio. (ok, except for some bits in hearing with the two competing theories it describes for hearing different frequencies relating to how sound is converted in the basilar membrane)

That said, the physics behind sound and light, measurement of the stimulus and the physical conversion to electrical signal in from sensory organs look to be well understood. Especially stimulus measurement.

While it's nice to know that you can indeed 'hear delicious placebo' effects and study them through more neuroscience, that's a completely separate issue from there being an actual difference in measurements to the sound produced and as mentioned above. If there's no difference and the manufacturer claims there to be one, that's deceptive and misleading advertising in my book.

KikassAssassin's picture

Have you tried doing a double blind ABX test with different cables? I'd be curious to see if you could tell a difference between them in a properly performed listening test.

Measurements may not be accurate enough to pick up all the differences we can hear, but there are ways of doing objective scientific comparisons that don't involve measurements.