Headphones and the Harman target curve

[Robbo99999]

I'm not really sure why there is a debate as to what oratory's eq does to the treble on the hd600 or any frequency on any of his eq. Its writ large on the second from top graph on the right hand side of all his pdf. Now, how the cumulative impact of all the adjustments to a HP I suspect depends on the individual listener. The bigger debate is where one thinks treble starts.

Of course the 3 kHz is the region that gets corrected but isn't really what makes something sounding as treble-heavy but rather with extra presence (see BBC dip which is the same region) thats why I had called it upper mids above.

Well, that's right, whatever we choose to call it, we can can nonetheless all see what's happening to the EQ curve, which is the reality, so we can all see what the EQ is doing.

 

[Jose Hidalgo]

I said I didn't want to waste more time on this matter, and yet you keep bringing this back and drifting off-topic.
Now let me make this clear, both of you @preload and @thewas, as this will be my last post on this.

I think you got that backwards. Manufacturers need to stop being disrespectful to US, particularly with their claims about how their magical cables and interconnects have astonishing audible properties. Gag me now.

That is childish reasoning. How many times must we keep saying that cables and headphones are different things ? How many times must I repeat that a company may have been selling snake oil for decades (which is absolutely true about Audioquest), and THEN use a part of the huge amount of earned money to do actual R&D (the NHC has more innovative features that I've ever seen on a pair of cans) and create a pair of headphones that's all but snake oil? The team in charge of the NH/NHC/NO/NOC had nothing to do with cabling : they were hired to design headphones and they actually knew what they were doing. Because headphones are not cables.

I've said that already on ASR. I'm tired of repeating it. Maybe try and be a little more open-minded in order to understand something as simple as that.

On the contrary, the manufacturer is the one that has the burden of proving their claims. That is actually how science works. Make a hypothesis, design an experiment, report results, open it to criticism.

Yes, that's how science works. And Audioquest said this exactly, once again : " AudioQuest headphones do not boost high frequencies to create the false perception of greater detail. Instead, our headphones exhibit a much cleaner frequency response with much lower overall distortion, thereby delivering true detail matched by natural warmth, for a fatigue-free listening experience. " . Three distinct claims : frequencies, distortion and fatigue.

All these three claims have been demonstrated since then :

• There are many graphs that prove that their headphones don't boost high frequencies,
• There are graphs that prove that the overall distortion is really low, even on the low end,
• Not to mention the fatigue-free part, that's been more than proven already, as a consequence of recessed highs, low distortion and suspension system.

Hence the manufacturer claims have been fully proven. You can also read this page, in particular the "High-Frequency Emphasis & Edge Enhancement" part.

Are there any unproven claims about Audioquest on the cable side ? YES, lots of them ! I would never buy cables from them.
But are there any unproven claims about them on the headphone side ? I don't think so. Apples and oranges.

----------

Funnily few posts and hours ago you also called that 3 kHz also as upper mid peak and that is doesn't annoy you so you don't feel the need to correct it

I can't believe that I have to say this again. So for the last time too :

• The UPPER MID "out-of-the-box" HD600 boost (let's say about 1K-2K) doesn't bother me. It's subtle like shown on the FR and gives presence to the voices and instruments IMHO.
• The TREBLE "out-of-the-box" HD600 boost bothers me a little. It's above the target response and can be attenuated by EQ. BTW, it's above the target response in the 3-4 KHz region AND ALSO in the 6.5-9 KHz region, which is where sibilances happen according to your own link. I guess this explains what my ears have been telling me : no clear sibilances but almost, like I already said.

By the way, sibilance is also not there but where the main treble is, so above 5 kHz https://www.gearslutz.com/board/rap...n/469876-what-frequency-sibilance-around.html

By the way, there's no official, worldwide, commonly-accepted definition of where exactly every sound register begins and ends. Here are 3 definitions among others :

Even on the headphones.com graph that I just posted, the treble range is said to cover 2 KHz to 20 KHz. And when I said "treble" repeatealy in my past posts, I didn't specify a frequency range. I just said "treble", which basically meant "above 2 KHz". I hope I won't have to repeat this.

You seem to have made a personal mission to annoy me on this thread, by trying to prove me wrong. Unfortunately you haven't succeeded, simply because all my posts are consistent. I'm not going to discuss this any further (read this again if needed, it may prevent you from posting and not receiving any reply). And honestly, if any of you keeps annoying me, I'll just block him to avoid further drama.

Good day.

 

[thewas]

BTW, it's above the target response in the 3-4 KHz region AND ALSO in the 6.5-9 KHz region, which is where sibilances happen according to your own link.

The Oratory measurement on which we were discussing and which is based on the Harman curve (Rtings use their own one which is slightly different) doesn't show such at the 6-9 kHz sibilance region. If you hear such that is absolutely fine and acceptable though as it can be also as said due to different individual HRTF and perception, here we can only discuss though on objective data.

By the way, there's no official, worldwide, commonly-accepted definition of where exactly every sound register begins and ends. Here are 3 definitions among others :

I agree that there is not one common definition, anyway now we know what each is talking about.

You seem to have made a personal mission to annoy me on this thread, by trying to prove me wrong. Unfortunately you haven't succeeded, simply because all my posts are consistent. I'm not going to discuss this any further (read this again if needed, it may prevent you from posting and not receiving any reply). And honestly, if any of you keeps annoying me, I'll just block him to avoid further drama.

The one who gets personal here and spreads poison is you. Also we had proved you at least time 3 times wrong in this thread, which two of you thankfully accepted. By the way the tactic to tell others not to reply on your replies is not nice, its a open forum, if you don't like the discussion just don't participate in it.

 

[Feelas]

Actually, it is not entirely true that spectral effects that are bypassed by headphone listening should be equalized: room gain, reflection/diffraction against head and torso, and absorption of clothing and hair (as applicable).

It's been discussed before, that the angle of incidence towards ear affects what exact pinna interaction is going on. Also, the whole marketing towards "omitting the ear-canals in design" is - I think - partly incorrect, since I guess for some time the headphones aren't designed based on blocked ear-canal response. Most of the arguments are correct, yet the premise is incomplete and no more valid today, since the procedure calls for measurement w/ some ear-canal resonance happening (despite that, it can be measured out).

Also, using the "There is little certainty to be found in any headphone measurements above 8kHz." is agreed to be true, yet has more place in a thesis or an essay, here it is used to appeal to subjectivists in a manipulative way.

Low THD is a fact, yet actually omitting that distortion-perception is frequency dependent (thus presenting on a 2% scale is a creative use of statistics on it's own) also isn't nice. That doesn't make me trust AudioQuest, when looked at in a critical way. The low THD and a very customized tuning showcase the technical knowledge of the people included, yet that doesn't make the whole article unbiased. And anyways, bio-cellulose drivers aren't actually something new, for a long, long time they're not, even in headphones.

And actually the "Sharpness" analogy is nonsense, simply because the mechanism behind is much more different. Being "fatigue-free" throws the idea of many recordings straight through the window.

The whole article uses scientific arguments to kill a big straw-man set up by AudioQuest, finished up with mentioning gear ranging from USB cables to AudioQuest Q-Feet.

 

[preload]

I said I didn't want to waste more time on this matter, and yet you keep bringing this back and drifting off-topic.
Now let me make this clear, both of you @preload and @thewas, as this will be my last post on this.

That is childish reasoning.

Irony: "This will be my last post on this" can generally be considered a childish response.

How many times must we keep saying that cables and headphones are different things ? How many times must I repeat that a company may have been selling snake oil for decades (which is absolutely true about Audioquest), and THEN use a part of the huge amount of earned money to do actual R&D (the NHC has more innovative features that I've ever seen on a pair of cans) and create a pair of headphones that's all but snake oil?

I'm glad we agree that manufacturers have been selling "snake oil" products for decades. It's also certainly possible they can reinvest these dishonestly-earned profits into actual R&D. However, that's a different point from the one you made earlier, which was that we must trust manufacturer claims and that if we don't agree, it's up to US to disprove them with scientific evidence.

I completely disagree that we should blindly accept the product claims of any manufacturer, particularly those that have compromised their own credibility by making speaker cable claims. But if it makes you feel better to do so, c'est la vie.

 

[preload]

Okay Amir, which headphone is the red-circle? I know you know!!!!
My guess is AKG K712. It could also be the Senn HD650, but there's no way that could be most preferred.
View attachment 98108

It looks like the #2 preferred HP was the Sony MDR-7506.

Out of curiosity, I purchased and tried out a pair of MDR-7506 headphones, which supposedly had a FR curve that ranked #2 when played back on the standard headphones used in the study. And I have to say that they sound absolutely horrible. As in unlistenable. As in clearly, something was very off about this Harman experiment. And to be quite honest, it now makes me a little suspect about other Harman publications. The headphones are THAT BAD.

 

[Feelas]

Out of curiosity, I purchased and tried out a pair of MDR-7506 headphones, which supposedly had a FR curve that ranked #2 when played back on the standard headphones used in the study. And I have to say that they sound absolutely horrible. As in unlistenable. As in clearly, something was very off about this Harman experiment. And to be quite honest, it now makes me a little suspect about other Harman publications. The headphones are THAT BAD.

They seem to be like Harman w/ slight v-tilt (+-3dB from curve on the whole length), so if you don't like Harman, these won't work for sure. How much time did you give them? Are they as uncomfortable as can be read in numerous places? K712 could be straightening out the terrible shallow earpads (I read these are a problem) influence.

On the other hand, crossing out a decade (or more) of various headphone experiments, which might actually push us forward towards anything much better, is, well... a bit over the top.

 

[preload]

They seem to be like Harman w/ slight v-tilt (+-3dB from curve on the whole length), so if you don't like Harman, these won't work for sure. How much time did you give them? Are they as uncomfortable as can be read in numerous places? K712 could be straightening out the terrible shallow earpads (I read these are a problem) influence.

On the other hand, crossing out a decade (or more) of various headphone experiments, which might actually push us forward towards anything much better, is, well... a bit over the top.

Well, good point. Let's look at what the evidence is for OE/AE headphones, from the Harman paper.
1. The agreement in listener preferences between actual headphones and virtual headphones EQ'd to "simulate" the actual headphone only had an r of 0.85, using measurements on their GRAS 45. This gives an R^2 of 72%. Not a great correlation between the experimental condition (virtual headphone) and real life, if you ask me.
2. Even then, Harman's predictive model that mathematically evaluated deviation from the Harman Target Curve (for headphones) only correlated 74% with those virtual listener preferences (which, in turn, only correlate 72% with real life).
3. Harman's own research shows that there are definite, and significant differences in the quantity of treble and bass (read: EQ curve preferences) preferred based on gender, age, and country of residence!

Which means that for some reason, however we're measuring FR for headphones does not seem to have the same predictive value as when we do it for loudspeakers. And something about the way the headphones present the sound in 3-dimensions to the ear is important and perhaps not yet understood yet. Whereas loudspeakers present a mix of direct and slightly delayed reflected sound and interact with a listener's body, headphones present just that direct sound, perhaps with some internal resonances. Dunno. But my observation that the MDR-7506 sounds like I'm listening inside a toilet bowl is not necessarily inconsistent with Harman's research.

 

[Feelas]

Which means that for some reason, however we're measuring FR for headphones does not seem to have the same predictive value as when we do it for loudspeakers. And something about the way the headphones present the sound in 3-dimensions to the ear is important and perhaps not yet understood yet. Whereas loudspeakers present a mix of direct and slightly delayed reflected sound and interact with a listener's body, headphones present just that direct sound, perhaps with some internal resonances. Dunno. But my observation that the MDR-7506 sounds like I'm listening inside a toilet bowl is not necessarily inconsistent with Harman's research.

Yes, exactly, not at all inconsistent, since only the FR was considered in their study, since it seems to be the most important component for most buyers. The spatial & imaging matters were thrown out with the water and disregarded here. Perceived width & spatial matters seem to coincide with pad depth, you'd probably be able to see (and yet I doubt you'll dump another dime on MDRs), having the pads changed to something deeper - I guess HM5 pads are known to fit 7506? Going by the very funny descriptor - what exactly do you consider the toilet bowl - perceived lack of width or merely the FR characteristic?

 

[preload]

An interesting experiment would be to take a pair of Revel Salon2's (for example), put them in an ideal room, then take 30 different people, stick calibrated mics into their ear canals, and measure the resultant FR curve. We know it isn't flat. But the question is, how much variation will there be in the measured curves, and where will that variation occur? My guess is that there will be quite a bit of variation around an "average" curve.

Perhaps this study has already been done and published. I imagine that it has. Does anyone know?

 

[Feelas]

An interesting experiment would be to take a pair of Revel Salon2's (for example), put them in an ideal room, then take 30 different people, stick calibrated mics into their ear canals, and measure the resultant FR curve. We know it isn't flat. But the question is, how much variation will there be in the measured curves, and where will that variation occur? My guess is that there will be quite a bit of variation around an "average" curve.

Perhaps this study has already been done and published. I imagine that it has. Does anyone know?

Not with Revels, but Dreyfus had made a beautiful contribution here regarding the "classical" studies about freq variation between subjects, similar differences should perhaps show up.

Beside that, ear canal resonance is heck important and you don't really take that into account w/ sealed canal measurements and cannot account for it (not without EQ) when designing headphones. This is the dreaded 3k-8k (afair the variance can be really high) range which makes or breaks mostly anything for anyone.

 

[pkane]

I think we should be able to run our own study to determine the most preferred curve for any particular headphone.

As long as enough people participate, everyone can report their favorite EQ settings for that headphone. Everyone can compare any two correction curves and report using some standard relative ratings and scale (better/worse in bass, mids, treble, imaging, detail, etc.) Anyone can pick any of the EQ settings they like and tweak it to sound better, and then share these with the group. We might be able to converge on a single curve that works for most... or not. But it'll be fun to see what others like and what they are listening to. Will only work if there's enough people participating and only with headphones that are fairly well represented here, like HD650

 

[kkeretic]

As long as enough people participate, everyone can report their favorite EQ settings for that headphone.

If someone is interested, I can share my parametric EQ settings for my current set of headphones (AKG K712, Sundara, HD599 and ATH-M50x) for MathAudio Headphone EQ, FabFilter Pro-Q 3 and Equalizer APO. All made using AutoEQ (harman_over-ear_2018_wo_bass compenstation curve), based on the FR graphs from oratory1990.

 

[pkane]

If someone is interested, I can share my parametric EQ settings for my current set of headphones (AKG K712, Sundara, HD599 and ATH-M50x) for MathAudio Headphone EQ, FabFilter Pro-Q 3 and Equalizer APO. All made using AutoEQ (harman_over-ear_2018_wo_bass compenstation curve), based on the FR graphs from oratory1990.

Let's start a new thread for headphone EQ settings. There's already one for speaker/room EQ, but none for headphones, as far as I can tell.

 

[Music1969]

I believe it is the AKG NC700NC. It costs $340.

This wasn't on the list?

Do we now know which headphone that was?

@preload

Not on the list of headphones in the study though. Im eyeballing the red circle as more $200 than $340 too

 

[bobbooo]

This wasn't on the list?

Do we now know which headphone that was?

@preload



View attachment 108074

That's just the AKG K712 equalized to the Harman target i.e. the 'high anchor' of the study (hence the rating of 100).

 

[Music1969]

That's just the AKG K712 equalized to the Harman target i.e. the 'high anchor' of the study (hence the rating of 100).

Thanks! Amir mentioned he thought it was AKG NC700NC

 

[bobbooo]

Thanks! Amir mentioned he thought it was AKG NC700NC

Nope, it's the Harman target as the high anchor. As stated in the paper:

Listeners rated 8 headphones in each trial that included high (the new Harman AE/OE target curve) and low anchors. On average, both trained and untrained listeners preferred the high anchor to 31 other choices.

As has already been said, the AKG N700NC wasn't even included in the study.

 

[Aerith Gainsborough]

“Less Bass Is Better”: This group, 21% of listeners, prefers 2 to 3dB less bass than the Harman curve and 1dB more output above 1kHz. This group is disproportionately female and older than 50.

Sounds like me.
Initially I tried Oratory's EQ on my DT-880 and the bass was just obscene, drowning out everything else.
Lowered it to a +4dB boost and kept the corrections in the high end to tame the Mt. Beyer a bit. So far, it sounds good to me.

 

[Sean Olive]

I've done something slightly different: measure actual frequency response using in-ear microphones, and then adjust to a straight, tilted line target with HD-650. Sounds better to my ears than the Harman target, as described here.

After correction, here's the result is (this is predicted result hugging the straight blue target line, not measured, measured was very close):
View attachment 96228


If you want to try my corrections:
(the +10dB shelf filter at around 30Hz is probably something you might want to reduce, depending on your ears and amplifier, also the 13.8k peaking filter is probably not needed, but was added by REW and I adjusted it slightly).

View attachment 96230

Let me know how this sounds to you, if you try it. These were derived for my own ears, so who knows how they'll sound to anyone else

I'm confused. Maybe you can clarify this.

You said this measurement was based on microphones in your ears. Are the microphones at the entrance of the ear canal (ie blocked meatus) or probe mics at your ear drums (DRP or ear drum reference point)

If they are blocked meatus measurements which they appear to be then you are not including the 3 kHz ear canal resonance.

The Harman Target Curve is measured at the end of the ear canal and includes the 3 khz resonance. So have you accounted for that when equalizing to the Harman Target? If you are equalizing a blocked meatus measurement to a curve based on a DRP that would explain why it sounds bad. Just checking.