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Old 7th September 2004, 05:40 PM   #511
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If the error correction fails, you get outright errors, not subtle effects. Really nasty sounding errors.

So try again.
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Old 7th September 2004, 05:52 PM   #512
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Quote:
Originally posted by janneman
Think it through! "If the worst caps that we could find can't be detected" why does that AUTOMATICCALLY mean that the test is flawed? Why not conclude: 'It means that there is no audible difference'!
I would have to ask, why conclude that? Seems to me that such a conclusion would have to be based on the same sorts of preconcieved beliefs that has John concluding that the test is flawed.

Seems to me that the only firm conclusion that can be reached is that audible differences have yet to be proved.

se
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Old 7th September 2004, 05:54 PM   #513
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Quote:
Originally posted by geewhizbang
On a hard surface they don't make much sense. But they do look kewl.
I'm not so sure if they are "kewl" . The amp looks rather "funny" with them, and they are cheaper than quality rubber feet. So what exactly is your point here?

http://www.diycable.com/main/product...5a97bed60cb8f2

http://www.partsexpress.com/pe/showd...number=240-720
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Old 7th September 2004, 06:02 PM   #514
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Jan, I am now having my coffee, and let's hope that I can keep things on an even track. ;-) First, I feel that many on this thread have limited experience and knowledge to the accomplishments that we have made over the decades in audio design. Also, it is important that one actually has discussed ABX testing with the principal promoters of the test, in order to get as much understanding as possible about it, before deciding whether to use it or reject it. Many of you, who criticize me, don't seem to have 'walked the walked the walk, or talked the talk' that is necessary to have an informed opinion on the subject.
Folks, I must apologize when I 'brag' about my past published work, or that of others. It is easier to refer to it directly, rather than to give you an obscure reference, that most of you could never easily find, even if you wanted to bother.
In this case, it is important that I have done research on capacitor distortion and have published it, especially with regards to tantalum coupling caps.
As far as Thorsten is concerned: 'Keep on Truckin!'
For that degreed mechanical engineer who is so sure of his knowledge:
From 'The Experts Speak' once more: "I can accept the theory of relativity as little as I can accept the existence of atoms and other such dogma' Ernst Mach (Professor of Physics at the University of Vienna) 1913" p299
How about that? What a guy! Still, I have his textbook on my bookshelf.
Although I applaud anyone who has the drive to get a degree in engineering or physics, please learn your limitations. You will learn this from experience, soon enough. ;-)
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Old 7th September 2004, 06:08 PM   #515
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Konnichiwa,

Quote:
Originally posted by janneman
Completely wrong, Thorsten, I cannot believe you wrote this. Error correction is just that, error CORRECTION. After the error correction the data is 100% correct. Not 99.9999%, but absolutely 100%. Read '101 of CD players'.
I CANNOT BELIEVE that YOu wrote this! Are you COMPLETELY ignorant of how CD works?

Here a small Excerpt as to what I am on about (in short C2 and beyond):

Quote:
from http://www.cdrfaq.org/faq02.html#S2-17

"It is true that audio CDs use all 2352 bytes per block for sound samples, while CD-ROMs use only 2048 bytes per block, with most of the rest going to ECC (Error Correcting Code) data. The error correction that keeps your CDs sounding the way they're supposed to, even when scratched or dirty, is applied at a lower level. So while there isn't as much protection on an audio CD as there is on a CD-ROM, there's still enough to provide perfect or near-perfect sound quality under adverse conditions.

All of the data written to a CD uses CIRC (Cross-Interleaved Reed-Solomon Code) encoding. Every CD has two layers of error correction, called C1 and C2. C1 corrects bit errors at the lowest level, C2 applies to bytes in a frame (24 bytes per frame, 98 frames per sector). In addition, the data is interleaved and spread over a large arc. (This is why you should always clean CDs from the center out, not in a circular motion. A circular scratch causes multiple errors within a frame, while a radial scratch distributes the errors across multiple frames.)

If there are too many errors, the CD player will interpolate samples to get a reasonable value. This way you don't get nasty clicks and pops in your music, even if the CD is dirty and the errors are uncorrectable. Interpolating adjacent data bytes on a CD-ROM wouldn't work very well, so the data is returned without the interpolation. The second level of ECC and EDC (Error Detection Codes) works to make sure your CD-ROM stays readable with even more errors.

It should be noted that not all CD players are created equal. There are different strategies for decoding CIRC, some better than others."
To be precise about the points I was originally refering to:

Quote:
from http://www.cdrfaq.org/faq02.html#S2-17
If there are too many errors, the CD player will interpolate samples to get a reasonable value. This way you don't get nasty clicks and pops in your music, even if the CD is dirty and the errors are uncorrectable.
Some old players has outputs from the decoder which where puleld low if there where too many errors. They are no longer in existence. However, comparing the analogue output recorded from a CD player using a good quality soundcard with the raw data "ripped" from CD using bit accurate methodes with multiple reads is quite revealing too....

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Old 7th September 2004, 06:19 PM   #516
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I can't believe that rubber feet cost more than a few cents each. Let's get real. Your gold plated feet cost $5.00 each.
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Old 7th September 2004, 06:22 PM   #517
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Quote:
quote:
Originally posted by janneman
Think it through! "If the worst caps that we could find can't be detected" why does that AUTOMATICCALLY mean that the test is flawed? Why not conclude: 'It means that there is no audible difference'!


I would have to ask, why conclude that? Seems to me that such a conclusion would have to be based on the same sorts of preconcieved beliefs that has John concluding that the test is flawed.

Seems to me that the only firm conclusion that can be reached is that audible differences have yet to be proved.
I think what you have here is a microcosm of the problem most people have with scientific "proof"and causality. First, even proof that "A" causes "B" is difficult because even then certainty is never absolute; no mater how strong the evidence there is always the possibilty that the evidence will become weaker once a couple more decimal places of resolutioin can be achieved in measurement or that there may exist some "C" that causes both "A" and "B" which can be de-linked once "C" is understood.

If becomes more uncomfortable when we want to prove "A" does not cause "B". Strictly speaking, you can never say say this. The strongest statement is that no evidence has been found that supports "A" causes "B".

I thinks the average person is terribly uncomfortable with this state odf affairs. News media reflect this. You typically read "scientists have learned that. . ." . You you get the chance to talk to one of the people involved in the research about the strongest statement you will get is "Well, we're begining to think that . . ." or "The evidence seems to be pointing toward . . .".

A fairly small part of the population is comfortable with this state of afairs and can function with. An even smaller part wouldn't have it any other way - their worst nightmare is that all the questions get answered!

It's a minority od the population than operate on the basis that "A" (does not) causes "B" is subject to refution at any time but can comfortably make decisions and act as if it were certain.
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Old 7th September 2004, 06:24 PM   #518
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Quote:
Originally posted by geewhizbang
I can't believe that rubber feet cost more than a few cents each. Let's get real. Your gold plated feet cost $5.00 each.
So??
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Old 7th September 2004, 06:25 PM   #519
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Konnichiwa,

Quote:
Originally posted by janneman
Really? That would interest me definitely. Any pointers to where I could find this material?
Capacitor Blind testing was in a number of issues of HFNRR in the UK over the decades, among others.

Quote:
Originally posted by janneman
BTW, Thorsten, how come you answer the post directed to John, but not the one (501) directed to you?
After posting my answer to another item I scrolled upwards and first saw your post to John. I answered the other after I got out of a marathon meeting at work.

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Old 7th September 2004, 06:33 PM   #520
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Default I'D SWEAR I'VE JUST SEEN A RUBBER DUCK FLY BY...

Hi,

Quote:
I can't believe that rubber feet cost more than a few cents each. Let's get real. Your gold plated feet cost $5.00 each.
It's about money again, is it?

First of all pointy feet (spikes) are very effective at draining energy away form whatever is on top of them into the underlying surface.

So if you have a speaker with a mildy resonating cabinet the spikes will do that and they will also provide for a fixed reference from which the cones can throw out energy into the environment.
Conversely, speakers on rubber feet, while damping because if their inherent compliance, will do this much slower and they will not provide a solid basis for energy transmission.
IOW, they are lossy.
Then there are cones... While their way of dealing with energy transmission is similar to spikes but not really the same as they are made directional on purpose, etc, etc...
Remember, anything that can move will inevitably lose energy.

And that's just scratching the surface and taking the thread OT but just applied physics all the same: no money from the Randi Crew for that one I'm afraid.

Cheers,
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