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Audio Theory, Setup, and Chat

rnrgagne's Avatar rnrgagne
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Quote:
Originally Posted by craig john View Post

Sanjay, do you think a monophonic test is a valid way to compare RC products? (See Slide 12 in the linked document.)
Also, does anyone know, if the Audyssey Sound Equalizer doesn't find more than one speaker, will it even continue?

I was thinking the same thing, while I understand how it would be easier to hear a signal difference from a single point source, I can't get my head around how that test could be a valid to see if an EQ designed for multi-seat multi-channel application is doing what it's designed to.

I'm pretty sure Audyssey is an averaging algorythm and each channel likely has a set number of filters, if it's only doing 2 channels that would seem to me to be limiting it's averaging potential.
sdurani's Avatar sdurani
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post #902 of 3048
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Quote:
Originally Posted by Bigus View Post

Since the room was almost certainly used in tuning harmon's algorithm, you can rest assured there were no such quirks for their system. Hence, I'm not surprised their own solution performed well in their own room.
In what type of room do you believe smoother & perceptually-flat response wouldn't be preferred over less smooth & measured-flat response?
arnyk's Avatar arnyk
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Quote:
Originally Posted by craig john View Post

Sanjay, do you think a monophonic test is a valid way to compare RC products? (See Slide 12 in the linked document.)

There's a larger question, and that whether monophonic testing is a valid way or even informative way to do SQ testing?

For the record, I believe that every ABX test that I've done or heard of was done in stereo.

I find mono in a listening room context just too strange to really engage with.

Context does matter, and if you can't relate to a test it is IME very hard to evaluate SQ.

At this point RC products can be relatively easily compared by setting up the comparison as a comparison between two receivers, one running a RC product, and the other running a different RC product or no RC at all. For extra credit run the same product on two receivers and see if there is a difference in preference! ;-)

It should be pointed out that subjective preferences are not necessarily transitive. IOW if you like A better than B, and B better to C you have no global guarantee that you will like A better than C. Serious experimenters either do the necessary work to establish transitivity, or just compare all of the interesting permutations.

The apparently unsupported implication that RC preferences are transitive becomes another potentially serious flaw in any conclusions that might be based on the 2009 Harman test since as I read it, the hidden reference was always flat response. So, the fact that RC methodology 1 was highly preferred over RC methodology 4 does not mean that RC methodology 1 was necessarily preferred over RC methodology 2, for example.
wse's Avatar wse
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OK the best would be the king of the hill in terms of EQ

http://www.datasatdigital.com/consumer/products/rs20i.php

Off course unless the room is designed by an acoustical engineer then it is a waist of money smile.gif

http://www.laphil.com/philpedia/about-walt-disney-concert-hall
arnyk's Avatar arnyk
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Quote:
Originally Posted by wse View Post

OK the best would be the king of the hill in terms of EQ
http://www.datasatdigital.com/consumer/products/rs20i.php

A superficial scan of the home page contains the following potential red flag:

"stackable multiple EQs"

If you use modern equalization techniques based on impulse responses and convolution, there should be never be any need for more than one layer of equalization.
craig john's Avatar craig john
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Quote:
Originally Posted by sdurani View Post

In what type of room do you believe smoother & perceptually-flat response wouldn't be preferred over less smooth & measured-flat response?
You make it seem as if Audyssey doesn't provide smoother and perceptually flat response. It does in *my* room:





Downward sloping curve and all.

In addition, Audyssey reduces modal ringing significantly:

Audyssey Off:


Audyssey On:


Craig
sdurani's Avatar sdurani
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Quote:
Originally Posted by craig john View Post

Sanjay, do you think a monophonic test is a valid way to compare RC products?
ONLY if you can demonstrate that it doesn't result in a significant difference in preference, which Harman has done in previous research papers.

"All of the fidelity ratings used here came from monophonic listening tests. Over half of the loudspeakers were evaluated in stereophonic comparisons as well, but these data are not included. As pointed out previously [1], highly rated loudspeakers receive closely similar ratings in both stereo and mono tests, but loudspeakers with lower ratings tend to receive elevated ratings in stereo assessments. This scaling distortion, combined with the increased judgment variability in stereo tests, encouraged the use of the monophonic test results.

"So far the discussions have concentrated on sound quality as assessed in monophonic listening tests. As pointed out earlier, listening in stereo has not been found to change the fidelity ratings of the high-ranking loudspeakers; however, there is the matter of spatial reproduction that must be addressed.

"In [1] a good correlation was shown between the fidelity ratings and an overall spatial quality rating. This suggests that much or most of what is perceived to be a good reproduction of auditory images and spaciousness is due simply to accurate sound reproduction. A good monophonic loudspeaker used in pairs is, it seems, a good stereophonic loudspeaker."
Quote:
Originally Posted by craig john View Post

In fact, there is a multi-page Guide that's been written and published on this forum to help user's get it right.
At the time Audyssey was selling their Sound Equalizer, did they include this multi-page Guide?
arnyk's Avatar arnyk
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Quote:
Originally Posted by sdurani View Post

ONLY if you can demonstrate that it doesn't result in a significant difference in preference, which Harman has done in previous research papers.
"All of the fidelity ratings used here came from monophonic listening tests. Over half of the loudspeakers were evaluated in stereophonic comparisons as well, but these data are not included. As pointed out previously [1], highly rated loudspeakers receive closely similar ratings in both stereo and mono tests, but loudspeakers with lower ratings tend to receive elevated ratings in stereo assessments. This scaling distortion, combined with the increased judgment variability in stereo tests, encouraged the use of the monophonic test results.
"So far the discussions have concentrated on sound quality as assessed in monophonic listening tests. As pointed out earlier, listening in stereo has not been found to change the fidelity ratings of the high-ranking loudspeakers; however, there is the matter of spatial reproduction that must be addressed.
So you're saying you can't see the holes in the logic, above?
craig john's Avatar craig john
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Quote:
Originally Posted by sdurani View Post

ONLY if you can demonstrate that it doesn't result in a significant difference in preference, which Harman has done in previous research papers.
Yeah, I know, they quoted their own research. While that's nice, it has about as much credibility as them testing another manufacture's product and finding their own product to be better. rolleyes.gif

IMO, this test is worthless because it is a monophonic test of a product that is clearly intended to be used in a multichannel system. It was also done by "trained" listeners, "trained" by Harman. eek.gif Of course, they're going to prefer the Harman sound.
Quote:
Originally Posted by sdurani View Post

At the time Audyssey was selling their Sound Equalizer, did they include this multi-page Guide?
Obviously, not. It's not Audyssey's intellectual property. It's been a work in progress on the Audyssey thread for some time. It was started because there are so many potential ways that a calibration can be screwed up. I'm sure Harman found at least one of those ways.

The measurements I posted above are not the raw post-Audyssey results. I changed all the crossovers, and I adjusted the subwoofer distance. In addition, I overrode the level-matching process and applied gain-matching to the subs. If Harman did none of those things, it's not surprising it wasn't preferred. Here is a raw Audyssey result with the Audyssey applied distance setting in blue and the corrected distance in green:



Craig
Chu Gai's Avatar Chu Gai
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I for one would have liked to have seen the extent of variability using two speakers and their room correction. Would it be reasonable to assume that adding a center channel and then later two rear speakers would further increase the variability?
amirm's Avatar amirm
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Quote:
Originally Posted by craig john View Post

Yeah, I know, they quoted their own research. While that's nice, it has about as much credibility as them testing another manufacture's product and finding their own product to be better. rolleyes.gif
I think not. AES Paper title: "Subjective Measurements of Loudspeakers: A Comparison of Stereo and Mono Listening"
Author: Toole, Floyd E.
Affiliation: National Research Council, Ottawa, Ontario, Canada
AES Convention:74 (October 1983)

"Earlier papers have described monophonic comparisons of loudspeakers in controlled listening tests that produce sound quality assessments with considerable consistency and order. Repeating the experiments in stereo, using a positional substitution technique, produced sound quality ratings with similarities and differences. For example, the ranking is similar, with highly-rated products retaining their high scores, however listeners were more forgiving of products with low scores from the monophonic tests. The relationship to measured performance is considered."

People forget that almost all the research we attribute to Harman in this area, came about when they hired Dr. Toole from NRC and he brought people like Sean Olive and what they knew with them. Their arrival at Harman caused fair amount of grief with just as many naysayers as there are in this thread. But test after test proved what they were advocating and the culture changed. So no, this is not Harman. The research was done as part of Candian government funded research unattached to any company let alone an American company called Harman. The research was extended while at Harman to go beyond stereo but the results simply confirm what was already known.
Quote:
IMO, this test is worthless because it is a monophonic test of a product that is clearly intended to be used in a multichannel system.
There is no evidence that if you screw up one channel, you get to make up for that by screwing up the rest smile.gif. And research has been done to quantify applicability:

"Comparison of Loudspeaker-Room Equalization Preference for Multichannel,Stereo, and Mono Reproductions: Are Listeners More Discriminating in Mono?"
Sean E. Olive1, John Jackson2, Allan Devantier3, David Hunt4 and Sean M. Hess5
Harman International, Northridge, CA, 91329, USA

Digital loudspeaker-room correction products are more popular than ever, despite the general lack of perceptual
studies on their performance over a wide range of different playback conditions. This paper describes the first of
several experiments that explore the influence of important acoustical and perceptual factors on their performance.
In this experiment, a panel of trained listeners gave comparative preference ratings for three different loudspeaker
equalizations based on anechoic and in situ measurements evaluated in a semi-reflective room, using three
multichannel music recordings reproduced in surround, stereo, and mono. These equalizations were compared to the
unequalized loudspeaker. The results are summarized as follows: all three equalizations were equally preferred over
the unequalized system. The differences in preference ratings increased as the number of playback channels was
reduced from 5 channels (surround) to 1 (mono).
"

Quote:
It was also done by "trained" listeners, "trained" by Harman. eek.gif Of course, they're going to prefer the Harman sound.
That is a misconception that I used to have too and then I took the test and voted just like them! Of course, I could have just read the research and saved myself some embarrasment:
http://seanolive.blogspot.com/2008/12/loudspeaker-preferences-of-trained.html

"Do Untrained Listeners Prefer the Same Loudspeakers as Trained Listeners?"

I will save you reading the whole report by giving you the punchline:

TrainedvsUntrained.jpg

The gray vertical bar is the Harman Trained listeners. While they are a heck of a lot more critical of flaws in reproduction systems, they vote like ordinary humans when it comes to ranking devices. The green speaker (M) got worst rating by them and every other group that tested them. Likewise the red is the best regardless of who tested it. I say this within the margin of error.

In the test we are discussing, if my memory is right, only two of the six were expert listeners. The rest were not. The experts did manage to discriminate between systems better. But per my earlier graph, the rankings for the systems was consistent across listeners:

i-HL937s9-XL.png

As I noted, I have sat through such blind tests at Harman and not once but twice. My votes in one case matched them 1:1 for every test, and the other, all but one test matched. And the one that didn't was a toss up (score of 7 vs 6 out of 1 to 10). So no, there is no "Haman sound." It is the sound we hear when we remove bias. We share a lot of likes and dislikes with our fellow humans, as much as we like to think we are different.

Last but not least, note how careful they are in testing these assumptions. There is nothing they take for granted. We really have a gift in audio science here in how they do so much research and bring so much objectivity to sound reproduction. And at the end, they give it all away for everyone to learn and use.
Randy Bessinger's Avatar Randy Bessinger
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I would like to add at least one item before going on to something else. America, Canada and Harman are not the only companies and countries doing audio research. Dr. Toole and Dr. Olive have done great work and advanced the science but I think there are a few others doing some good work as well.
craig john's Avatar craig john
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Quote:
Originally Posted by amirm View Post

I think not.

amirm, you can drink, (and regurgitate), the Harman Koolaid all you want. For me, a "test" that compares multichannel systems using one channel, where the single speaker appears to be misplaced in a corner as opposed to directly in front of the listener, that uses listeners trained by the tester, and where the tester likely "tweaked" their own system, but didn't tweak the competitors system... a "test" like THAT has zero credibility... for me.

I'll take my own measurements of an Audyssey-based system, tweaked by me, rather than some bogus test that is set up to get the desired results.

BTW, if you need some help learning how to integrate Audyssey into a high end system, let me know.

See ya...

Craig
Chu Gai's Avatar Chu Gai
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Craig, regardless of your critique of Harmon's work, isn't their conclusion of the desirability of achieving a flat frquency repsonse essentially the same as what you've done? If not can you point out where you differ significantly?
sdurani's Avatar sdurani
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Quote:
Originally Posted by arnyk View Post

As slide 8 shows, the primary task at hand was to address small lower midrange peak and a more serious upper midrange dip that appears to be characteristic of the B&W 802N speaker.
That wasn't the "primary task", instead it was to find out what subjective factors were most preferred and what objective measurements correlated with those preferences, hence the title of the paper. It's the same thing they always do, compare subjective preference with objective measurements, as can be seen in their previous papers on loudspeaker preference.
Quote:
Originally Posted by arnyk View Post

There were also some bass issues, but surprisingly enough the two subwoofers in use were not deployed in accordance with the best available wisdom for deploying 2 subwoofers, as promulgated by Harman themselves.
That's because they used only one subwoofer (and one speaker) for the comparison.
Quote:
Originally Posted by arnyk View Post

Finally, we know for sure that the Audessey product used was the Audyssey Room Equalizer, which is obsolete according to some, for sure not the same as Audessey's best current consumer products, and not even for sale as a new product according to others.
"Finally"? The fact that they were using Audyssey's stand-alone box, which wasn't "obsolete" at the time of the comparison, was hidden in plain sight since the day the paper was published.
Quote:
Originally Posted by arnyk View Post

The relevance of the absence of volume compensation depends on the actual reference SPL that Harman used when they ran their tests.
Test subjects listened at a level that was comfortable to them, which is what consumers do at home. A company designing room correction is only fooling itself if they limit the blind testing to reference level and/or rely on an optional feature (loudness compensation), because in the real world neither of those variables is guaranteed.
Quote:
Originally Posted by arnyk View Post

There are so many other points of ambiguity and contention that the Harman tests remain meaningless, except that they are what they are - one data point in a universe that contains many relevant points that need to be known, but are as yet unknown.
The reason that Olive's comparison remains meaningful is because there has yet to be a similar comparison refuting the findings.
sdurani's Avatar sdurani
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Quote:
Originally Posted by rnrgagne View Post

So they pasted various RC logos on a dart board to make a decision on which to use?
"Various logos"? When Denon first introduced room correction in their receivers, who besides Audyssey was licensing that sort of technology to receiver manufacturers?
sdurani's Avatar sdurani
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Quote:
Originally Posted by Randy Bessinger View Post

Efficienc does not go down (or is much improved from the original Welti method) with Soundfield Management according to Toole.
Probably improved from the original Welti paper, maybe because they disabled level adjustment as one of the parameters of SFM (at least in the Synthesis version of ARCOS). They felt that the small improvement in consistency wasn't worth the loss in bass. Same reason why they usually recommend placing four subs in four corners rather than the midpoints of the four walls, even though the latter yields an improvement in consistency. The level boost (and, therefore, better heardroom) that came with corner loading wasn't worth giving up to get slightly better consistency. Apparently they aren't sticklers when it comes to recommended practices, choosing practicality over sticking firmly to even their own research.
Quote:
Originally Posted by Randy Bessinger View Post

I could care less so don't include me in that.
You're quoting a reply I made to Arny, so I wasn't including you "in that". Besides, why have you been misreading my comments lately as some sort of personal attack on you. Seems you did this in another recent thread.
Quote:
Originally Posted by Randy Bessinger View Post

I am however interested in how valid certain tests are and how much is more marketing than scientific.
I'd be as interested as you (regarding marketing vs research) if Harman's room correction was going to compete in Audyssey's market space or price range. As far as I know, Harman doesn't plan on licensing their room correction, like Audyssey does, and the cost of Harman's room correction (just the room correction, loaded in SDEC units) is more than the most expensive pre-pro with Audyssey. If they are marketing, then it's not against Audyssey.
Quote:
Originally Posted by Randy Bessinger View Post

The "cheaper" solution that Roger Dressler uses in his room and I have used in mine was all that was available at close to a reasonable amount and even it was hard to find. I called Harman's 800 number one day and was told they never heard of it...amazing.
You wouldn't believe how hard I had to look to find one. It's like the company doesn't want to acknowledge it exists, let alone make money from selling it. Amazing indeed.
Bigus's Avatar Bigus
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Quote:
Originally Posted by sdurani 
In what type of room do you believe smoother & perceptually-flat response wouldn't be preferred over less smooth & measured-flat response?
Why are you asking me this question? It seems again you have missed my point, and not by a little. Perhaps including the sentence before and after the snippet you quoted would have provided a bit more context. As a refocusing of your question, do you believe one room might prove difficult for one smoothing algorithm, whether due to some combination of measured location variances or otherwise, and not for another? One algorithm chooses to include a suspect measurement, another excludes it, with obvious differences in generated filters? I don't know that such rooms exist for certain as I haven't done exhaustive research on it. But it seems plausible. For the record, I highly doubt the Harman room gave the audyssey product. I can guarantee however that it didn't give the Harman product problems of this type. So again, I'm not surprised it performed well in a room it was tested/developed in. I should be surprised audyssey performed so bad, but there is a logical enough explanation for that. Repeated testing would be more useful to me because right now we can only speculate.

Which brings me back to the missed point... lots of people are speculating about things the data simply doesn't support or can't support. Claims that no eq is better than audyssey are overgeneralized and speculative based on limited testing using products potentially irrelevant to the current marketplace. This claim was made for a specific reason, to support a specific agenda, with this specific data cited as the proof. Fraid not.

And again for the beancounters, I have never owned an audyssey product and would probably love the Harman solution if I could afford it at the moment.
markus767's Avatar markus767
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Quote:
Originally Posted by sdurani View Post

No, the units that did have loudness compensation didn't have that feature turned on. What Olive ended up comparing was the spectral balance (default target curve) of each unit and their ability to smoothen out the response (remove peaks and dips).
As a room correction designer, they couldn't guarantee a certain playback level, so they couldn't design a target curve with volume level in mind, which is why it wasn't part of the comparison. Likewise, they couldn't guarantee that loudness compensation would be applied (let alone which one -- Dynamic EQ, Dolby Volume, THX Loudness Plus), so they couldn't design a target curve with loudness compensation in mind, which is why it wasn't part of the comparison.
It was a comparison of room correction systems, not which playback level was most preferred and not which loudness compensation was most preferred. How could loudness compensation be built into the target curve when it isn't compensating for deviation from reference level?

What does equal loudness compensation do? It boosts bass (and highs). So if you look at the Harman curve, is it the result of listening at reference level or the result of the listening level at which Harman did their tests? As far as I can remember they don't do listening tests at reference level. So any subjective test has to end up with loudness compensation built into the tagret curve.
sdurani's Avatar sdurani
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Quote:
Originally Posted by sdurani View Post

the reason I don't use Olive's 2009 comparison to comment on current gear is because almost all the room corrections tested have evolved significantly since that comparison, including Audyssey, Anthem and Harman
Quote:
Originally Posted by craig john View Post

You make it seem as if Audyssey doesn't provide smoother and perceptually flat response. It does in *my* room:
You make it seem like I'm conflating the original MultEQ in their stand-alone box used in Olive's comparison with their latest XT32 that you're currently using in your room, even though I've explicitly stated the opposite earlier in this thread (see above). And, if you search my comments about XT32 in the Audyssey thread, you'll see that they were almost universally positive. So when we're discussing Audyssey in context of the Olive comparison, let's not pretend I'm making comments about XT32.
Quote:
Originally Posted by craig john View Post

Yeah, I know, they quoted their own research. While that's nice, it has about as much credibility as them testing another manufacture's product and finding their own product to be better. rolleyes.gif
Is there anything in either paper I linked to that was not factual? If you know of any research out there demonstrating that adding more speakers changes preference rankings, rather than making it more difficult to tell differences, then please post a link.
Quote:
Originally Posted by craig john View Post

It was also done by "trained" listeners, "trained" by Harman. eek.gif Of course, they're going to prefer the Harman sound.
You're misunderstanding what a trained listener is. When blind tested, they generally exhibit the same preferences as other listeners, they just arrive at those preferences with far fewer listening trials because they've practiced listening for timbral and spatial distortions (peaks, dips, etc).

There's an entire research paper that documents using 268 test subjects to compare preferences of trained listeners vs untrained listeners. Plus, you can download (for free) the training program to test (and improve) your ability to detect various types of distortion. Their research and their training program are wide open for you to scrutinize, so if you find something that is not factual, please post it.
Quote:
Originally Posted by craig john View Post

The measurements I posted above are not the raw post-Audyssey results. I changed all the crossovers, and I adjusted the subwoofer distance. In addition, I overrode the level-matching process and applied gain-matching to the subs. If Harman did none of those things, it's not surprising it wasn't preferred.
Was Harman supposed to do all those things? Are those steps mentioned in the Sound Equalizer instruction manual?
sdurani's Avatar sdurani
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Quote:
Originally Posted by Bigus View Post

Why are you asking me this question?
Because you brought up the particular room as a potential benefit for the Harman room correction:
Quote:
Originally Posted by Bigus View Post

Since the room was almost certainly used in tuning harmon's algorithm, you can rest assured there were no such quirks for their system. Hence, I'm not surprised their own solution performed well in their own room.
With that in mind, I was curious what type of room you believe would erase that benefit and level the playing field.
Quote:
Originally Posted by Bigus View Post

As a refocusing of your question, do you believe one room might prove difficult for one smoothing algorithm, whether due to some combination of measured location variances or otherwise, and not for another?
I don't believe that any room correction algorithm that is more capable of minimizing peaks and dips would somehow not maintain that capability when used in different rooms. That would be like pointing out that Lyngdorf had the advantge of a tilted response in their testing room but then asking me whether I believe it would still have that advantage in other rooms. How would it not? Not like that tilt is going to somehow disappear.
markus767's Avatar markus767
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Quote:
Originally Posted by sdurani View Post

That would be like pointing out that Lyngdorf had the advantge of a tilted response in their testing room but then asking me whether I believe it would still have that advantage in other rooms. How would it not? Not like that tilt is going to somehow disappear.

It could well be that different rooms need different target curves. In fact the X-curve used in movie theaters looks different than the Harman curve. So there is a more complex relationship between direct and reflected sound beyond simple steady-state measurements. Room curve as a metric is very much like RT. They are both of very limited usefulness in describing what is perceptually important.
sdurani's Avatar sdurani
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Quote:
Originally Posted by markus767 View Post

What does equal loudness compensation do? It boosts bass (and highs).
It boosts bass (and highs) based on deviation from reference. The Harman tilt wasn't tied to reference level, wasn't dynamic, didn't boost highs and wasn't shaped like any equal loudness curve ever published. How can it be loudness compensation?
Quote:
Originally Posted by markus767 View Post

So any subjective test has to end up with loudness compensation built into the tagret curve.
Except the Harman tilt didn't look anything like equal loudness curves. Olive says that the idea was make sure that naturally occurring room gain wasn't removed, which is the exact same reason Lyngdorf gave for their tilt. No mention of equal loudness in either case.
Quote:
Originally Posted by markus767 View Post

It could well be that different rooms need different target curves.
And Lyngdorf does adjust (based on room gain) for different rooms, but doesn't turn off that advantage (preserving room gain) in different rooms. Likewise, a room correction algorithm that does a better job of reducing peaks and dips won't stop behaving like itself just because it's in a different room.
markus767's Avatar markus767
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Sanjay

If you ask a test group to create preferred target curves for listening levels of 60dB SPL and for 90dB SPL using an equalizer then you will find that the resulting EQ curves differ. The amount they differ is the loudness compensation. Our loudness perception varies with SPL, that's a fact.
Bigus's Avatar Bigus
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Quote:
Originally Posted by sdurani 
I don't believe that any room correction algorithm that is more capable of minimizing peaks and dips would somehow not maintain that capability when used in different rooms.
You think every dmoothing algorithm will perform identically (wrt itself) in every room? Interesting. I have no proof that this isn't the case, but it seems unlikely.
Quote:
That would be like pointing out that Lyngdorf had the advantge of a tilted response in their testing room but then asking me whether I believe it would still have that advantage in other rooms.
Well, no, not like that at all. You're conflating the two processes. They aren't the same.

amirm's Avatar amirm
09:21 AM Liked: 547
post #926 of 3048
10-20-2012 | Posts: 18,377
Joined: Jan 2002
Quote:
Originally Posted by craig john View Post

amirm, you can drink, (and regurgitate), the Harman Koolaid all you want.
I have pretty good company Craig. Here is Dr. Kyriakakis and Bharitkar in their AES paper, "Objective Function for Automatic Multi-position Equalization and Bass Management Filter Selection"

"In fact, Toole et al. [16] have demonstrated that, based on steady-state measurements, low-Q resonances producing broad peaks in the measurements are more easily heard than high-Q resonances producing narrow peaks of similar amplitude."

Here is the referenced paper:

"[16] F. E. Toole and S. E. Olive, “The modification of timbre by resonances:Perception and measurement,” J. Audio Eng. Soc., vol. 36(3), pp. 122–141, March 1988."

Same Sean Olive whose testing we are talking about here. So if the creators of Audyssey reference their work, there is something to be learned there smile.gif.
Quote:
BTW, if you need some help learning how to integrate Audyssey into a high end system, let me know.
See ya...
Craig
Thank you for the kind offer. I have no doubt that you all have squeezed more performance out of Audyssey system. Take care Craig smile.gif.
rnrgagne's Avatar rnrgagne
09:54 AM Liked: 52
post #927 of 3048
10-20-2012 | Posts: 6,631
Joined: Jan 2003
Quote:
Originally Posted by sdurani View Post

"Various logos"? When Denon first introduced room correction in their receivers, who besides Audyssey was licensing that sort of technology to receiver manufacturers?

That I don't know, maybe Trinnov or TaCT's system ...but you could very well be right.
If I recall correctly I think YPAO was frst on the scene in consumer gear, then Harman's EZSet EQ so they likely wouldn't license to Denon, but who knows...

I still maintain there had to be some colaboration with engineers to incorporate the filters and time delays Audyssey uses into the DSP processes, not to mention the mic and it's pre-amp calibration.

.
arnyk's Avatar arnyk
10:22 AM Liked: 1178
post #928 of 3048
10-20-2012 | Posts: 14,387
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Quote:
Originally Posted by amirm View Post

I have pretty good company Craig. Here is Dr. Kyriakakis and Bharitkar in their AES paper, "Objective Function for Automatic Multi-position Equalization and Bass Management Filter Selection"
"In fact, Toole et al. [16] have demonstrated that, based on steady-state measurements, low-Q resonances producing broad peaks in the measurements are more easily heard than high-Q resonances producing narrow peaks of similar amplitude."
Here is the referenced paper:
"[16] F. E. Toole and S. E. Olive, “The modification of timbre by resonances:Perception and measurement,” J. Audio Eng. Soc., vol. 36(3), pp. 122–141, March 1988."
Same Sean Olive whose testing we are talking about here. So if the creators of Audyssey reference their work, there is something to be learned there smile.gif.
Thank you for the kind offer. I have no doubt that you all have squeezed more performance out of Audyssey system. Take care Craig smile.gif.

Excluded middle argument - nobody is doubting the general expertise of Toole, Olive and the other Harman speaker boffins.
sdurani's Avatar sdurani
10:46 AM Liked: 1030
post #929 of 3048
10-20-2012 | Posts: 19,904
Joined: Oct 2001
Quote:
Originally Posted by markus767 View Post

If you ask a test group to create preferred target curves for listening levels of 60dB SPL and for 90dB SPL using an equalizer then you will find that the resulting EQ curves differ.
Agreed, and the Harman tilt doesn't change to compensate for that difference, hence the conclusion that these tilts and downward sloping curves (from Lyngdorf, Harman, Dirac, DTS, etc) are that way in order to maintain natural room gain, not compensate for listening level. Those curves are not trying to duplicate the function of an optional feature (loudness compensation) that is always available to users if they choose to use it.
markus767's Avatar markus767
10:49 AM Liked: 372
post #930 of 3048
10-20-2012 | Posts: 5,508
Joined: Apr 2009
Sanjay, you're still ignoring the fact that those curves result from listening tests that were performed at levels below reference.

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