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Serious Question: How can DAC's have a SOUND SIGNATURE if they measure as transparent? Are that many confused?

tuga

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The listeners in the study were mostly people with professional experience in audio, some "trained" by Harman and other not. This is obviously a major shortcoming of the study.

Why do you think so?
 
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raistlin65

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Could you elaborate on this? The 2013 study found that, when presented with a speaker that had been equalised to not be flat, listeners EQ'd it themselves so that it was flat (from 250Hz upwards).

You understand superlatives in grammar, right? "he didn't say almost flat" he said "the flattest."

Firstly, I would not expect a player in the market to share which speakers were studied, as it would potentially open them up to the risk of litigation.

I have heard people say that before. IANAL, but the claim seems more of a loyalty defense of Olive to me. My guess is that it's more of (a) they didn't want to advertise the neutral speakers in the study that did well that were not Harman or (b) the problems with the selection set were worse than they let on.

Secondly, the original studies were clear on the fact that the non-neutral speakers in the study had other issues, as you put it. This is not some hidden piece of information that was only revealed post facto.

It's been so long since I looked at that paper, and I no longer have access. Can you quote the relevant portion about the speaker issues?
 

JohnYang1997

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Other studies have failed to find this is audible in the magnitude in which it is present in conventional speakers, except insofar as it effects amplitude response.

In isolation from that, it's either negligible or completely irrelevant.
Phase is really audible. Not to the extent it's distorted but easily audible. The imaging and shape of sound stage changes. When using linear phase filter to change eq feels like the sound doesn't change in some way while minimum phase is much more responsive and change the sound stage accordingly. I also tried to use a minimum phase cascaded by a linear phase filter to correct the phase itself without changing magnitude response. It's easily audible.
 

Wes

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how many DACs don't have a flat FR? (not that FR of speakers isn't an interesting topic)

if there is a difference in sound that can be discerned among DACs it must be due to something else

tho listening tests to determine if there is indeed a discernible difference in sound are what's needed
 

andreasmaaan

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You understand superlatives in grammar, right? "he didn't say almost flat" he said "the flattest."

I thought we were being friendly and constructive here; I interpret this question as snide. Can we agree to be respectful please? :)

In answer to your question, no pair of speakers can achieve anything like the preferred in-room response without equalisation, whether flat or not, because primarily the room and not the speakers determine the in-room response below 300-500Hz. So the flattest speakers do not perform worse than less flat speakers in this region (neither flat nor non-flat speakers are the primary determinants of the response).

If there is no advantage to a speaker's being non-flat in this region, and non-flat speakers perform worse than the flattest speakers in other regions, then yes, the flattest speakers perform best.***

I have heard people say that before. IANAL, but the claim seems more of a loyalty defense of Olive to me. My guess is that it's more of (a) they didn't want to advertise the neutral speakers in the study that did well that were not Harman or (b) the problems with the selection set were worse than they let on.

Could well be. I'm not in a position to know. Whatever the reason, I don't see the fact that the identities of the speakers were not disclosed as problematic for the validity of the study (but as we've discussed, I agree that there are other problems).

It's been so long since I looked at that paper, and I no longer have access. Can you quote the relevant portion about the speaker issues?

I'm not sure which specific paper you're referring to, as there were a number of them. In this 2003 paper, which to my knowledge marked Olive's first serious foray into this enterprise, the authors state:

"A sample of 13 loudspeakers was selected from the 23 different models reviewed in the August 2001 edition of Consumer Reports... The speakers are coded as S1 through S13 since the brand and model numbers are not relevant to this study... The selection included samples from the top, middle and bottom ranks of CU’s test scores priced from $100 to $450 a pair. All are 2-way bookshelf models except S9, which uses a single driver."

In part two of the same study in 2004, they state the following:

"The selection of 70 loudspeakers was based on the competitive samples purchased for performance benchmarking tests performed for each new JBL, Infinity and Revel model. The price range of samples varied from $100 to $25,000 per pair and includes models from 22 different brands from 7 different countries: United States, Canada, Great Britain, France, Germany, Denmark and Japan. The loudspeakers included designs that incorporated horns and more traditional designs configured as 1-way to 4-ways. Some used waveguides, while others did not. The sample also included four professional 2-way active models referred to as “near-field” monitors. The vast majority of the speakers were forward-facing driver designs, with one electrostatic dipole sample."

***Again, please let me make it crystal clear that when I say "best" I mean according to the best evidence that is presently available. I remain open to these findings being challenged or refuted, and I welcome any new data that might do this. But I don't welcome statements that the findings are wrong that are not based on better, or at least other, evidence.
 
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Wes

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really? I had no idea there was that much variation.
 

andreasmaaan

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Please demonstrate how the 2004 study is larger than the BBC study of 1958 and all the research built on that study.

http://downloads.bbc.co.uk/rd/pubs/reports/1958-31.pdf


Thanks.

I don't mean to denigrate from that report and the studies that it refers to, since it was obviously extremely important and well-researched, but as far as I can tell, it is primarily an in-depth analysis of objective aspects of loudspeaker performance, and not an investigation into listener preferences. Or have I missed/misunderstood something?
 

andreasmaaan

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Phase is really audible. Not to the extent it's distorted but easily audible. The imaging and shape of sound stage changes. When using linear phase filter to change eq feels like the sound doesn't change in some way while minimum phase is much more responsive and change the sound stage accordingly. I also tried to use a minimum phase cascaded by a linear phase filter to correct the phase itself without changing magnitude response. It's easily audible.

Yes, phase is audible. I didn't say it wasn't. It's just that the thresholds are higher than many seem to believe them to be.

And indeed, phase shifts are highly audible - as you are making them. Once a new transfer function has been locked in, sensitivity to the differences drops back to the levels I briefly outlined in my post above.

Or do you have a study that refutes the statements I made in my earlier post?
 

mansr

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really? I had no idea there was that much variation.
It can be a lot worse too. Case in point, the Dragonfly Cobalt:
1582202284644.png
 

raistlin65

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I thought we were being friendly and constructive here; I interpret this question as snide. Can we agree to be respectful please? :)

In answer to your question, no pair of speakers can achieve anything like the preferred in-room response without equalisation, whether flat or not, because primarily the room and not the speakers determine the in-room response below 300-500Hz. So the flattest speakers do not perform worse than less flat speakers in this region (neither flat nor non-flat speakers are the primary determinants of the response).

If there is no advantage to a speaker's being non-flat in this region, and non-flat speakers perform worse than the flattest speakers in other regions, then yes, the flattest speakers perform best.***

So now you seem to be saying no speaker can be said to sound better than the other because of room interaction. I guess we'll have to disagree here.

I'm not sure which specific paper you're referring to, as there were a number of them. In this 2003 paper, which to my knowledge marked Olive's first serious foray into this enterprise, the authors state:

"A sample of 13 loudspeakers was selected from the 23 different models reviewed in the August 2001 edition of Consumer Reports... The speakers are coded as S1 through S13 since the brand and model numbers are not relevant to this study... The selection included samples from the top, middle and bottom ranks of CU’s test scores priced from $100 to $450 a pair. All are 2-way bookshelf models except S9, which uses a single driver."

In part two of the same study in 2004, they state the following:

"The selection of 70 loudspeakers was based on the competitive samples purchased for performance benchmarking tests performed for each new JBL, Infinity and Revel model. The price range of samples varied from $100 to $25,000 per pair and includes models from 22 different brands from 7 different countries: United States, Canada, Great Britain, France, Germany, Denmark and Japan. The loudspeakers included designs that incorporated horns and more traditional designs configured as 1-way to 4-ways. Some used waveguides, while others did not. The sample also included four professional 2-way active models referred to as “near-field” monitors. The vast majority of the speakers were forward-facing driver designs, with one electrostatic dipole sample."

So this conversation began where I posted what Sean Olive said about the 2004 research on loudspeakers and the issue with the non-neutral speakers in the study. Here is one place I quoted it: https://www.audiosciencereview.com/...as-a-sound-signature.9245/page-39#post-331868

Here is the link to the study: http://www.aes.org/e-lib/browse.cfm?elib=12847

Now you said,
Secondly, the original studies were clear on the fact that the non-neutral speakers in the study had other issues, as you put it. This is not some hidden piece of information that was only revealed post facto.

So I asked if you can quote the relevant information that makes that clear, that the non-neutral speakers have those issues, as I do not have access to the research. Where in that study does it say that the non-neutral speakers had those issues. I'm not seeing it in that text above that you quoted. Or, if someone can provide a link to that 2004 study that is not behind a paywall, I would be glad to take a look at it.
 

andreasmaaan

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So I asked if you can quote the relevant information that makes that clear, that the non-neutral speakers have those issues, as I do not have access to the research. Where in that study does it say that the non-neutral speakers had those issues. I'm not seeing it in that text above that you quoted. Or, if someone can provide a link to that 2004 study that is not behind a paywall, I would be glad to take a look at it.

"A sample of 13 loudspeakers was selected from the 23 different models reviewed in the August 2001 edition of Consumer Reports... The speakers are coded as S1 through S13 since the brand and model numbers are not relevant to this study... The selection included samples from the top, middle and bottom ranks of CU’s test scores priced from $100 to $450 a pair. All are 2-way bookshelf models except S9, which uses a single driver."

"The selection of 70 loudspeakers was based on the competitive samples purchased for performance benchmarking tests performed for each new JBL, Infinity and Revel model. The price range of samples varied from $100 to $25,000 per pair and includes models from 22 different brands from 7 different countries: United States, Canada, Great Britain, France, Germany, Denmark and Japan. The loudspeakers included designs that incorporated horns and more traditional designs configured as 1-way to 4-ways. Some used waveguides, while others did not. The sample also included four professional 2-way active models referred to as “near-field” monitors. The vast majority of the speakers were forward-facing driver designs, with one electrostatic dipole sample."

See bolded passges. The study is written for professionals in the industry, not the ignorant. To anyone with any knowledge of loudspeaker design, it would be abundantly clear that the sample included many speakers with "issues".

So now you seem to be saying no speaker can be said to sound better than the other because of room interaction. I guess we'll have to disagree here.

No. Please re-read my previous post. I don't know how to spell it out more clearly.

Also please note that the listeners in the 2013 study applied an additional bass boost in more or less precisely the same region in which the test speaker's bass rolled off, bringing the test speaker to flat, +/-2dB, 30Hz-20kHz.

1582208611232.png
 

raistlin65

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"A sample of 13 loudspeakers was selected from the 23 different models reviewed in the August 2001 edition of Consumer Reports... The speakers are coded as S1 through S13 since the brand and model numbers are not relevant to this study... The selection included samples from the top, middle and bottom ranks of CU’s test scores priced from $100 to $450 a pair. All are 2-way bookshelf models except S9, which uses a single driver."

"The selection of 70 loudspeakers was based on the competitive samples purchased for performance benchmarking tests performed for each new JBL, Infinity and Revel model. The price range of samples varied from $100 to $25,000 per pair and includes models from 22 different brands from 7 different countries: United States, Canada, Great Britain, France, Germany, Denmark and Japan. The loudspeakers included designs that incorporated horns and more traditional designs configured as 1-way to 4-ways. Some used waveguides, while others did not. The sample also included four professional 2-way active models referred to as “near-field” monitors. The vast majority of the speakers were forward-facing driver designs, with one electrostatic dipole sample."

See bolded passges. The study is written for professionals in the industry, not the ignorant. To anyone with any knowledge of loudspeaker design, it would be abundantly clear that the sample included many speakers with "issues".

Yeah. I'm not ignorant. I can see that the quoted explanation does not provide evidence that the test was not biased towards neutral speakers. It does not state that the distribution included non-neutral speakers that were comparable in quality of design other than the difference in frequency response.

So I would be curious to see the paper for that 2004 study if someone knows of a link.
 

andreasmaaan

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Yeah. I'm not ignorant. I can see that the quoted explanation does not provide evidence that the test was not biased towards neutral speakers. It does not state that the distribution included non-neutral speakers that were comparable in quality of design other than the difference in frequency response.

So I would be curious to see the paper for that 2004 study if someone knows of a link.

IIUC, you're speculating that in the 2004 studies, Olive biased the speaker sample selection (either intentionally or unintentionally) so that all or most of the neutral speakers did not have other issues, and so that many or most of the non-neutral speakers did.

Did I understand you correctly?

If so, what I assume you're saying is that you won't be satisfied until (a) Olive releases information about which speakers were tested and how they rated, along with full anechoic measurments, or (b) a study is done in which speakers with few issues other than a non-neutral frequency response are compared to neutral speakers.

Correct?
 

TomB19

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Let's see the complete study with full detail.

Without that level of openness, his ideas are interesting but of no objective value.
 

andreasmaaan

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Let's see the complete study with full detail.

Without that level of openness, his ideas are interesting but of no objective value.

What details other than the models of speakers would you like to see?
 
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