Ha! I was one of your customers for SigmaStat and SigmaPlot back then!
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"Things that cannot be measured"
- Thread starter ShiZo
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Science is also about understanding what the measurements mean, so this statement is certainly not out of place.
Even with the whole FR measurements we can observe different sound from speakers with reasonably similar FR. (Of course if the FR is too different the FR can predict with decent accuracy.) And when we can confirm and repeat the observation we continue looking for the reason why. That's how science progresses.
And the same single-number issue and room-and-preference issue can be said for subjective reviews too yea? Which is not too surprising, because the preference score is a subjective score. One backed by lots of data, but still a subjective score. The difference is this score is highly precise and reliable and obtained from controlled testing / measurement, vs a human reviewer, where even placing one speaker too high (my earlier days of testing while full of ignorance) totally ruins any accuracy of the subjective review.
I believe fundamentally there is no difference between a person doing a "measurement review / scientific review" or a completely subjective review, except the measurement guy knows more things and has more reliable methodologies.
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JSmith
Master Contributor
To clarify my previous statement, I do think the preference rating is generally more reliable than one random reviewer’s subjective review.
From my experience the preference rating when used on its own, for exampled to determine if one speaker sounds better than another can be very misleading.
I would not advise someone to purchase one speaker over another purely based on that score. If someone is not willing to read an objective review or simply does not understand it the score is only slightly more useful than reading several subjective reviews.
I would recommend someone in this case to read subjective reviews in addition to using the preferance rating. There are numerous cases where a speaker’s preference rating does fully reflect how good or bad a speaker sounds, especially in certain rooms.
rgdawsonco
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I've wondered about the OP's question from time to time. When I was in grad school a long time ago, we were studying pattern recognition and we spent some time learning about some of the mechanics of human perception. My thesis advisor had published a theory that the brain takes what it gets from the optic nerves and essentially performs a 2D Fourier Transform of the image, that is, the human visual system operates in Fourier space. This drastically reduces the storage requirements for visual information. This theory explained alot of things about our vision. Like, why optical illusions work they way they do. Like, why you can look at a bunch of vertical lines from a certain distance where you can determine that you are looking at a bunch of vertical lines, but you can't actually "see" any individual line. And many other question about how the brain does certain things so efficiently. (For those willing, this paper discusses the top, Physiologically-Based Pattern Analysis - ScienceDirect ). Anyway, we used 2D Fourier transforms, plus some other algorithms (based on what we thought the brain would do) to come up with pattern recognition algorithms that could recognize thngs like cars, planes, ships, tanks, and such no matter the view angle, the size, or the color, etc, like the brain does.
To me, this is a fascinating concept. Does the brain have similar algorithms for audio. How do we remember sounds? We certain don't store a recording of everything we've heard in our brain. That would cost too much. But we must store some encoded/transformed version of what we hear, similar to how vision works.
So when you look at the common optical allusion of two lines that are actually the same length, however one line has outward pointing arrows and the other inward pointing arrows, you can absolutely measure that and determine the lines are the same length. But after you do a 2D Fourier transform on them, one is clearly longer than the other and it is the same one that humans will say is longer (the illusion) when they look at them.
So, it could be that human hearing, like vision, is not just about what frequencies can be perceived and at what levels, but also how the signal is perceived after the brain does the transform on it, which it seems that it does. I'm sure if we knew exactly what the brain was doing we could measure what happens when we simulate that transform. But of course we don't. We know some kinds of noise/distortion are more audible than others, perhaps related to what happens in transformation. And perhaps there are combinations of things that are not well handled by our physiological encoders, be it for good or bad.
Another phenomena that has occurred to me is that a sound coming from dead center in a stereo image (phantom center) will not sound the same as the same sound played through the center channel assuming that the speakers and gear are all perfect. They might measure the same using a normal mic that does not have the gain patter of a pair of ears. That is due to the actual angle the sound is entering the ear and its gain pattern. This is why you just cant get a phantom center to sound like a center channel speaker, no matter what. Simply rotating or heads in any direction, even slightly, alters the sound. And how the sounds reflecting around the room really effect the sound.
So, yeah, I think there are things that cannot (or are not) measurable in practical terms that effect what we think we hear.
To me, this is a fascinating concept. Does the brain have similar algorithms for audio. How do we remember sounds? We certain don't store a recording of everything we've heard in our brain. That would cost too much. But we must store some encoded/transformed version of what we hear, similar to how vision works.
So when you look at the common optical allusion of two lines that are actually the same length, however one line has outward pointing arrows and the other inward pointing arrows, you can absolutely measure that and determine the lines are the same length. But after you do a 2D Fourier transform on them, one is clearly longer than the other and it is the same one that humans will say is longer (the illusion) when they look at them.
So, it could be that human hearing, like vision, is not just about what frequencies can be perceived and at what levels, but also how the signal is perceived after the brain does the transform on it, which it seems that it does. I'm sure if we knew exactly what the brain was doing we could measure what happens when we simulate that transform. But of course we don't. We know some kinds of noise/distortion are more audible than others, perhaps related to what happens in transformation. And perhaps there are combinations of things that are not well handled by our physiological encoders, be it for good or bad.
Another phenomena that has occurred to me is that a sound coming from dead center in a stereo image (phantom center) will not sound the same as the same sound played through the center channel assuming that the speakers and gear are all perfect. They might measure the same using a normal mic that does not have the gain patter of a pair of ears. That is due to the actual angle the sound is entering the ear and its gain pattern. This is why you just cant get a phantom center to sound like a center channel speaker, no matter what. Simply rotating or heads in any direction, even slightly, alters the sound. And how the sounds reflecting around the room really effect the sound.
So, yeah, I think there are things that cannot (or are not) measurable in practical terms that effect what we think we hear.
Anything that is psychologically based can't be measured because we don't know the exact transform occurring in your brain (or that it is the quite the same from one brain to another). Pain is an easy example. How might one objectively measure pain outside of one's own brain? All you can ever measure are physical phenomenon. These correspond, to a greater or lesser extent, to some psychological phenomenon. But until we have entirely explained brain processing in general and for a particular individual, we can't know the exact mapping. So anything psychological might be estimated through measurements. Some are easier to estimate with simple behaviors - for example, a just noticeable difference - and others are really hard because they are really just internal states - pain, emotion, color, etc. Pitch is the bit of hearing that is most divorced from the physical stimulus.
I would argue strongly that vision does not operate in Fourier space - that is an old theory. But it has not held the test of time. The "representational" theory of vision in which task-driven hierarchies of features produce "high-level" representations does a much better job accounting for the wide variety of data we have at this point in time. And consider the power of CNN's to account for visual representations. They would fail if vision were operating in Fourier space.
rgdawsonco
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Thanks for that. It was some 35 years ago I studied under Kabrisky, though I did not do my thesis work in this area and have not kept up with it. It was a cool theory at the time, but just a theory. My pondering was meant to be on idea that while we can measure things, we don't typically see or know what happens if/when we mimic the physiological information processing type function performed on signals by the human physiology. Too bad, if it is not accurate, because a certain monkey gave its life in the pursuit of science, when its brain was dissected while staring at an image and an approximate 2D Fourier transform of the image was reproduced from its brain. Yuck! (For the record, I was not part of that, I only saw the images.)
This is just my personal monologue.... maybe not suitable for this thread, but...
Once we have completed or become tired in certain amount of intensive objective measurements and subjective evaluation of "signals" and "sounds" with our audio gears, we need to stop it (at least for a while) and return to enjoying the "music" from the bottom of our hearts.
Otherwise, you will give your whole life to acoustic measurements and subjective evaluation of the "signal" and "sound", and you will give up and forget enjoying the "music" you love.
Once we have completed or become tired in certain amount of intensive objective measurements and subjective evaluation of "signals" and "sounds" with our audio gears, we need to stop it (at least for a while) and return to enjoying the "music" from the bottom of our hearts.
Otherwise, you will give your whole life to acoustic measurements and subjective evaluation of the "signal" and "sound", and you will give up and forget enjoying the "music" you love.
JSmith
Master Contributor
Agree... grab some well measuring gear, forget the other shit and just enjoy the tunes knowing you have a transparent system.
JSmith
JSmith
Master Contributor
For sure, one mans meat is another mans poison... each to their own etc. etc.
What some people call music I call whiny shit... then some people call some of my music nothing but noise.
JSmith
Agree... grab some well measuring gear, forget the other shit and just enjoy the tunes knowing you have a transparent system.
JSmith
Hello JSmith,
Thank you for your kind follw-up of my personal monologue.
Yes, that's why I recently started this relaxing thread after (provisional) completion of my audio system... really my "personal preference" thread in which several similar people are joining.
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mhardy6647
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As did we at my house
I used to refer to it as the My Weekly Reader of science (which I meant as a compliment).
rgdawsonco
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Definitely will check this out.
No, you are correct that the processing that happens in human physiology is a "black box" in many ways. It is impossible to just measure things and, from that, predict what the perceived differences (or not) will be. Consider pitch again. There is NO WAY in the input signal to deduce or measure pitch - one has to incorporate a psychological model to measure pitch. What one can say is:
1) If there is no measurable difference (using good equipment) between two signals, then there can't be a psychological (perceivable/audible) difference.
2) If there is a measurable difference, the only way to know if it matters is if one has the correct (and currently often unknowable) transfer function from inputs to experience.
3) Given all of the above, maybe the best way to see whether a measurable difference matters is to do (correctly, as alluded to in a recent video by Amir) double blind comparisons.
4) What really matters is your experience. We are complex, transient beings. If it makes you happy, it makes you happy. So if your best listening experience is listening to something that happens to measure terribly, but for whatever reason you enjoy the sound of that signal, then it is the best for you. Case closed. Doesn't mean it is the best by any standard but your own, but that is all that actually matters. If you like box wine, enjoy box wine.
Huh? How do electronic tuning aids work, then?
I think not. Pitch is the same thing as frequency (with a log scale, if you wish), and it is easily measured.
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