Hi everyone.

During these past few years, there has been one controversy after another
discussed on the Stereophile (USA audio magazine) Chat Forum. The latest one
has been about whether applying a demagnetiser to LPs and CDs can give
actual improvements in the sound or, as has been argued in that forum
extensively, whether any effect experienced is merely 'auto-suggestion', a
'placebo effect', 'imagination', 'effective marketing' etc.

I have just replied to one person (giving Internet name "gdeering"), in the
thread titled "Re: Michael Lavorgna on subjectivists vs objectivists".

"gdeering" asked :-

>>> "Why do we assume that we are at a stage where what we measure relates
>>> to what we hear." <<<

I have copied my reply to "gdeering" below as it may be of interest also to
our PWB Forum members.

Kind Regards,

May

*******************

>>> "Spot on, Greg. Some people DO presume that what we can measure must
>>> relate to what we 'hear'. This is one of the major stumbling blocks in
>>> progressing forward in gaining an understanding of what might be going
>>> on.

The people who insist on 'measurements' as being able to give an ultimate
answer obviously believe that 'what is available to measure is heard in the
same way - i.e at the same volume, the same information, the same acoustics
etc. And, from that belief, then, any changes which people claim they can
hear MUST BE able to be measured - and, following on from that, any
measurement must follow the intensity of what was heard !! That then becomes
the brick wall !!

Let me give you an example from the subject which started this particular
controversy.

Michael Fremer described, in an article in Stereophile October 2006, that he
heard an improvement in the sound by applying a demagnetiser to LPs. Michael
said later:-

"What I heard was so obvious, so repeatable, so clear, it was like "is that
the Empire State Building?" Not "I'd better do an A/B/X to prove it really
is the Empire State Building" (I know that analogy is not valid). The point
is, not one skeptic---and I'm talking recording engineers, mastering
engineers whose names you know, and the editor of the magazine have all
heard the difference...."

Then, during a visit to Michael's in 2009, Stephen Mejias also heard an
improvement from a similar demagnetising demonstration by Michael and
Stephen said:-

"We only had time to try it with one LP, but, with that one LP, it made a
big improvement. There is a difference and it is obvious and it is
immediate. The applause at the very beginning of the LP sounds more like
real applause, more like pairs of human hands coming together to make sound,
and less like Styrofoam or static."

*********

We then had the 'measurers' coming into the discussion i.e such as AlexO
saying :-

>>> "If it can be heard, it can be measured." <<<

That, to me, shows that the people who are so insistent on 'measuring to
provide the answers' are not understanding well enough how people (human
beings) and their brains function.

It is a basic understanding amongst most scientists that human beings do not
'hear' exactly the same volume, the same information, the same acoustics etc
as the sound being physically produced. A microphone picks up the (acoustic)
sounds but the hearing/brain can discriminate - from exactly the same
information.

It has to be discriminate because the brain has to be economical with the
amount of energy it devotes to specific things. I can best describe this
from Richard Dawkins in "Unweaving the Rainbow" quoting Cambridge
physiologist Horace Barlow.

>>> "To summarize, it is as if the nervous system is tuned at successive
>>> hierarchical levels to respond strongly to the unexpected.

In Barlow's terms, it is the unexpected, it is 'news', and that is why we
register it.

>>> "a type of computer model, programmed by past experience and
>>> continuously updated by new sense data from millisecond to millisecond,
>>> are running inside the skull of every swimming fish, every galloping
>>> horse, every echo-ranging bat."<<<

>>> "We could say that the brain constructs a virtual world which is more
>>> complete than the picture relayed to it by the senses." <<<

>>> "It is as if the nervous system is tuned at successive hierarchical
>>> levels to respond strongly to the unexpected - and weakly or not at all
>>> to the expected.

To push the idea to an extreme, most of the time the brain does not need to
be told anything because what is going on is the norm. The brain is
protected from redundancy by a hierarchy of filters, each filter tuned to
remove expected features of a certain kind.

We see that the sensory coding units with which the brain confronts the
environment also constitute a statistical description of that environment.
They are tuned to discount the common and emphasize the rare." <<<

?

>>> "Everything that we know about the world outside our skulls comes to us
>>> via nerve cells whose impulses chatter like machine guns...... How would
>>> you translate information from the outside world say, the sound of an
>>> oboe or the temperature of a bath, into a pulse code ? The hotter the
>>> bath, the faster the machine gun should fire..... Actually this would
>>> not be a good code because it is uneconomical with pulses. By exploiting
>>> redundancy, it is possible to devise codes that convey the same
>>> information at a cost of fewer pulses..... To signal "It is hot, it is
>>> hot, it is still hot" by a continuously high rate of machine-gun pulses
>>> is wasteful; it is better to say "It has suddenly become hot". <<<

>>> "Most nerve cells are biased to respond to signal changes and programmed
>>> to exploit what is referred to as redundancy - screening out the
>>> wastefulness of energy. By using the term 'redundancy', it does not mean
>>> that the brain throws away information. The brain is told only about
>>> changes, and it is then in a position to reconstruct the rest" <<<.

**********

One example would be of a daily Newspaper and what headline it will print
each day.

It will not print the headline "The Sun rose in the East this morning" day
after day, because that is mundane - nobody would want to read that, nobody
would buy the Newspaper. But if they printed the headline "The Sun did NOT
rise at all this morning" or "The Sun rose in the West this morning" then
everyone would want to buy/read that Newspaper to find out what was
happening. THAT would be new - that would be rare !!

THAT would be taken notice of, would take on a greater importance than the
mere words used - but in pure 'measurement' terms the number of letters in
the different Newspaper headings would hardly be that different !!!!!!!

So, to come back to people's experiences when listening. If a person is
listening to their favourite disc, one they were used to, one which they
have heard many times, then their brain would be in some sort of 'ticking
over' mode - the disc is something they are used to, something they have
experienced being the same each time, the brain feels quite safe in being in
'ticking over/idling' mode but they then do something which gives a change,
which makes a difference in the sound they are used to. Suddenly the brain
is alerted, and goes into 'alert', 'what is going on' mode. Into Barlow's
"surprise", "unexpected", "news" - hence far more notice being taken of the
change !!! BUT a change has taken place, nevertheless !!!!!!!!!!!!

I can best quote Stephen again as an example of what I mean :-

>>> "We only had time to try it with one LP, but, with that one LP, it made
>>> a big improvement. There is a difference and it is obvious and it is
>>> immediate." <<<

Barlow's "surprise", "unexpected", "news" - triggering the brain to 'take
notice', 'it might be important' - hence Stephen's words. But not only
Stephen's words but similar words when other people have experienced a
similar thing !!! I.e "Something, suddenly, gave me an improvement in the
sound."

So, Greg, we have the people who are in the 'measurements will explain all'
camp. I.e If there are no changes in the measurements, then no changes have
taken place in the information, therefore people cannot have heard what they
say they heard.!!

And then you have the people who KNOW what they heard, who were taken by
surprise by what they heard. And there are many of those people, dotted
around the world !!

Hence the continuing controversy." <<<

*
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