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Was anybody at the Sean Olive talk at CanJam?

deadkrillin

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Was anybody at the Sean Olive talk at CanJam & if so, do you have pictures of his slides?

A friend who attended said Sean revealed he's not using "Harman In-Room Flat" anymore & is using the same 5128 DF baseline as Crinacle & Headphones.com, which was suspicious and unexpected.

He said Sean also did small listening tests that showed that trained listeners tended to prefer Harman's new beta target, Harman IE 2019, SoundGuys' target, and Headphones.com's target roughly equally... which is also suspicious and unexpected. Hoping someone here has some pictures because I really don't know what to think.
 
Was anybody at the Sean Olive talk at CanJam & if so, do you have pictures of his slides?

A friend who attended said Sean revealed he's not using "Harman In-Room Flat" anymore & is using the same 5128 DF baseline as Crinacle & Headphones.com, which was suspicious and unexpected.

He said Sean also did small listening tests that showed that trained listeners tended to prefer Harman's new beta target, Harman IE 2019, SoundGuys' target, and Headphones.com's target roughly equally... which is also suspicious and unexpected. Hoping someone here has some pictures because I really don't know what to think.

No promises but if feasible some people who attended and recorded it are planning on making a video available on YouTube. Hope this will clear things out, and it's probably better to wait for the full version instead of just looking at a number of slides.
 
The target I like a lot and I think that it is not discussed enough is Ratings'.

I would like to read Sean's thoughts about what Rtings is doing with their measurements and target.
 
Just a few comments because I was not there.
5128 DF baseline
This is very unlikely to be an adequate target because DF is an unnatural and largely impossible acoustic condition. Olive made roughly the same comments in his papers about why the Harman headphone target became necessary.

He said Sean also did small listening tests that showed that trained listeners tended to prefer Harman's new beta target, Harman IE 2019, SoundGuys' target, and Headphones.com's target roughly equally... which is also suspicious and unexpected. Hoping someone here has some pictures because I really don't know what to think
Somewhat more probable, but in the end the targets are not dissimmilar from each other and there's not much that can be expected from headphones that have not been individually EQed using in-ear measurements. We know LF region will differ in tilt, curve and boost by a few dB, and on a person susceptible to leakage effects and preference. MF will be flattish on a fixture and on a person. HF will be elevated due to ear resonance but totally dependent on the dimensions of the ear and the final tuning based again on preference within a few dB.

Harman already did the baseline research about subjective preference and basic requirements (such as preventing high-Q resonances), and produced a defensible target. Beyond introducing a requirement for individual EQ and changes to source material standards for music presented through headphones, I don't know what other progress we can expect. Changing the shape of the curve by a few dB is not important. What would be much more valuable is if Harman produced recommendations about new headphone designs that show better FR stability across many people.
 
This is very unlikely to be an adequate target because DF is an unnatural and largely impossible acoustic condition. Olive made roughly the same comments in his papers about why the Harman headphone target became necessary.
I can ask if they're sure, but I think they were because they were also pretty shocked at this.

What would be much more valuable is if Harman produced recommendations about new headphone designs that show better FR stability across many people.
I actually agree that this would be way more interesting, as I mostly use over-ear headphones with EQ anyway.
 
Just a few comments because I was not there.

This is very unlikely to be an adequate target because DF is an unnatural and largely impossible acoustic condition. Olive made roughly the same comments in his papers about why the Harman headphone target became necessary.

Gunther Thiele would say that headphones are unnatural and a largely impossible acoustic condition to begin with :D - and argued in favour of using DF HRTF.

Just to be clear we're now talking here about using DF HRTF as a baseline, not as a target. On top of that DF HRTF baseline are added preference adjustments.

But conveniently, whether DF HRTF or another reference sound field such as Harman's "in room flat" is most appropriate is, in the case of the 5128, a bit of a moot point apparently, and generally speaking the targets that use the 5128 DF HRTF as a baseline + preference adjustments similar to the ones Harman added to their "in room flat" curve tend to produce, with the sort of coupling insensitive headphones Harman tested the original target with, up to a few kHz, quite similar error curves anyway.

Somewhat more probable, but in the end the targets are not dissimmilar from each other and there's not much that can be expected from headphones that have not been individually EQed using in-ear measurements. We know LF region will differ in tilt, curve and boost by a few dB, and on a person susceptible to leakage effects and preference. MF will be flattish on a fixture and on a person. HF will be elevated due to ear resonance but totally dependent on the dimensions of the ear and the final tuning based again on preference within a few dB.

Harman already did the baseline research about subjective preference and basic requirements (such as preventing high-Q resonances), and produced a defensible target. Beyond introducing a requirement for individual EQ and changes to source material standards for music presented through headphones, I don't know what other progress we can expect. Changing the shape of the curve by a few dB is not important. What would be much more valuable is if Harman produced recommendations about new headphone designs that show better FR stability across many people.

The test concerned IEMs. Indeed the most preferred curves are quite close to each others, possibly closer than previous studies Harman conducted, which could have contributed to a noisier result.

Harman IE 2019 is quite unsatisfying to me from a theoretical standpoint : it requires an explanation as to why individuals would want, on average, their bass and mids (and particularly the latter) to measure differently at their eardrum between in-ears and over-ears, and in a rather specific pattern. Some of the other targets discussed in that talk suffer less from that problem if not at all - but so much for the theory as Harman IE 2019 was at least as well liked as the alternatives proposed here.

I'm also increasingly skeptical that we can envision the idea of a target for passive IEMs (and most active ones as well) quite as we do for coupling insensitive over-ears (ie the ones with low inter-individual variation, good leakage resistance, and low positional variation), for reasons related to fundamental in situ response vs eardrum HRTF mismatch IEMs suffer from anyway (I'm thinking for a start about two variables at least here, ear canal length and eardrum / middle ear impedance variations), but that might be another discussion.
 
I'm also increasingly skeptical that we can envision the idea of a target for passive IEMs (and most active ones as well) quite as we do for coupling insensitive over-ears (ie the ones with low inter-individual variation, good leakage resistance, and low positional variation), for reasons related to fundamental in situ response vs eardrum HRTF mismatch IEMs suffer from anyway (I'm thinking for a start about two variables at least here, ear canal length and eardrum / middle ear impedance variations), but that might be another discussion.
Do over ear headphones somehow mitigate the effect of ear canal length and eardrum impedance variation, compared to IEMs?

If so, how?
 
You know, I've been following this subject of headphone targets for some time, and I don't understand the issue as well as many people here, and I don't care, because I equalize my (wireless, noise cancelling headphones) to my own target (what I like.) So I give my equalization a preference score which exceeds any passive headphone I am likely to encounter.

However, it makes me wonder what the most ideal equalization condition would be. If your headphones had a knob, allowing you to smoothly sweep from one tonal condition, to 'neutral' to a second condition, what would those curves be? I am always surprised how poorly thought out the equalization options are for products which include them.
 
The target I like a lot and I think that it is not discussed enough is Ratings'.

I would like to read Sean's thoughts about what Rtings is doing with their measurements and target.
Sean covered this a couple of years ago:

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As you see, they did not do well.
 
Was anybody at the Sean Olive talk at CanJam & if so, do you have pictures of his slides?

A friend who attended said Sean revealed he's not using "Harman In-Room Flat" anymore & is using the same 5128 DF baseline as Crinacle & Headphones.com, which was suspicious and unexpected.

He said Sean also did small listening tests that showed that trained listeners tended to prefer Harman's new beta target, Harman IE 2019, SoundGuys' target, and Headphones.com's target roughly equally... which is also suspicious and unexpected. Hoping someone here has some pictures because I really don't know what to think.
I was there and attended the talk. There will be a YouTube video of it soon. He showed listening results that the original 2019 Harnan target translated to the 5128 was rates the highest compard IE targets proposed by Headphones.com and the BK5128 DF.
 
I don't understand why Rtings doesn't use the Harman target. They're a wonderful website otherwise.
 
The target I like a lot and I think that it is not discussed enough is Ratings'.

I would like to read Sean's thoughts about what Rtings is doing with their measurements and target.
Has Rtings switched to a BK5128 test fixture? This talk was about targets for 5128
 
I don't understand why Rtings doesn't use the Harman target. They're a wonderful website otherwise.
My understanding is that the target is very much based on Harman but it's translate from GRAS 45 CA to Head Acoustics. So there will inevitably be some differences
 
Was anybody at the Sean Olive talk at CanJam & if so, do you have pictures of his slides?

A friend who attended said Sean revealed he's not using "Harman In-Room Flat" anymore & is using the same 5128 DF baseline as Crinacle & Headphones.com, which was suspicious and unexpected.

He said Sean also did small listening tests that showed that trained listeners tended to prefer Harman's new beta target, Harman IE 2019, SoundGuys' target, and Headphones.com's target roughly equally... which is also suspicious and unexpected. Hoping someone here has some pictures because I really don't know what to think.
The in-room flat curve I measured with 19 speakers in our Reference Room is identical to the 5128 DF.
 
Do over ear headphones somehow mitigate the effect of ear canal length and eardrum impedance variation, compared to IEMs?

If so, how?

Less mitigate, rather interact with it in a way that it closer to how uncoupled sound sources such as loudspeakers do.

For example, for ear canal length, when I saw this graph I felt a bit stupid and thought "huh why didn't I think of that before ?" :

Screenshot 2023-12-30 at 16.53.40.png

This is a simulation of the effect of three different ear canal lengths (first row) and girth (second) on the frequency response at the eardrum from that article : https://www.mdpi.com/2076-3417/8/6/918

If you plot the 22mm and 32mm traces over the 27mm one you get this, for the DT880 (over-ears) and AM12 (in-ears) :

Ear canal length sim.jpg


I had already printed a number of ear canal extensions of different lengths :

Screenshot 2024-01-21 at 17.14.02.png
Screenshot 2024-03-13 at 07.57.03.png


And compared how various IEMs and loudspeakers vary depending on ear canal length, with results trending similarly to the simulation above for passive IEMs (with some moderate differences depending on venting or damping, and active IEMs are a different story), and between loudspeakers and the DT880.

Then I got fascinated by Bose's CustomTune technology, measured them with different ear canal extension lengths, each time running a CustomTune calibration before measuring them, and found that they deliberately introduce more variation than what their passive design produces (you can't really measure them without their feedback system active, but I found a way) to align them better with how the DT880 or loudspeakers vary depending on that variable, so I think that to some degree they may have had a similar reasoning.

The TLDR would be that if the reasoning above is correct (and feel free to suggest otherwise !), a single target for an ear simulator with x canal length won't cause a problem for over-ears (particularly designs such as the DT 880, less so designs such as the K550) as if someone has a canal length of x+5mm, the headphones will naturally shift the resonance up and down more or less like what would happen with uncoupled sound sources such as loudspeakers, but for IEMs that may not apply, as they won't.
 
The in-room flat curve I measured with 19 speakers in our Reference Room is identical to the 5128 DF.
Shockingly, the sum of direct sound from many angles and reverberant sound with each direct sound source is very similar to the sum of sound from all possible angles :p
 
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