IM Distortion, Speakers and the Death of Science


One topic that often comes up is perception vs. measurements.

"If you can't measure it with common, existing measurements it isn't real."

This idea is and always will be flawed. Mind you, maybe what you perceive is not worth $1, but this is not how science works. I'm reminded of how many doctors and scientists fought against modernizing polio interventions, and how only recently did the treatment for stomach ulcers change radically due to the curiosity of a pair of forensic scientists.

Perception precedes measurement.  In between perception and measurement is (always) transference to visual data.  Lets take an example.

You are working on phone technology shortly after Bell invents the telephone. You hear one type of transducer sounds better than another.  Why is that?  Well, you have to figure out some way to see it (literally), via a scope, a charting pen, something that tells you in an objective way why they are different, that allows you to set a standard or goal and move towards it.

This person probably did not set out to measure all possible things. Maybe the first thing they decide to measure is distortion, or perhaps frequency response. After visualizing the raw data the scientist then has to decide what the units are, and how to express differences. Lets say it is distortion. In theory, there could have been a lot of different ways to measure distortion.  Such as Vrms - Vrms (expected) /Hz. Depending on the engineer's need at the time, that might have been a perfectly valid way to measure the output.

But here's the issue. This may work for this engineer solving this time, and we may even add it to the cannon of common measurements, but we are by no means done.

So, when exactly are we done?? At 1? 2? 5?  30?  The answer is we are not.  There are several common measurements for speakers for instance which I believe should be done more by reviewers:

- Compression
- Intermodulation ( IM ) Distortion
- Distortion

and yet, we do not. IM distortion is kind of interesting because I had heard about it before from M&K's literature, but it reappeared for me in the blog of Roger Russel ( http://www.roger-russell.com ) formerly from McIntosh. I can't find the blog post, but apparently they used IM distortion measurements to compare the audibility of woofer changes quite successfully.

Here's a great example of a new measurement being used and attributed to a sonic characteristic. Imagine the before and after.  Before using IM, maybe only distortion would have been used. They were of course measuring impedance and frequency response, and simple harmonic distortion, but Roger and his partner could hear something different not expressed in these measurements, so, they invent the use of it here. That invention is, in my mind, actual audio science.

The opposite of science would have been to say "frequency, impedance, and distortion" are the 3 characteristics which are audible, forever. Nelson pass working with the distortion profile, comparing the audible results and saying "this is an important feature" is also science. He's throwing out the normal distortion ratings and creating a whole new set of target behavior based on his experiments.  Given the market acceptance of his very expensive products I'd say he's been damn good at this.

What is my point to all of this?  Measurements in the consumer literature have become complacent. We've become far too willing to accept the limits of measurements from the 1980's and fail to develop new standard ways of testing. As a result of this we have devolved into camps who say that 1980's measures are all we need, those who eschew measurements and very little being done to show us new ways of looking at complex behaviors. Some areas where I believe measurements should be improved:

  • The effects of vibration on ss equipment
  • Capacitor technology
  • Interaction of linear amps with cables and speaker impedance.

We have become far too happy with this stale condition, and, for the consumers, science is dead.
erik_squires
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Only, only, if the validation by humans is reproducible under controlled conditions, otherwise it is just conjecture.
Ok take a piece of shungite around 500 grams, put it on the electrical central panel of your house, or anywhere in the audio system, the sound will change...For the worse or for the better.... The important thing is not fine tuning the effect for the time being, but only to induce an objective effect that is not measured …. This effect will be audible worsening or improving the sound by anyone putting it in his system and listening to a files that he knows already well.... After that observation of change, we will discuss how to improve this change and transform it in a definitive positive improvement in all case with any sound system? is it not simple?


By the way accusing all vendors a priori to be crooks is not only not fair diplomacy, it is plainly false on common sense ground judgment...

My self I replicate or create homemade all my tweaks... I dont buy any material that cost more than peanuts... The more costly electronic component I modified for my needs cost me 10 bucks...

There is no relation whatsoever between the audio system I owns now for years, and the same electronic components rightly embedded in the vibrational-resonant mechanical dimension, in my electrical grid, and in the acoustical fiel of my room.... Total transformation of the same speakers-dac-amplifiers....same electronics components but they produce a sound now at his real potential S.Q..... And you will said to me that is an illusion? I will smile for sure....

Try my experiment if you are serious about audio more than about dogmas... Is it too complicated to verify an audible change when putting a rock on an electronic component or on the electrical main box of your house ?
When you understand AI learning and architecture you realize in many ways that aspects are much like evolution and happening in real time. And yes, more creative that Beethoven and an even farther reaching mind than Einstein.
Remind me of 1980’s science fiction flicks :-) Watching too much of those can get you in trouble.

Fyi, 24/192 has 0 compromises within the limits of human hearing.
There is so much limitations even with today digital technology but talking about it would require talking about digital engineer that you may not be familiar with.  
When you understand AI learning and architecture you realize in many ways that aspects are much like evolution and happening in real time. And yes, more creative that Beethoven and an even farther reaching mind than Einstein.
You are right on only one aspect:

This apparent superiority is an illusion....The map is not reality, never mind the sophistication of the map...

"Far reaching mind" ? Goethe cannot be replicate, nor Bach, they are living organism that speak to other living organism.... A machine will speak numbers in so much complicated strings to another machine , no human mind can understand them not even their creators... But it is not something that have to be understood, it is a closed code between two machine or more  and synchronizing them....

A machine will live in a sea of numbers without being able ever to see numbers from the outside and creating concepts about numbers....( this is an important point about what is really a concept) Sorry it is elementary mathematics for the mathematical mind...Read Godel, Cantor, Ramanujan, Grothendieck, even Archimedes will do... One of the greatest genius to ever lived is Archimedes, and do you know what is his central idea? the concept of the infinite....(Reviel Nietz is specialist of Archimedes).

No machine will ever invent a concept? It is simple to know why.... To invent a concept you must live grounded internally in a universe, and you must at the same time see it from the outside.... I will not explain it here but this fact is the basic of linguistic and not only of mathematics...Read Ernst Cassirer, a philosopher and a scientist friend of Einstein, that discuss relativity with him, that know enough quantum mechanics to discuss with Bohr... Not an audiophile...:)

Life is among other things a universal connected cellular "active" infinite memory, and A.I. artificial memory, so powerful it will be, is nothing to compared with....By the way my ideas comes mostly from mathematics, but more sophistical ideas than just algorithmic theory for engineer...The mathematics linked to this universal memory of life are so new they are created 8 years ago by a Mathematician from Japan (Shinichi Mochizuki under the title Inter-universal geometry or arithmetic deformation theory)... Enjoy the read....And dont think audiophile are all stupid....I dont think that all engineers are stupid....