Axiom Home Page Forums General Discussion Technical Questions Equipment Burn-In -- A Scientific Test

i saw that same article about the bluff they pulled - kool
hey some people still believe elvis is alive

Here are some speaker parameters and their percentage change after a 3 hr. burn-in. These figures are from Partsexpress when they tested 3 randomly chosen woofers from an OEM batch.

Seem that these changes are significant.

(sorry about the format - just look close: parameter/value before/value after/pct change)

Before Break-In Average Post Break-In Average Percent Change
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Re(Ohms) 2.441 2.467 1.04%
Fs(Hz) 31.557 28.307 10.30%
Qms 9.826 9.547 2.84%
Qes 0.514 0.427 17.05%
Qts 0.489 0.407 16.79%
Mms(g) 124.773 133.903 7.32%
Cms(mm/ N) 0.205 0.237 15.71%
Vas(L) 33.050 38.087 15.24%
BL 10.770 11.737 8.98%
Le(mH) 2.546 2.480 2.57%
Sd(sq.m) 0.034 0.034 0.0%

Is there a link to this 'study'?

I would love to hear a pro comment on whatever these values listed are.

PartsExpress.com Then search for the Titanic MKII 10 inch woofer. Download the white paper from there. Also check out the glossary for a quick reference on the params.

Searching on "Thiel Small parameters" should yeald tons of sites with basic information.

Have fun!

In reply to:

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I'd like to see the exact same tests done with speaker wire to see if there is an actual, audible difference.

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One may measure differences between cables, but that alone says nothing about audibility. Also, the "exact same" tests are too simple to uncover differences between cables.

It should not be difficult to find published cable measurements as there have been many studies. The problem is, what kind of measurements are you looking for? Cables measurably differ in R, L, and C, but it cannot be easily correlated into how they will sound.

Considerations for setting up equipment to measure cables:

http://www.audioasylum.com/audio/cables/messages/41579.html
http://www.audioasylum.com/audio/cables/messages/41456.html

In reply to:

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Blind testing. It's about the best option the industry has to find out the truth.

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Although listening perceptions can be influenced by factors other than acoustic change, it does not automatically follow that blind listening is more reliable.

Yes:
"Cable Bibliography"
http://www.audioasylum.com/audio/cables/messages/12102.html

No:
(lists articles from professional journals)
http://www.audioasylum.com/audio/cables/messages/6127.html

Yes R, L, C, No everything else:
http://home.pacbell.net/drquad/jdunlavy.html

Review of Harrison and Duncan's "The Great Cable Test":
http://www.st-and.ac.uk/~www_pa/Scots_Guide/audio/cableshift/cp.html

Funny thing.
There seems to be alot more true scientific, journal articles proving no difference between cables and more unpublished, non-peer reviewed magazine articles that say there is a difference.
When i read words like 'digital jitter' i pretty much quit reading the article and know a salesman is in the house.
Sorry but this is one scientist that will stick with 50 cents a foot 12 gauge 99% copper wire as opposed to the $10 a foot, 12 gauge 99% copper wire.Blind testing. It's about the best option the industry has to find out the truth.

Adriel, I have to agree with chesseroo here. There have been too many instances in which cable differences have been described in extravagant terms which then disappeared a few minutes later when the listening became blind.

You appear to be somewhat subject to audio mythology. I recall your 2/15 post in Questions and Comments where you described a ringing in your ears and a metallic taste in your mouth while listening to the M2s. I gave the first reply( as Anonymous)with some helpful suggestions. This is a field which is rife with exaggerations and outright lies. Don't be fooled.

It's not that perceptions can be influenced by other factors, it's that they are influenced by other factors. The differences I'm looking for are in response tests. I don't care if the difference is good or bad, too subjective, just different. In order for one cable to sound different than another the sound coming out of the speaker it is connected to must be different. Once a change is noted, determination of the cause can then be done. If we know what causes what then one can say that one cable with these characteristics will sound like this with this type of speaker and so-on. Right now even the people that do believe in huge difference can't agree on what sounds best with what. Until true statistical analysis of the differences and similarities between blind test results and electrical characteristics of wire is done then this debate will always raise the blood pressure of both sides.

Daniel

Now there's a test.
How far will one's blood pressure go in attempting to determine if there is a difference by listening to the same damn test song 30 times over!?
ha