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
Ok you speak about "dissipation-driven adaptive organization," That does not contradict Schrodinger , that is a new interpretation of the second principle role in living evolutive system....And implicatin an organism in a new way with his environment, does not negate the specificity of life at all...Life is not reducible to the 2 principle. life incorporate it....

«Besides self-replication, greater structural organization is another means by which strongly driven systems ramp up their ability to dissipate energy. A plant, for example, is much better at capturing and routing solar energy through itself than an unstructured heap of carbon atoms. Thus, England argues that under certain conditions, matter will spontaneously self-organize. This tendency could account for the internal order of living things and of many inanimate structures as well »

This indicate that living system are not separate of the other system they are all linked in ONE universal system....That does not say that life is a machine because it self organize.... That go in my direction....All universe is living....
The fact that we can distinguish 2 things does not implicate the absolute separation of the 2.... Grammar 101

Saying "neuron has no precision" has no meaning....

saying neuron is sensitive has meaning...


Grammar 102
I think we are arguing about "precision" vs. "accuracy".  If I am sensitive to 1mV input, then my precision is 1mV.

If the brain is sensitive to one neuron, whatever its charge might be, then the brain is precise to that one unit of charge (coming from the neuron).

Now how accurate I am in counting how many "1mV" or how many unit of charge from the neuron, is something a bit different. 



I think we are arguing about "precision" vs. "accuracy"
It is heaudio that is arguing ...


I argue nothing....


Neuron is not precise is a sentence that has no meaning...

Neuron has sensitivity is the right sentence...


The rest is your his justification and arguing....
Heaudio ,Your reference to Jeremy England go in my direction....life is a universal fact, an organism and his environment are linked and there is no more separation between the 2 in a sharp line dividing living from non living....That complete Schrodinger and does not invalidate his reflexion….Life use the second principle.... He would rejoice to the idea....

The self organizing potential of matter is deeply buried in quantum mechanics and more profoundly in the mathematics of prime number theory.....Investigate the link between the crystals and quasi-crystals property of matter and primes numbers …..

By the way prime number distributions is the schematic pattern of the universal living memory....( my own reflexion) and the source of all information for all living system and even of the universe....

Prime numbers are not a rational fact or an irrational one....Prime numbers are a FACT more solid than the existence of any object in the universe... More complex than the universe itself....Mathematics are founded on a spiritual FACT, not on logic... There is no logic in Mathematics no more than in music, only a spiritual vision of the infinite, that man can communicate partially, using rationality, cutting some pieces to suggest the whole....The whole refracted in the prime number series is located in a non algorithmic universe that look like schematically like a quasicrystal or a musical piece...A musical piece is totally coherent and cohesive without being logical...Great mathematicians are always artistic spiritual and intuitive and creative....They create new world and new concepts...


life is not a machine in any way....