[TenMoonsNorth]

Spoiler

You made the classic mistake of assuming since the HD 800 S bass sounded different than the HD 800, that it must be distorted.

You seem to imply here that in your impression, the HD 800 was "clearer" yet you recognize that the HD 800 S was "more extended". These two things are a bit at odds with each other. Having extended bass means having bass present which means having the overall bass presentation more clear.

A frequency response is good for some things, but you can't just isolate a single section of the frequency response, and assume you can consider that in a vacuum without the rest of the frequency response context. The frequency response represents the overall "tonal balance" of the headphone, and you need to consider the entire thing. In terms of detail retrieval (this includes hearing bass extension, details you never heard before such as background coughing, and so on), part of that is a function of the balance of the frequency response and which frequencies are emphasized in aggregate. You hear that cough because the frequency band the cough exists in is different than the previous sound source you were using. The same is true of bass, bass extension, and so on.

The HD 800 has sections of elevated treble, which can tilt the tonal balance and how you interpret the sound. By tuning the HD 800 S to have less treble, the bass becomes more balanced and potentially clearer and better extended to the listener.

Finally, at the end of the day, everybody needs to understand there are pretty fundamental problems with measurements. They will never be perfect. They are an imperfect tool we can use to try to have a discussion about things, but especially when it comes to bass response, there are a lot of potential issues and problems with putting a headphone on a dummy head and expecting the result to sound exactly the same as when you hear them. People's ear canals are different, different frequencies might be emphasized in your particular HRTF, and so on. It's possible Sennheiser tuned the headphone to a different target HRTF standard than Jude or Tyll's measurement set up.

My advice to anyone, when measurements differentiate from your listening impressions, trust your ears. Your enjoyment of the headphone is the only thing that matters. As a corollary, don't parrot things you hear online and try not to let other people's flawed impressions influence your own. Things like the HD 800 S have zero bass distortion. If you don't like the tonal balance of the HD 800 S, just say that. Don't pretend it has distortion (or, likewise with the HD 660 S, pretend that one has a "grainy treble").

The HD800 and HD800S makes comparisons very easy because how they share the same earpads and geometry.

What is shown on community setups and the innerfidelity setup is the HD800S has more THD at subbass frequencies than the HD800. It's in Jude's FFT measurements that two are very similar at 90dB SPL at 40Hz.

If Jude and Tyll swap headphones and both show the same results as they did before, which is what I think is likely, then the difference is coming from method and more knowledgeable people can argue over that.



1:30 onwards shows the differences between the HD800 and HD800S with flashlight illumination from the back. I expect the fabric hole covering the center and perhaps a slightly different screen behind the driver are the only differences between the HD800 and HD800S.

Spoiler

Again, it's the HD800 measurement in the FFT I'm most interested in, for a couple of reasons. First of all, I think it's the one from which this discussion originated. I'm not sure which of the HD800 serial numbers it was (as both of the ones from that post's measurement booklet do show as having been modified, one of them several times). Second, that FFT shows the HD800 as having higher H3 than H2, and it's labeled "HD 800 DP Mod" (see the red and white arrows below), and this (H3 > H2) seems to be the reason for the biggest difference (and the resultant theory).



As I've said before, I am not saying the HD800 in this FFT was modded -- I'm only pointing out that it was marked as "HD 800 DP Mod," so I think it reasonable to point out.

If you look at the HD800 that is being modded (in the video) with the resonator mod, the HD800 had seen at least one prior round of modifications (as mentioned around 6:45 in the video), and as is clear from the view around the driver:



Here's one that has had no driver or damping modifications performed on it (S/N 00342):



Again, while the FFT in question says "HD 800 DP Mod," I can not confirm whether or not that measurement reflects a modified HD800, a stock-and-never-before-modified HD800, or a modified-and-restored-to-stock HD800. Only InnerFidelity can clarify that.

As I said, so far we have measured two HD800's, both of which have noticeably higher H2 than H3 at varying drive levels. More are incoming, and we'll measure them all -- and perhaps we'll come across one that also has higher H3 than H2.

As for the other InnerFidelity HD800 measurements you linked to, I noticed something in common with all of them (whether modified or unmodified HD800's), in varying degrees, but never insignificant. In all of them there are large spikes at 200 Hz and 2 kHz. Here's what I'm talking about (arrow pointing to the spikes in question):




I am rather certain those are not from the headphone, but from the system, and I do not know how (if at all) whatever is causing those spikes would affect the THD readings. Also, they do not appear on the FFT.

---

Almost all of the other measurements I have seen have come from DIY measurement systems, most probably having been generated on one of the systems in the many DIY measurement system photos shown below (and in the following post): DIY headphone measurement systems



While I think it's great that people are building rigs for measuring headphones, when it comes to trying to figure this out, I do not believe those systems are up to the standards of precision that should be expected when measuring the THD of a headphone like the Sennheiser HD800 for anything other than personal information or casual discussion.

Even if the FFT measurement by Tyll at Innerfidelity was wrong due to it being a DP modded HD800 instead of a stock HD800 it would not explain the clear differences in THD shown consistently. If you could do THD measurements of the HD800 and HD800S when you get back from CES that would be much appreciated.

 

[daltonlanny]

It would be nice if Tyll would weigh in and respond on this thread to get his opinion on this, and to defend himself and his measurements.
I have seen him respond before on this forum, so he is a Head-fi member.
Tyll, are u listening?

 

[Rob80b]

Somewhat related as we are only talking of tools to capture or recreate audio waveforms, which IMHO Sennheiser does quite well….I believe the biggest hurdle confronting this hobby is the fact that the ears and the drivers have little if any buffer in covering up irregularities in the transmission. Unlike listening to speakers, which transmit waveforms into a free and incongruous space, any deficiencies in the playback chain including the recording are painfully revealed.

Just happened to come across the paper written by John E. Johnson

https://hometheaterhifi.com/technic...e-quantization-error-dithering-noise-shaping/

https://hometheaterhifi.com/technical/technical-reviews/the-editors-equipment-list/

What caught my attention were the visual vulgarities in the reproduced sine waves just between 16 and 24bit.

Figure 6


You can see that each sine wave has four samples, with the positive and negative peaks at + 200 microvolts (µV) and – 200 µV respectively, but the waveform has characteristics of a square wave, which means there are numerous additional harmonic distortion peaks. There are some very low level sine waves mixed in with the 1 kHz wave. These are distortion peaks which are removed by dithering.


If we use 24 bits instead of 16, but keep the sampling frequency at 44.1 kHz, the square wave characteristics are gone (Figure 7, below).





These two examples may appear somewhat exaggerated but they indeed represent to a degree anomalies which can and do exist in many of our playback systems, especially when it comes to digital, and would account for some but not all reported discrepancies is sound reproduction among varies users.

And unless we all have very similar ears and playback systems, not to mention personal preferences and listening habits, there will always be opposing and contradictory opinions, but it’s always educational to hear both sides.

 

[JayKay47]

The only way to sort this out is to share the headphones that were measured with the owner of the other measurement system, and compare. Wait, didn't this happen with the Sony headphones that were under dispute recently, and one party did not post the results, cough cough.

 

[jude]

The only way to sort this out is to share the headphones that were measured with the owner of the other measurement system, and compare. Wait, didn't this happen with the Sony headphones that were under dispute recently, and one party did not post the results, cough cough.

You're right, I need to close that loop.

Tyll's got thick skin, as do I, but the energy around that discussion in our forums was getting combative and less collegial than I'm used to here at Head-Fi.

We even obtained another MDR-Z1R for the measurement set.

After Tyll posted on InnerFidelity...

...I continue to believe these headphones have too much energy in that area, but if you look at all the InnerFidelity measurements you can see a clear tendency for my head to show a peak in that area...and I think that's a measurement accuracy error.

...I admit I was in no rush to get back into it. You're right, though, it's true I owe you all the closing of this loop. I'm currently in Las Vegas for the Association of Loudspeaker Manufacturing & Acoustics (ALMA) annual conference, and then going to CES. When I get back, I'll post the follow-up Z1R measurements.

 

[TenMoonsNorth]

Well personally I'd be more inclined to trust Sennheiser and their engineers and their state of the art equipment as opposed to hobbyists with hand built measuring devices, which are really limited by environment when it comes to distortion measurements. When you look at distortion, look at the % of distortion we're talking about. To get really accurate readings, you need to be using an anechoic chamber and proper calibrated dummy-head. How many hobbyists have that equipment?

The stuff the hobbyists do on basic frequency response etc is admirable and pretty helpful. But taking the hobbyists THD and IMD readings as gospel over someone with far better set-ups is (IMO) just silly. Yes Sennheiser has a stake in this, but they have also proven over a number of years to be extremely competent in their design. I for one would trust their feedback on the situation until proven otherwise.

Sennheiser has said nothing publicly which is typical for Sennheiser. If Sennheiser believes it to be the same then they can show that.

Jude has only done FFT measurements as a comparison between the HD800 and HD800S.

Are you going to disregard the GRAS setup at Innerfidelity too just because it doesn't show what you want to see. This is my problem with your comment because there are differences shown in an FFT, that nobody else does, by one person on one setup and people are using that to wrongfully tell everyone to disregard any other setup just because it doesn't reach their desired conclusion. Then others are coming in here doing the same thing because they want to believe the HD800S is the exact same as the HD800 without the 6Khz resonance.

Well as it is at the moment the FFT measurements by Jude showed little difference between the HD800 and HD800S. That singular FFT done by Tyll at Innerfidelity may have been incorrectly labeled. The differences in THD at subbass frequencies for the HD800 and HD800S have been shown on the Innerfidelity GRAS setup and other DIY setups. It's an opportunity for inquiry and not hastily reaching conclusions.

https://www.innerfidelity.com/images/SennheiserHD800S.pdf

https://www.innerfidelity.com/images/MassdropHD6XX.pdf

Those correlate to this from the RTings GRAS setup.

 

[ubs28]

I think we need real proper facts and analysis to why certain measurements are superior.

Maybe most people on head-fi will just believe anything, but others need facts and evidence as why someone else his measurements are superior.

Best is to sit with Tyll and do some analysis of the strenght / weaknesses of both system and try to come to a joint conclusion. Maybe Tyll is wrong, maybe Jude is wrong. Or maybe both are wrong as both systems have too many weakenesses.

I personally don’t care who is right or wrong and I can swing both ways to either Jude, Tyll or even somebody else based on verifiable evidence (so no conversation with Sennheiser that we cannot verify).

But it is probably easiest to ask Alex Grell how he increased the bass like he himself said was accomplished with the HD 800 S.

 

[headr]

Both Tyll and Jude have been extremely transparent about the details of their measurement set ups. Jude's set up is clearly more advanced. I don't think even Tyll would argue with that. This is plainly seen given the repeated measurement artefacts that Tyll has to point out in his measurements that simply don't register on Jude's set up. Jude's set up is newer, more advanced, contains more components, and has much more infrastructure around isolating for external variables.

For all rational intents and purposes, where Jude and Tyll's measurements diverge, it makes most sense to consider Jude's measurements as more authoritative.

If you want to cling to Tyll's measurements, it's most likely because Jude's measurements are saying something YOU don't want to accept. There seems to be a lot of leaps of logic in the face of challenged assumptions here, because people put too much faith in certain people's measurements. This is what science is - it challenges assumptions, and leads the way. As Carl Sagan put it - science is a candle in the dark. Some of you are reacting how I would imagine flat earthers reacted to the idea of a round earth when evidence was presented.

We take the best information we have, and move forward. It really doesn't matter if you accept it or not.

And finally, and most importantly, why aren't people trusting their ears? If you don't know what a HRTF is, look it up. There is no one solution to headphones that will make everybody happy. We all have to make our own choices and if you prefer the HD 800 to the HD 800 S, or vice versa, no one will fault you for it.

More than anything this discussion is just proving that discounting either headphone for the purposes of "distortion" is not a valid reason - you need to focus on things like tonal balance. If you don't like one tonal balance over the other, so be it. Again, just don't pretend that is "distortion".

 

[headr]

Actually, even though I pretty much agree with you, "sounding different" is the very definition of 'distortion'. Every transducer distorts the signal in some way. Pretty much no way around it...

I would argue this is somewhat distorting (see what I did there?) the usage of what people generally mean when using "distortion" related to headphones and audio equipment. I would say audio distortion is generally taken to mean harmonic distortion, clipping, inter-modulation distortion, and so on. Basically, the first section here:

https://en.wikipedia.org/wiki/Distortion#Audio_distortion

When it comes to headphones, two headphones sounding different through a frequency response are simply a function of different tonal balance targets. One headphone might have elevated mids compared to another headphone, but we wouldn't put that under the "distorted" bucket either way - one headphone simply has a different tonal balance which some people might prefer and others might not. Again, especially regarding headphones, we have to consider things like the HRTF - which is a personal measure that varies by person to person. Because the HRTF will essentially mean there is no "perfect" frequency response, using words like "distorted" to actually mean "tonal balance" I believe is an inappropriate conflation of the word "distortion" with the above - ie. harmonic distortion, and other measure-able artefacts which are actually distorting the audio signal.

 

[Brooko]

Sennheiser has said nothing publicly which is typical for Sennheiser. If Sennheiser believes it to be the same then they can show that.

Jude has only done FFT measurements as a comparison between the HD800 and HD800S.

Are you going to disregard the GRAS setup at Innerfidelity too just because it doesn't show what you want to see. This is my problem with your comment because there are differences shown in an FFT, that nobody else does, by one person on one setup and people are using that to wrongfully tell everyone to disregard any other setup just because it doesn't reach their desired conclusion. Then others are coming in here doing the same thing because they want to believe the HD800S is the exact same as the HD800 without the 6Khz resonance.

Well as it is at the moment the FFT measurements by Jude showed little difference between the HD800 and HD800S. That singular FFT done by Tyll at Innerfidelity may have been incorrectly labeled. The differences in THD at subbass frequencies for the HD800 and HD800S have been shown on the Innerfidelity GRAS setup and other DIY setups. It's an opportunity for inquiry and not hastily reaching conclusions.

https://www.innerfidelity.com/images/SennheiserHD800S.pdf

https://www.innerfidelity.com/images/MassdropHD6XX.pdf

Those correlate to this from the RTings GRAS setup.

Please go back and read the post I was responding to. The guy was having a dig at both Sennheiser and Head-Fi about some sort of collusion, and trying to get a “conspiracy theory” thing going. If you read my post in context and not in isolation (as you have done), you’ll probably appreciate my intended meaning.

The funny thing is - while the debate is interesting, and ultimately I’d like to see where the differences are, I’ve never heard distorted bass on my own HD800S. It remains end game for me. No matter what the measurements say, they would not take away my enjoyment with this headphone.

And I’ve reached no conclusion - nor did my post state it (so please don’t put context where it wasn’t intended). I simply responded with my own feelings regarding accuracy of THD measurements which are extremely difficult to achieve without an anechoic chamber. How many hobbyists do you know who have one?

We know Tylls conclusion is different to Jude’s. Those measurements are worth exploring. But using other hobbyist set-ups as “proof” of Tylls is neither helpful nor conclusive. That is what I was responding to.

 

[ubs28]

Just because something is newer is not a logical answer why one system shows THD and an other doesn’t. What is the reason behind it?

I am not sure what makes you think I am not willing to side with Jude his measurements? If I see a real logical analysis which clearly proofs that this measurement is correct, then I will believe it without a problem.

And I already said that Tyll can also be wrong according to me as there are others such as Sennheiser who have far more expertise than these two.

 

[TenMoonsNorth]

Both Tyll and Jude have been extremely transparent about the details of their measurement set ups. Jude's set up is clearly more advanced. I don't think even Tyll would argue with that. This is plainly seen given the repeated measurement artefacts that Tyll has to point out in his measurements that simply don't register on Jude's set up. Jude's set up is newer, more advanced, contains more components, and has much more infrastructure around isolating for external variables.

For all rational intents and purposes, where Jude and Tyll's measurements diverge, it makes most sense to consider Jude's measurements as more authoritative.

If you want to cling to Tyll's measurements, it's most likely because Jude's measurements are saying something YOU don't want to accept. There seems to be a lot of leaps of logic in the face of challenged assumptions here, because people put too much faith in certain people's measurements. This is what science is - it challenges assumptions, and leads the way. As Carl Sagan put it - science is a candle in the dark. Some of you are reacting how I would imagine flat earthers reacted to the idea of a round earth when evidence was presented.

We take the best information we have, and move forward. It really doesn't matter if you accept it or not.

And finally, and most importantly, why aren't people trusting their ears? If you don't know what a HRTF is, look it up. There is no one solution to headphones that will make everybody happy. We all have to make our own choices and if you prefer the HD 800 to the HD 800 S, or vice versa, no one will fault you for it.

More than anything this discussion is just proving that discounting either headphone for the purposes of "distortion" is not a valid reason - you need to focus on things like tonal balance. If you don't like one tonal balance over the other, so be it. Again, just don't pretend that is "distortion".

You are acting exactly as I was talking about and your fallacious pleas to the most advanced show that you don't understand.

I hope this helps:

Well as it is at the moment the FFT measurements by Jude showed little difference between the HD800 and HD800S. That singular FFT done by Tyll at Innerfidelity may have been incorrectly labeled. The differences in THD at subbass frequencies for the HD800 and HD800S have been shown on the Innerfidelity GRAS setup and other DIY setups. It's an opportunity for inquiry and not hastily reaching conclusions.

For the people who don't know any better. There is no conflict at the moment between Jude's measurements and others as they measured different things. Nothing more can be said until they use the same method.

 

[devilboy]

OMG....

 

[james444]

Well as it is at the moment the FFT measurements by Jude showed little difference between the HD800 and HD800S. That singular FFT done by Tyll at Innerfidelity may have been incorrectly labeled. The differences in THD at subbass frequencies for the HD800 and HD800S have been shown on the Innerfidelity GRAS setup and other DIY setups. It's an opportunity for inquiry and not hastily reaching conclusions.

+1 on the bolded part.

Whether that singular FFT done at Innerfidelity has been incorrectly labeled, is obviously a question only one man can answer. So the best way to clarify that would probably be to contact Tyll directly.

Having said that, even though DIY rigs are naturally technically inferior to Head-Fi's $$$$$ rig, that doesn't really explain possible differences between the HD800 and HD800S measured on the same DIY rig. If these actually and repeatably exists and are not due to inadvertently picking a modded HD800 instead of a stock one for comparison, they'd warrant further investigation imo... regardless of whether the measurement rig in question is DIY or not.

 

[swspiers]

I would argue this is somewhat distorting (see what I did there?) the usage of what people generally mean when using "distortion" related to headphones and audio equipment. I would say audio distortion is generally taken to mean harmonic distortion, clipping, inter-modulation distortion, and so on. Basically, the first section here:

https://en.wikipedia.org/wiki/Distortion#Audio_distortion

When it comes to headphones, two headphones sounding different through a frequency response are simply a function of different tonal balance targets. One headphone might have elevated mids compared to another headphone, but we wouldn't put that under the "distorted" bucket either way - one headphone simply has a different tonal balance which some people might prefer and others might not. Again, especially regarding headphones, we have to consider things like the HRTF - which is a personal measure that varies by person to person. Because the HRTF will essentially mean there is no "perfect" frequency response, using words like "distorted" to actually mean "tonal balance" I believe is an inappropriate conflation of the word "distortion" with the above - ie. harmonic distortion, and other measure-able artefacts which are actually distorting the audio signal.

I hope this comes across as amicable, and with good spirit. Take a look at the title of this thread. I believe the word "impressions" is clearly visible.

Now, my definition of distortion is 100% accurate and applicable to virtually any system, measurement, sensory input, perception...etc. That definition, to be precise, is: anything that alters an object of attention from its original form.

Engineers have a certain perspective, or bias. Your bias is that 'distortion' should only be applied, in a headphone forum, to measurable physical distortions.

My studies and degrees are in Psychology. As such, my bias tends towards perception, interpretation, and meaning.

I think this is where most of circular arguments stem from on audio forums, and why they are so difficult to resolve. Engineers and behavioral-science types just plain think differently.

Now, I know you're entirely correct. 3 decades ago I studied electronics and dabbled in studio engineering, and I have forgotten virtually all of it. But when I read about 'distortion' on an audio forum, I am aware at all times of the different types of distortion that there are. And, when I'm in an impressions thread, I do not automatically assume harmonic or measurable artifacts.

I am not conflating anything, either. I just come from a different school of thought that may have a more accurate definition of 'distortion'.

(I hope you see that the last sentence is actually pretty funny, and totally tongue-in-cheek)