The Objectivist Audio Forum: Post #5 : Is Is Possible To Hear Something That Can't Be Measured?
Aug 16, 2008 at 8:11 AM Thread Starter Post #1 of 170

upstateguy

Headphoneus Supremus
Joined
Dec 20, 2004
Posts
4,085
Likes
182
This is a theoretical discussion.

It is common knowledge that we can measure things that cannot be heard, but is it possible to hear something that cannot be measured?

We can measure wow and flutter, and THD past the ability to perceive it. We can measure crosstalk you can't hear. We can measure attack and decay. We can measure ohms and amps and volts. We can measure higher and lower than human hearing can go. How is it possible that something in the limited audible range cannot be measured? And, if there is something there, what is it?

What do you think?

USG
 
Aug 16, 2008 at 11:43 AM Post #4 of 170
Maybe, maybe not. But for our purposes, I think measuring and hearing are not comparable. We measure things quantitatively (THD is higher or lower), while we hear things qualititatively (either it sounds better or it doesn't).
 
Aug 16, 2008 at 12:03 PM Post #5 of 170
Happens all the time.

Used to be all CD players were considered "perfect" but people still heard differences. No explanation until "jitter" was discovered.
Until then people were told it was "all in your head".

I'm sure the measurements still haven't caught up with everything that can be perceived by the human hear.
 
Aug 16, 2008 at 12:54 PM Post #6 of 170
"jitter" is just a word thrown around.
All cd players are different in a ways which can be MEASURED. Different analog output stage=different measurements.
 
Aug 16, 2008 at 1:49 PM Post #7 of 170
Science follows, not leads, human perception. We invent the measurements to understand perception, and then fit theories to the measuremens that are not exact. Finally we mathematically manipulate the formulas that follow from the theory to derive/predict new conclusions, which we then attempt to further verify with measurements.

Nothing prevents there from being a real-world condition that we cannot (yet) explain, as others here have noted. It is simply that our models are not good enough yet. You can predict that something is inaudible, but it is inaudible only if you can't hear it.

Posters mistake this all the time. They say "this is too low to be heard". That is not correct -- they mean "our current scientific models, proven to be accurate over years of testing, predict that this can't be heard".

That's why I like listening tests. But because of the placebo effect, and bias, and differences in hearing person-to-person, tests are not easy. And many believe that blind tests introduce bias of their own. Save this fight for another post.

Some examples of theory vs real-world:

It is a correct conclusion of standard audio waveform analysis that all songs never end -- they play for all time, and have been playing since the beginning of time (because the frequency response of your headphones is limited, therefore the Fourier transform of the frequency response curve-- which is amplitude vs time -- must be non-zero from minus to plus infinity ... or else if the music stops then your headphones go to 100KHz and beyond, to infinity).

This is obviously nuts, and many here know the answer -- the amplitude/time function and the freq response function are actually related by much more complicated transform theory -- but standard Fourier analysis is an extremely good approximation to reality, and is very useful.

Our models define attributes of an idealized circuit or sound transducer system that is a close, but not exact, description of reality. And our measurements measure something physical of course, again a close approximation to the attributes we just defined.

Neither the measurement nor the attribute are 100% correct, they are only models.

We are sure to discover more about human hearing and sound perception over the next n years. And then things will be clearer (pun).

For decades -- centuries actually -- we had no clue how homing pigeons found their way back. We worked on this at Bell Labs in the 70's. I mean really no clue. Of course the pigeons didn't care, they flew home. Scientists are now starting to understand the complex processes involved -- the pigeons are amazing.

High end gear makers think we are pigeons and will buy anything shiny that gets good reviews from reviewers with an economic interest in the industry. Bird poop on that -- let's test and test and test -- by listening, not measuring -- until the cows, and the pigeons, come home.
 
Aug 16, 2008 at 3:05 PM Post #10 of 170
[size=large]Hearing is measuring.[/size]
 
Aug 16, 2008 at 3:18 PM Post #11 of 170
Quote:

Originally Posted by upstateguy /img/forum/go_quote.gif
This is a theoretical discussion.

[...]is it possible to hear something that cannot be measured?



I think the previous postings are insightful, but they do not address the intent of the question. Rather, they focus on the practicalities of applying theory to reality.

But, from a purely theoretical point of view, I don't see how you can hear something that cannot be measured. We may not know how to measure it today, but we should be able to devise a way to measure it ultimately.

But this is only true of measuring the stimulus, not the response. Or at least that is as far as I am willing to go with it for now.
 
Aug 16, 2008 at 3:19 PM Post #12 of 170
Quote:

Originally Posted by Lazarus Short /img/forum/go_quote.gif
[size=large]Hearing is measuring.[/size]


Yes, but often not a precise form of measuring.
 
Aug 16, 2008 at 3:55 PM Post #13 of 170
Quote:

Originally Posted by Arjisme /img/forum/go_quote.gif
... I don't see how you can hear something that cannot be measured. We may not know how to measure it today, but we should be able to devise a way to measure it ultimately


Agreed, but how long is "ultimately"? How long between the first codification of gravity (1687 ... and gravity had been observed since the dawn of man) and strong interaction (1947 say, and its force had been observed like 40 years previously).

It takes time to notice something, and then additional time to fit a theory to it.

There may well be someting about listening to music that science as of now misses ... but listening test don't miss it, by defintion, which is why I left physics for statistics (OK, I lie: I am not smart enough to do physics, that was clear, and the stat department would have me!).

Your point about measuting stimulus vs response is fantastic -- I missed this totally. Great insight!! Electrodes implanted in the brain could provide very relevant response measurements, but we don't have the lab or the skills -- would be amazing statistics to analyze. Others have done this of course in the proper medical settings for research to help the deaf. I just didn't think of this, but you are 100% spot on. Unfortunately we can't act on this (I am thinking of a scene from Hannibal 3 -- the home-style brain surgery ...).

You really have an important point (although not a practical one). No doubt the brain location for placebo effect is easily differentiated from a real aural response. So in theory we could tell that someone "hears a difference" as opposed to "wants to hear a difference -- pleases him to hear a difference -- and talked himself into it".

Wow. You have given me a lot to think about. Be very afraid if I show up at a meet with a scaple.
 
Aug 16, 2008 at 4:08 PM Post #14 of 170
Quote:

Originally Posted by wavoman /img/forum/go_quote.gif
us vs response is fantastic -- I missed this totally. Great insight!! Electrodes implanted in the brain could provide very relevant response measurements, but we don't have the lab or the skills -- would be amazing statistics to analyze. Others have done this of course in the proper medical settings for research to help the deaf. I just didn't think of this, but you are 100% spot on. Unfortunately we can't act on this (I am thinking of a scene from Hannibal 3 -- the home-style brain surgery ...).

You really have an important point (although not a practical one). No doubt the brain location for placebo effect is easily differentiated from a real aural response. So in theory we could tell that someone "hears a difference" as opposed to "wants to hear a difference -- pleases him to hear a difference -- and talked himself into it".



That would only happen after we can fully understand how the brain wired itself first. Thought the general area of where is responsible to what has been mostly confirmed, we still don't know where precisely responds to 200Hz instead of 250Hz, or light green instead of dark green. This goes back to the Matrix: If you (or your brain in this case) are in a dream (or belief in this case) that is so real that you can't tell it is a dream or not, how do you know you are not in a dream? How would a tinnitus patient convince his brain that there is no sound? How would an amputee convince his brain phantom pain shouldn't exist?
 
Aug 16, 2008 at 4:55 PM Post #15 of 170
Quote:

Originally Posted by upstateguy /img/forum/go_quote.gif
This is a theoretical discussion.

It is common knowledge that we can measure things that cannot be heard, but is it possible to hear something that cannot be measured?

We can measure wow and flutter, and THD past the ability to perceive it. We can measure crosstalk you can't hear. We can measure attack and decay. We can measure ohms and amps and volts. We can measure higher and lower than human hearing can go. How is it possible that something in the limited audible range cannot be measured? And, if there is something there, what is it?

What do you think?

USG



I propose that it's not that we can't measure things that some can hear, but we've not yet learned "how" to quantify/measure/isolate everything that we can hear. We're getting closer and closer though. Our understanding of HRTF is pretty complete, for example, but we do not yet have total understanding of how someone's brain processes sound. I think also we can often overlook seemingly inconsequential things that many can hear, such as extremely minor deviations in frequency response, for example. Another thing to keep in mind is that we, as a species, are sometimes pretty good as comparators, but typically very poor in realizing absolutes, due to accommodation.
 

Users who are viewing this thread

Back
Top