Allow me to suggest a practical way to use the scientific method.

When testing a hypothesis of this sort (e.g. "Does de-gaussing a CD make 
a difference?"), it may be helpful to distinguish between two types of 

(1) We have the metrics to test the hypothesis (e.g. error rates). Then 
it is real.
(2) We have a panel of listeners who can test the hypothesis (in a 
well-designed blind ABX test).

There are three possibilities for case (2):
(2)(a) All members of the panel can tell the difference. Then it is real.
(2)(b) No members of the panel can tell the difference. Then it is 
probably hokum, until proven otherwise.
(2)(c) A subset of listeners (one or more) can consistently tell the 
difference. Then you can choose whether that subset of listeners is 
large or important enough to justify the expense or work for you.

Unfortunately there are no published tests for everything, so sometimes 
you have to perform your own blind test.

As an example, a paper published in the September 2007 JAES ("Audibility 
of a CD-Standard A/D/A Loop Inserted into High-Resolution Audio 
Playback", by E. Brad Meyer and David R. Moran) seems to prove that 
16-bit, 44.1 kHz is indistinguishable from high resolution audio to a 
panel of professionals and audiophiles. I am convinced --at least until 
someone comes up with a better study debunking this one.



Bruce Kinch wrote:
> On Jan 23, 2008, at 6:28 AM, Jerry Hartke wrote:
>> Some writers have technical skills, while others spin out profitable 
>> junk
>> for acceptance by gullible editors and readers.
> Full disclosure, I have been an a occasional reviewer for both print 
> and on-line audio journals. It is not a profitable avocation, and I 
> have never claimed technical expertise beyond that available to any 
> informed consumer. I don't consider anyone who investigates any issue 
> gullible per se, which is unfortunately the frequent opinion of many 
> who claim special knowledge in any field. That seems arrogant to me. 
> However, having access to CES and other venues, I have not 
> infrequently heard effects I cannot easily explain. Not all such 
> changes seemed to be improvements, and some that were hardly seemed 
> worth the cost. But then I drive a Mazda, not a Porsche for the same 
> reason. I have friends who disagree and preferred to pay the 
> difference. Are they gullible, or just happy?
>>  De-gaussing (there are no
>> ferromagnetic materials in a disc), polishing (introduces millions of
>> microscratches that distort the laser beam), and trimming (can worsen 
>> track
>> eccentricity or unbalance), have the potential to degrade, but not 
>> improve,
>> CD or DVD disc quality.
> The underlying assumption here is that a class of objects produced by 
> multiple agents at the lowest possible cost will have no functional 
> flaws that can be remediated after market. The only other consumer 
> category I can think of that makes such claims would be the purveyors 
> of religious texts - the Bible, the Qur'an, and whatever the 
> Scientologists keep by bedside and toilet.
>> If this remains an issue, Media Sciences would be
>> glad to participate in a controlled test on a few discs, both before and
>> after the "improvements", at no charge and then publish the results 
>> online.
>> Please contact me if you wish to participate.
> The logical fallacy here is to equate "disc quality" with the 
> perception of music. I switched from physics to psychology as an 
> undergrad because the girls in class were prettier. But I quickly 
> realized that while the physics lab experiments were straightforward, 
> experimental psych projects in perception had a lot of independent 
> variables that could not be controlled. I appreciate that in itself 
> can drive some people crazy.
> Again, there is ample documentation that some but not all auditioners 
> can and will hear a change from a variety of treatments, tweaks, and 
> widgets. Some perceive the change as a worthwhile improvement, others 
> don't. That is normal, not something to get huffy about. If you are 
> curious about such things, please do look into them.
> That this topic keeps re-surfacing, I suspect, is the result of a 
> certain lingering dissatisfaction among listeners familiar with the 
> sound of acoustic music in real space with the electronic and and 
> particularly digital reproduction of that music. The response is 
> essentially a desire to find something - anything -  that will ease 
> that disappointment. Tom Fine started the discussion by blaming the 
> engineering, not the technology, for the the problem. I take a broader 
> view, as I believe the limitations of CD reproduction are obvious in 
> comparison to higher definition digital as well as analog, to say 
> nothing of the real thing.
> Conversely, many folks (like my kids) who grew up listening to 
> amplified instruments and entirely digital media have different 
> criteria. They prize the loud, the clean, and the convenient. Here the 
> iPod trumps even the CD. The logical extension of a "bits iz bits"  
> definition of  perfect sound is to have the marketplace decide how 
> much more data can be thrown out and still fool a listener into 
> thinking it is music.
> Bruce