[Powell]

"R. Stanton" wrote

Better than ABX?

"Better" than what?


ABX has become the standard test for comparison
of audio components.

Based on the periodicals that I'm aware over the last 30
years, no manufacture or audio magazine has ever used
ABX in product development or reviews. To imply
"standard" is to denote a battery of protocols in its use.
There are none to date do to a whole raft of
limitations/unknowns.


It is a valid test method, yet many people object to it.

That depends on the application. It is most successful when
differences can be detected as a result of its use. But it is
of no statistical practicality/significance when you generate
null data. Only proving that one can in fact discern the
difference is significant (arithmetic evaluation).


Their complaint is often: the ABX test makes it too hard to
hear differences between components.

True, but this doesn't necessarily rule out the device. One
must consider the psychological disposition, hearing acuity
and training of the subjects. There are many "standards"
(cross-checks) to limit or isolate the human influence
variable per say, but it is very expensive.


What if someone tries to cheat?

That's why the sample group size is significant.


1) Answers of: "sounds different" to all trials would give
a score of 50% correct.

Ok


2) Answers of: "sounds the same" to all trials would give a score
of 50% correct.

This data is discarded. Only proving that one can in fact
discern the difference is significant (arithmetic evaluation).


3) Totally random answers to all trials would give a score
of of 50% correct.

Ok... or the model wasn't designed suitably for the task
at hand.


A score of 50% correct indicates the subject can *not*
hear a difference. So cheating wouldn't work.

"*not* hear a difference"... an actual difference could
exist but the methodology may not be statistically sensitive
enough to discern it from the data.


I think the X-Y test would be easier on the subject, than the
ABX test, and would give a more accurate indication of
someones ability to hear a difference in the components.

Maybe, maybe not.