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In Reply to: RE: You keep changing your ground. posted by Pat D on October 18, 2010 at 05:03:15
which also includes the need for scientific validity. We already know the unverified assumption that the ABX box and its additional cables doesn't affect the results. Circular reasoning involves the use of more zip cord between each end of the *test*.
I'm learning from Tony about ignore lists. You just made mine.
Now you want to argue about something else. I have shown DBTs have been done on expensive cables--but I don't see you apologizing for saying mtrycrafts lied.
Now you bring up the alleged faults of the ABX box. But here again, you show you don't understand about the null hypothesis. You ask for proof that something makes no difference! You sometimes get it straight that the null hypothesis cannot be proven, but then you turn around and whine about it:
"We already know the unverified assumption that the ABX box and its additional cables doesn't affect the results."
You have a singular lack of evidence that it has any audible influence on the results. E. Brad Meyer has given me permission to post this text of his to AA:
"I understand that an old issue has arisen here concerning the supposition that the ABX box is not only audible when inserted into a signal chain, but also somehow spoils the sound passing though it, rendering previously audible differences inaudible. To anyone at all familiar with Ohm's law, this would be akin to magic -- and is certainly far enough out of the ordinary to be an extraordinary claim, requiring extraordinary proof. I am talking about proof that is required of those claiming audibility; it is certainly not a requirement for anyone conducting such a test to prove that the box is NOT spoiling the sound.
"Here are the facts: Instead of a six-foot connecting cable between the source and the line-level input, the signal goes through a three-foot cable, an RCA jack, an inch of hookup wire, a reed relay with a resistance of about 0.3 ohms (this is in a circuit where the input impedance at the far end exceeds 10 kOhms), though another inch of hookup wire to a second RCA jack, and then another three-foot cable. Yes, two sources are connected to the ABX relay module input. Only one at a time is connected to the output, and in any event having both connected is no different than having two sources connected to a preamp at the same time -- a configuration that I daresay describes virtually all systems out there.
"The original claim, in print, that an early version of the ABX box somehow ruined the sound was made in TAS by John Cooledge (not sure I spelled the name right but everyone remembers JWC). His assertion was entirely unsupported by any evidence other than his personal testimony, based on non-blind listening. I do not consider it credible given the electrical parameters involved. I can't prove he didn't hear anything, of course, but I can't prove that the universe wasn't created ten seconds ago, and neither question really interests me. If anyone wants to blind-test the box, I'd be happy to hear how that goes.
"If you don't think double-blind testing is necessary or helpful, well, perhaps you are the first person in history who can't be fooled, and good for you. But the experience of people who do try it has never, in my experience, been that the test setup changes anything. All the differences we or our subjects hear in sighted tests remain with the box in place, as long as we're just listening to A or B. It's just when X is pressed that things seem to get difficult. I have had a subject (this was in a demo at and AES convention) swear to me that what he heard when X was pressed was different from BOTH A and B, though A and B were the only sources around. And it doesn't really matter whether you use the box, either. That's just a convenience that makes it possible to do the test more easily. Hiding the source from yourself, by any means, is the essential, and the really vexing, thing."
"A fool and his money are soon parted." --- Thomas Tusser
The web page lacks basic detail. If one submitted this to a high school science lab back I went to school one would get an incomplete.
One needs complete documentation of the entire equipment set up, starting at the source material used for the tests, and including some kind of diagram of room. Listeners should be identified and described by experience. Other experimental parameters need be noted, e.g. setting of all control knobs on the equipment, physical location of ABX box, wiring lengths of all cabling, SPLs at the listening position(s), power levels out of the amplifier, etc. With this material it would be possible to begin talking about "evidence". Without it, results must be considered "anecdotal". Perhaps this material is available in someone's attic. Perhaps not.
This material would be evidence relating to what the listeners heard on one occasion. Additional testing and evidence would be required before this evidence would have value in a broader context. (This would include, for example, evidence that the test setup was sensitive to the matters to be decided and testing to qualify the listener and verify that their hearing was normal and they had been appropriately trained.)
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
If you search text "ABX" by me, you'll find nearly thirty times in the past (and you've responded) where I've pointed out the lack of controls used with ABX boxes. Try again.
E Brad can theorize all he wishes. Such does not constitute a scientific approach.
Oh yeah, you mentioned some assertions by Pass, which some knowledgeable people showed were not correct and did not actually reflect the ABX box circuitry.
"A fool and his money are soon parted." --- Thomas Tusser
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