"chung" wrote in message
news:AaL0c.95414$4o.117307@attbi_s52...
Harry Lavo wrote:
"Michael Scarpitti" wrote in message
news:Vzy0c.444501$na.1075235@attbi_s04...
"W. Oland" wrote in message
...


The ability of knowledge and/or belief to influence how a person
perceives
something is well established. For example, that is the reason that
placebos are used in the trials of new pharmaceuticals. Depending on
what
is being tested, up to 40% of the people taking the placebo report
improvement in their medical condition (and also side effects.) This
is
completely based on the =expectation= that the drug will make them
better.
As such, the "real" drug under test must do significantly
statistically
better than the fake one.

It cannot make a Harmon-Kardon amp sound consistently(!) different
from a Hafler amp, especially when I have no idea how each is supposed
to sound. It cannot make five different amps sound different from each
other, and consistently so.


The same thing applies to auditioning audio equipment, whether amps,
speakers, cables or whatever. If you know which piece of equipment
you
are
listening to at any given moment, your knowledge and beliefs about
that
item are going to influence your perception no matter how many times
you
tell yourself otherwise.

I have said this before, and I am going to say it again, for the LAST
time:

I had NO beliefs about how these amps were supposed to sound. It was a
'blind' trial, in the sense that I had not listened to any of the amps
before bringing them home for listening tests.

Hafler
PS Audio
Harmon-Kardon
Bryston
Sony

They all sounded different.

How can my 'beliefs' affect my judgement, when I had no 'beliefs' to
start with?!

I listened with Stax electrostatic earspeakers connected directly to
the power amps. Perhaps your system is not as critical.

But DON'T tell me I cannot hear differences between amps this way.
Hellen Keller could hear them!


Michael, I and others have described similar tests here under similar
conditions, and have always been told we are just imagining the
differences
based on "expectation bias". Expectant of what they can't say.

Unfortunately, some of the members of this forum, while intellectually
understanding it, have a difficult time differentiating between "sight
*may*
provide a bias that overrides true differences" with "sight *always*
overrides true differences and makes your comparison invalid".

This is a misrepresentation of those members' position. What some of us
are saying is that you have to be cognizant of the effects of
expectation bias, and take proper steps to control it , if you really
want to find out if there are *audible only* differences. We always have
said that if the differences are big enough, like those between
speakers, then you don't really need DBT's to differentiate them. We
don't say that "sight always overrides true differences" (in fact we
argue if the audible difference exists in the first place), we are
saying that expectation bias is very likely to override subtle
differences, and that DBT is the best way to control for expectation
bias. In the case of competent amps and speakers, we know that those
differences should be subtle at best, from measurements like frequency
response, distortion and signal-to-noise ratio tests.


What you are saying above is a very reasonable position. Unfortunately, it
seems to believed only in the abstract here. When somebody such as Michael
comes on saying he can hear differences in amps...there is no questioning
him on his listening conditions, no consideration of the age or circuitry of
the amps in question (despite one being a digital amp...the one chosen at
that). .no discussion of his stated purpose or state of mind. All that
happens is that he is told because he listened sighted, he is surely
imagining things. Then the turmoil ensues.

They should
know better, but they don't seem to be able to allow even the
possibility
that there are real differences and that you might have heard them.

No, they do, that's why they recommend the Harry Lavo's and Michael
Scarpitti's of this newsgroup to do controlled tests to see if those
differences are real. Heck, they even throw in real money to motivate
them, in the case of cables.


Insisting on a test that the "testees" don' t believe is valid. Nice
'gotcha.

So
don't get upset...it's a world view of theirs that you are not going to
change.

All you need to change their world view is to pass the cable DBT test!
. Simple, isn't it?


Sure, would greatly simplify the objectivist world-view here if we would
just go away and stop challenging the test.


But you can ignore them and instead focus on other topics of interest
here
on the forum.


I think the subjectivists actually find this topic of great interest,
based on how frequently they post in these threads...


You think the objectivists ever let an assertion of heard differences pass
without comment or challenge?