This is a review and detailed measurements of the Sennheiser HD 800 S. A very kind member sent these months ago and has been patiently waiting for their review. The HD 800 S costs US $1,700 but I see it on Amazon for US $1,323 including Prime shipping.
The HD800S is at the same time solid but also very light:
View attachment 99381
I was surprised how they just melted on my head the moment I put them on. In contrast I feel the pressure of other headphones for a while until my brain starts to filter it out. The massive cups mean that they fit optimally almost no matter how to throw them on your head or the measurement gear. I did not feel that they were loose but I see some people complaining that the fit my be so.
I like to have a long headphone cord as I move around but then worry about them getting chewed up under my feet. Sennheiser seems to have solved this problem by creating a cord that while very long, feels super robust and doesn't seem to weigh much:
View attachment 99382
The 1/4 inch termination is wonderful. I imaging $50 of the cost went to that!
Other than the high cost, I don't know that there is much to complain about here.
The measurements you are about to see are made using a
standardized Gras 45C. I searched for any and all measurements I could find online. Alas while a number of them are close to mine, none are using the exact fixture down to coupler and pinna. As you will see, I have confirmed the approximate accuracy of the measurements using Equalization and listening tests. Ultimately headphone measurements are less exact than speakers above a few kilohertz so keep that in mind as you read these tests.
I have calibrated my headphone fixture with 94 dBSPL test tones and decided that I use the same for headphone measurements. However, instead of using 1 kHz tone I have opted for 425 Hz. This seems to better match research data.
I have also made a lot of progress in building a better test suite for the measurements. More updates and changes will be coming but I am starting to feel good about this set.
Sennheiser HD800S Measurements
There is nothing more important than frequency response of the headphone as each is seemingly different and that difference leaves a very distinct character:
View attachment 99383
The dashed line is the target I am after. As we clearly see the HD800S doesn't even maintain its flat response let alone have the preferred bass boost. This will throw off the balance of the headphone and make it sound light and potentially bright. The next area of significant departure is post 1 kHz. The curve is distinctly below our target until about 5 kHz where it takes the other direction and shoots up a bit over our target. Around 9 kHz and up we have a lot of reflections inside the cups so ignore those ups and downs. I evaluate that area perceptually in the listening test. So overall, not a good showing.
I will do more work in the future to sensitivity but for now I am just reporting what the drive voltage is to achieve the 94 dBSPL reference. As I note later, 94 dBSPL is rather quiet so don't get confused thinking 0.26 volts is all you need to drive this headphone. But as a reference it should do to make comparison against other headphones.
In case you are doubting the reference curve and as a way of comparison, let's measure the Sennheiser HD650 headphone:
View attachment 99384
We see that bass performance is similar but even more anemic in lowest register (although that may be a fit issue -- I did not try to optimize the 650 as much as I did with 800S). From 150 Hz up though the HD650 hugs the curve very well and has none of the deficiencies of the 800S between 1 and 4 kHz. No wonder it is such a popular choice. The HD800S does have more energy at or above 5 kHz. This may be behind its spatial qualities that I will talk about in listening tests.
Next up is distortion measurements. I kept wondering why my speaker distortion measurements were so revealing and the headphone ones were not. I realized that it was all in the presentation of the data (and its optimization). So I mimicked what I had done with Kilippel using Audio Precision software I am using and results snapped into clarity:
View attachment 99387
As with speaker testing I am showing the THD percentage at two output levels: 94 dBSPL and then 104 dBSPL. Note the highly non-linear increase in bass distortion which is what we see in speakers as well. Let's compare the 104 dBSPL against HD650 again:
View attachment 99388
It is a mixed picture with accuracy not being super high but it seems to me that the HD650s settles to lower distortion sooner than HD800s. Overall picture is the same though. We will learn more as we test other headpones.
As with speakers, let's also look at distortion level as opposed to percentage:
View attachment 99389
For some reason I can't get this specific graph to show more harmonics. Based on what is there, 2nd harmonic dominates most of the time except for the region between 100 and 300 Hz where 3rd harmonic becomes highest.
Sennheiser HD800S Listening Tests
As I noted, the best way to know if our preference curve is correct is to try to approach and see if the subjective results are better. So let's do that:
View attachment 99391
I have eliminated the headroom allowance to make the graph easier to read. In reality I had to dial in 6 or more dBs depending on what I was playing to avoid digital clipping. You have a trade off between how much you boost the bass and the headroom you need to allow. I love the clean presentation of deep bass from headphones so dialed in what the preference graph said and results were excellent. My "speaker killer" tracks with their sub bass sounded wonderful. Despite the sharp rise in the distortion graphs, there was no penalty that I could detect in that department despite the high level of boost.
Next job was to fill the gap between 1 and 4 kHz. That is a complex shape to fill in but I approximating it by putting in the conjugate filter to knock off the resonance peak at 5.4 kHz. Once there, I thought the result was a bit bright. A quick shelving filter of 10 kHz solved that problem nicely.
The overall tonality was still "light on its feet" for lack of a better phrase to describe it. There was this lack of congestion and ease to everything I played. What was remarkable and uncanny was separation of instruments. It was as if this headphone would take every element in the music, pull it apart, and then position it in different spatial locations in a 6 inch space around each ear. I wouldn't call it "soundstage" as much was it was this fun and captivating effect.
I made a comparison against the HD650 which sounded far more balanced and nicer than HD800S without EQ. With EQ, the HD800S sounded a lot more competitive and that had the above layering that the HD650 did not have. I played by boosting the region in the HD800S that has peaking and that seemed to help create a bit of that effect. Likely the cup size and reflections in HD800S are creating this effect.
Here is a great track to use to test the above effect:
This track just sounds stunning with the HD800S and above equalization. There is deep bass, wonderfully clean highs and that great instrument separation.
Conclusions
The Sennheiser HD800S has great build but comes up way short in tonality. It is light in bass which is typical of many headphones but also cheats us the energy between 1 and 4 kHz. I paid for all the tonality in my music and I want all of it reproduced darn it! Fortunately equalization works despite the massive amount of amplification required in low frequencies. Once there, this headphone is doing something I don't hear with any speaker system and not yet on any headphone. It manages to provide a spooky layering and I guess I should say clarity that is not only surprisingly but delightful. I don't know if the effect will be too much if it comes across a lot of music but so far, I can't help but liking it and liking it a lot.
On a comfort side the HD800S is a delight. I find a lot of other headphone confining but not the 800S. Combine this with the post Equalization and you have a headphone I don't want to part with!
If you don't use equalization then this is not a headphone for you. But if you do use it (as you must with any headphone), and can afford it, the HD800S is a delightful way to experience music.
I am going to put The HD 800 S on my recommended list.
------------
As always, questions, comments, recommendations, etc. are welcome.
Any
donations are much appreciated using
: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
