[Scott[_6_]]

On Feb 28, 4:04=A0am, Audio Empire wrote:
On Sat, 27 Feb 2010 14:13:49 -0800, Scott wrote
(in article ):

Yes we are saying the same thing and that's my final word on that aspect =
of
this subject.


And my final word is that we are not. There you have it.



=A0You asserted that DBTs were limited in use to
finding differences. They have a much broader range of use which
includes determining unbiased preferences.

No,

Here is what you actually said. "Like I said, DB or ABX tests are
really for finding differences, not for
determining which is better " So it is what you said.


I said that they aren't very good for making value judgements about the
quality of those differences.

I will accept that amended version. It is still completely wrong
though. Bias controlled preference tests are actually very very good
for making value judgements. And they are widely used for that
purpose.


I never said that they were limited to finding
differences.

Your words. " "Like I said, DB or ABX tests are really for finding
differences, not for
determining which is better "

But I was also thinking solely about audio DBTs when I wrote
that.

Irrelevant. Bias controlled tests can be single, double or even triple
blind. they are essentially all bias controlled tests just that double
blind is better at removing sublime biases than single blind. DBTs are
not only suitable for determining preferences they are ideal if one is
concerned about bias effects which are present in any and all
subjective preferences made without bias controls.


And for sure, the usefulness in audio is pretty much to finding
differences.


I'm thinkin Floyd Toole and Sean Olive might disagree given the
multimillion dollar facility they have at HK for doing blind
"preference" comparisons for speaker development.



You said all one needs for *most* products can be gleaned from a spec
sheet or simple demo. Apparently in *most* cases you are not concerned
with bias effects in one's process of choosing. Why the limited
concern for bias effects when they are always in play if not
controlled?

Because in most products, selection comes down to suitability to a need,
specifications, and personal taste.

And audio is different?

For instance a man with six kids is
likely not looking for a sports car to haul them around in. A guy who
commutes 100 miles a day to work, is unlikely to purchase a 14 MPG Dodge =
Hemi
Charger for that commute. A person who doesn't like brussels sprouts isn'=
t
likely to purchase a frozen entre containing them.

But audio is different.

Audio actually is no different. Bias effects are present in all
subjective perceptual evaluations.


People "think" they hear things (or get told that
they hear things) that simply do not exist (such as a difference in "soun=
d"
between a 1-meter throw-away Radio Shack interconnect and a $4000 1-meter
Nordost Valhalla interconnect or other obscenely priced piece of wire). W=
hen
subjected to a double blind test between these two, whereby sighted and
expectational biases are removed, and they hear no difference between the
two, then the totally honest audiophile will admit that he is wrong.



It has nothing to do with honesty and the fact is in many cases the
perception of a difference returns as soon as the bias controls are
removed. It is human nature not a matter of honesty.


On the
other hand, a man who says that two amps sound different and that his sup=
er
expensive Whiz-Bang 2000 sounds better than another amp can be vindicated
when the two are compared via a correctly set-up DBT. If he picks his
Whiz-Bang 2000 a statistically meaningful number of times, then we are le=
ft
with the overwhelming conclusion that that there probably is a difference
between the sounds of these two amps, and that he was right.


If "vindication" is the issue then we are talking about egos here not
audio.

What that DBT
fails to reveal, usually, is which one really sounds better.


It all depends on how a DBT is designed. why anyone would bother with
anything that is not geared towards preference is beyond me. well,
actually it isn't. It is the test of choice for those consumed with
debating these things.


That's often a
question of taste, and DBT's aren't very good at determining that aspect =
of
the differences in the sound of two DUTs from a taste standpoint


As said before, you are plainly mistaken on that matter.DBTs are very
very good for making bias controlled determinations of subjective
preferences. Further more, logic dictates that the best use of blind
protocols in the auditioning process would be when making a choice
between components that actually sound different since there is no
wrong choice sonically between components that sound the same. Ironic
that the vast majority of DBTs don't actually make use of them in
their own choices when they are of the most use. Clearly, this is
where we disagree.