yes by design of the stimulus in this very specific case. the time separation is simply how we can measure harmonics in a continuous sweep. it does of cause not break causality. This is why the separation of harmonics collapses at low frequencies (we need a very slow sweep to resolve down below 30Hz)
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The ASR "objectivists tribe" ;) has to read the Keynotes at the AES160th by Lars Risbo
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Which is not an issue. My current sweeps have 0.7 Hz resolution, plenty to resolve the low frequency response and distortion. And I could lengthen that even more if needed.
I am still not following why this is a reason to think distortion products in music reproduction are temporally dislocated.
I am still not following why this is a reason to think distortion products in music reproduction are temporally dislocated.
MaxwellsEq
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That is noise. Measurable in vision and sound.
Using ESS or stepped sine? ESS does not separate harmonics at very low frequencies. It requires a very slow sweep and it approaches a stepped sine. The 0.7 Hz is that from the FFTwindow length ? that is another thing.
I don’t recall ever saying that. It’s the case for an ESS sweep. A glissando or bird chirp might share some properties. This is all the open questions.
Sokel
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Bass glissandos were always a good acoustical (by listening) test back in the day, both for rooms and speakers.
(off-topic of course)
Then what are you saying??? How a measurement protocol separates distortion from the signal has nothing to do with audibility of said distortion.
No. It is computed from the CHIRP length. I really don't understand where you are going with this. Why do you need such specific, ultra high resolution distortion measurement in bass???
I enjoyed reading the article in general, but that section about the Farina Log Sweep is extremely misleading, actually outright wrong. I file that under "brain fart" that can happen even to the brightest minds. There is something missing between what we read and interpret and what Lars actually wanted to bring across. The wording didn't work out.
The ESS point is specifically about what it reveals about the ear’s temporal sensitivity — not a claim that music always has the same temporal structure as a sweep. Those are two different things.
the chirp length has nothing to do with the spectral resolution. you can use the shortest chirp and deconvolve 10 sec IR at get 0.1Hz resolution. The ability to resolve harmonics in the bass is a different story.
maybe you could elaborate more on why you think it’s wrong?
Quoting, "The exponential sine sweep, the standard method we use to generate THD plots, works by spreading harmonics out across time. The harmonics of the sweep arrive at the listener’s ear at different times."
(Bold mine)
When you listen to a slowly swept sine -- or constant sine for that matter -- all the harmonics of the current frequency are generated at the same time and we hear the corresponding "chord pattern". How could it not be like that, by what magic? It is not like when the signal passes, say, 100Hz fundamental you hear the 200Hz overtone at a different time (later, earlier?). But that's what you wrote, the way people are reading it.
What I think was going on in your mind might have been this: After the convolution with the sweep's inverse to obtain the impulse response from the recorded log sweep the harmonic pulses are separated from the main pulse and separated from each other, which is the beauty of the Farina method. Depending on sweep direction the harmonic pulse land before, or after, the main pulse. The second harmonic is spaced from the main pulse determined by the octaves-per-second sweep rate, H2 pulse is some time apart from the main pulse (and H3 is separated from H2 by a smaller time interval, and so on.. we all know Farina's seminal paper where this is explained). That also poses the restrictions on how far the block of data used for an FFT can stretch out before adjacent pulses bleed in.
However, we don't listen to that impulse response and If we did, we'd just notice that there are several pulses spaced apart, which don't have a distortion quality to them. They represent the distortion, of course. That's why your original statement does not make sense to the skilled reader and my thinking is you happened to mix things up, confusing the domains.
Therefore we hope you can clarify what you actually meant to say.
I'd like to see you prove it. You may have an observation or two, but how reliable are your senses in reality? Do you really see what's in the kitchen, or is your mind playing tricks? And are you sure that everybody who has ever lived, is living, or will live in the future will agree with you that there is no elephant in your kitchen? And if someone doesn't agree, then is your observation valid or is theirs? And how do you prove that?
Not sure there's anything new here from a measurement perspective. Delayed harmonics/IMD will show up in normal THD/IMD FFT plot just with different phase angles. I think it's really a psycho-acoustic claim that delayed harmonics generated by the driver are not masked by the original signal. This has more to do with the measurement and audibility testing of speaker drivers than any electronics, since any delayed echo in electronics will contain the signal and its harmonics, and so should be subject to the same critical bandwidth masking.
Buckchester
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I don’t agree with many of your points.
People on this forum trust measurements because they have been backed-up by rigorous science. The science involved both objective measurements and subjective listening. They found extremely strong correlations between the two. That is how we now know we can use objective measurements to predict subjective preference.
If some properly done double blind listening tests were done that demonstrated certain speakers consistently sounded better than others and could not be explained by existing measurements, I don’t think people here would dismiss that at all. They would be extremely curious and want to understand the results.
We now know what your agenda is. This objectivist label is misrepresented nonsense IMO.
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MatrixS2000
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Buckchester
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You’ve made some products that look remarkable. If you’ve developed something new to audibly improve people’s subjective preferences of speakers, demonstrate the evidence for that. Until then, I for one will remain sceptical.
hi, thanks yes i agree with your criticism. It is not as simple as i put it and I am probably to used to look at the deconvolved response. however, the deconvolution is simply a filtering operation which averages the chirp it self out save for one pulse. the harmonics and their time encoding is in the signal we hear.
Cheers
Lars
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Oh no I don't think so.
There would be accusing of cheating if no third party is integrated into the test process and so it would be very expensive and time consuming.
Revealing the name of the competitor speaker would cause bad blood. A comparison agains older speakers would not be considerd a propper comparison and can also cause bad blood nevertheless. A comparison with other speakers of the same company is more or less pointless.
It would be very likely a disaster marketing wise. A lot of money. Endless discussion which is typically good, but in this case it would be discussion within the scientific community only and all scientific standards would be checked rigorously, since this is how science works but average joe doesn't know this. The average joe thinks these kind of tests where done all the time and will take away the skepticis from the reaction of the audio science community.
No one has the money and resources to repeat the test. So there would be no third party validation...
Sorry but I think it would be expensive and really hard to get a good outcome out of it.
MattHooper
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I’m surprised at some of the replies by folks who otherwise appear to appreciate science.
So…let’s just abandon any pretence to scientific knowledge then?
What you’re doing here is exactly what I already headed off in my earlier response to Karmacoma HERE.
Perhaps you didn’t see it so I will just repeat it (with emphasis).
Remember that I was responding to the claim “it's impossible to prove that something doesn't exist, you can only prove that something exists,”
So in the context of empirical knowledge, the word “proof” was used.
As most people here would know,
in empirical fields “proof” is usually shorthand for “demonstrated to a high degree of evidential confidence,” not logical certainty.
Science doesn’t deal in deductive proof. It deals in evidence that reaches a level where the claim becomes the rational conclusion to accept. We’re not omniscient so empirical inferences have more to do with justifying confident levels in the context of possible error. In that sense pragmatism is a component of empirical claims to knowledge. (And everyday rational empirical inferences are continuous with this).
That’s why I replied:
“Under any practical understanding of empirical proof, I can prove to myself or to anybody who joins me that there isn’t a full-size bull elephant in my kitchen right now: By simply walking into the kitchen to observe the elephant is not there.
(to deny this conclusion, you’d have to place such high burdens on empirical proof that you also couldn’t prove something exists).”
So….when it comes to my (or anyone else’s ) ability to determine there is no elephant in my kitchen, the type of questions you imply need answering raises the burden of proof to an impractical degree. The same burden would undermine the ability to determine something exists in my kitchen. They are philosophy class 101 sceptical questions that are answered by the pragmatic version of empirical reasoning we use in science and to get through our daily life.
When scientists determine through observation/tests that the hantavirus is the pathogen responsible for the outbreak on the cruise ship, do you reject this because they haven’t established their senses as reliable?
“ how do we know all of you scientists aren’t hallucinating? And if you present evidence to us how do we know we are not hallucinating?”
Worse: are the scientists not justified in their conclusion unless “everybody who has ever lived, is living, or will live in the future will agree with you that hantivirus is on the cruise ship?”
Silly, right? No empirical conclusions could survive that burden for justification . There’s a good reason we don’t use untenable burdens of “proof” for our empirical conclusions.
Cheers
So…let’s just abandon any pretence to scientific knowledge then?
What you’re doing here is exactly what I already headed off in my earlier response to Karmacoma HERE.
Perhaps you didn’t see it so I will just repeat it (with emphasis).
Remember that I was responding to the claim “it's impossible to prove that something doesn't exist, you can only prove that something exists,”
So in the context of empirical knowledge, the word “proof” was used.
As most people here would know,
in empirical fields “proof” is usually shorthand for “demonstrated to a high degree of evidential confidence,” not logical certainty.
Science doesn’t deal in deductive proof. It deals in evidence that reaches a level where the claim becomes the rational conclusion to accept. We’re not omniscient so empirical inferences have more to do with justifying confident levels in the context of possible error. In that sense pragmatism is a component of empirical claims to knowledge. (And everyday rational empirical inferences are continuous with this).
That’s why I replied:
“Under any practical understanding of empirical proof, I can prove to myself or to anybody who joins me that there isn’t a full-size bull elephant in my kitchen right now: By simply walking into the kitchen to observe the elephant is not there.
(to deny this conclusion, you’d have to place such high burdens on empirical proof that you also couldn’t prove something exists).”
So….when it comes to my (or anyone else’s ) ability to determine there is no elephant in my kitchen, the type of questions you imply need answering raises the burden of proof to an impractical degree. The same burden would undermine the ability to determine something exists in my kitchen. They are philosophy class 101 sceptical questions that are answered by the pragmatic version of empirical reasoning we use in science and to get through our daily life.
When scientists determine through observation/tests that the hantavirus is the pathogen responsible for the outbreak on the cruise ship, do you reject this because they haven’t established their senses as reliable?
“ how do we know all of you scientists aren’t hallucinating? And if you present evidence to us how do we know we are not hallucinating?”
Worse: are the scientists not justified in their conclusion unless “everybody who has ever lived, is living, or will live in the future will agree with you that hantivirus is on the cruise ship?”
Silly, right? No empirical conclusions could survive that burden for justification . There’s a good reason we don’t use untenable burdens of “proof” for our empirical conclusions.
Cheers
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