Fuses that matter.

04-28-12: Geoffkait
There are obviously many reasons why someone might not get the expected results, including impaired hearing, lack of listening experience, faults somewhere in the system, failure to follow instructions, etc. Thus, negative results mean precious little, except to support claims by naysayers that the device under test disobeys all known laws of science, is fraudulent, or is simply a placebo.

On the other hand, positive results don't mean much either, unless:

A)The assessment was conducted in a sufficiently disciplined manner, and with sufficient understanding of the variables that might affect the results, such that there can be a reasonable degree of certainty that the result is being attributed to the correct variable.

For example, extraneous variables that could conceivably affect assessment of a fuse, especially one that is claimed by some to require 100 hours of breakin, would include ongoing aging, breakin, loss of breakin or rebreakin of system components; equipment being in a different state of warmup during the different parts of the comparison; differences in contact integrity resulting from removing and replacing the fuse, including scraping away of oxidation that may occur, as well as differences in contact pressure; changes in AC line voltage or noise conditions; changes in room temperature (temperature is a parameter that is fundamental to the physics of transistors and other semiconductor devices); and changes in RFI/EMI conditions.

B)There is sufficient understanding of the mechanisms by which the device works, if in fact it does work, to provide confidence that its effects are not just a quirk of its interaction with the particular system, that would not occur in many or most other systems.

For example, a finding that a fuse makes a difference with a Class AB or Class D amplifier, for which the AC current draw fluctuates dramatically as the volume of the music varies, IMO would say nothing about the likelihood that it would make a difference with a Class A amplifier, for which there is little fluctuation in AC current draw.

C)The assessment was conducted in a sufficiently disciplined manner to rule out the possibility of misperception, placebo effect, or self-reinforcing mass hallucination (a la the stock market, ca. 2000). As a minimum, that would mean going back and forth at least a couple of times between the devices being compared, to verify that the results are repeatable. In saying that, I am not necessarily referring to an immediate ABX-type back and forth comparison, since I recognize that not all differences will be perceivable in a short-term comparison.

04-28-12: Bryoncunningham
What is the standard by which Possible Unknown Parameters are distinguished from Impossible Unknown Parameters?

As with most things in life, IMO it comes down to judgment, hopefully judgment that is as informed as possible. Informed by a combination of technical understanding, experience, and inputs from others. While judgments will certainly differ considerably from person to person, it is all that we have to go on. In applying that judgment, we weigh what we consider to be the likelihood of significant benefit against the time, expense, and potential risks and downsides (see the link Clio provided) that are involved in pursuing it.

FWIW, my own "a priori," subjective, and certainly fallible judgment is that the possibility of a fuse making a sonic difference falls within the realm of a Possible Unknown Parameter, while its directionality does not. In saying that, I certainly do not exclude the possibility that cables (as opposed to fuses) may have directional sensitivity, the two situations being distinguished by the vastly different lengths that are involved, by the less direct relation between a fuse and the signal path, and by the fact that many cables are asymmetrical by design (with the outer shield being grounded at only one end).

Best regards,
-- Al

Almarg, for what it's worth, I agree. I certainly think that mankind lacks total understanding of how the universe works and in fact when it comes to quantum physics may lack the capability to understand. Any one who believes that all wires sound the same, all capacitors sound alike, etc. just isn't listening with normal ears.

04-28-12: Almarg
...my own "a priori," subjective, and certainly fallible judgment is that the possibility of a fuse making a sonic difference falls within the realm of a Possible Unknown Parameter, while its directionality does not. In saying that, I certainly do not exclude the possibility that cables (as opposed to fuses) may have directional sensitivity...

I agree. As I said in my last post...

...the idea that wires are directional or that fuses can affect sound quality, while they may be outside the scope of prevailing knowledge, fall within the scope of possible knowledge.

I mentioned *cable* direction but I deliberately left out *fuse* direction, which I doubt is a Possible Unknown Parameter. But I don't have a particularly informed judgement about fuse directionality either. Speaking of informed judgment...

IMO it comes down to judgment, hopefully judgment that is as informed as possible. Informed by a combination of technical understanding, experience, and inputs from others. While judgments will certainly differ considerably from person to person, it is all that we have to go on.

I agree with this, Al, as a general statement of what we must rely on to distinguish Possible Unknown Parameters from Impossible ones. Your last post also gives me a better idea of some of the specific factors that influence your judgments. I'd be interested to hear from other folks as well about what specific factors influence their judgments. It interests me both as a philosophical question...

--How do you decide when something is worth exploring?

...and as a practical question...

--How do you decide when something is worth experimenting with?

There's of course a great deal of variation among audiophiles on these two questions. Personally, I like to explore and experiment with a wide range of things, including some things that fall into the category of Magic. I like to think it's out of curiosity, though some will say it's out of gullibility. So my own answers to the questions above are...

--A thing is worth exploring if it is reported by either (a) a single source of known credibility OR (b) multiple sources of unknown credibility. And...

--A thing is worth experimenting with if (c) it meets condition (a) or (b), AND (d) it doesn't strike me as deception or insanity.

IMO, both cable directionality and fancy fuses meet conditions (c) and (d), and so fall into the category of Possible Unknown Parameters. But I respect that other people arrive at these decisions differently.

04-28-12: Geoffkait
The problem with the argument that "innumerable" people, even experts, are wrong is that there only needs to be one person, expert or not,that is right to prove the thing works. There are obviously many reasons why someone might not get the expected results, including impaired hearing, lack of listening experience, faults somewhere in the system, failure to follow instructions, etc. Thus, negative results mean precious little, except to support claims by naysayers that the device under test disobeys all known laws of science, is fraudulent, or is simply a placebo.

This makes it sound as though the intuition I was challenging in my last post was the intuition of BELIEVERS, when in fact I was challenging the intuition of SKEPTICS. It is remarkable, Geoff, that although my last post was in effect a DEFENSE of your views that cable directionality and fancy fuses might affect sound quality, you chose to treat it as an ATTACK of your views. No good deed...

Bryon

Almarg - Positive results don't mean anything to Skeptics, that much I agree with. Since it's probably true that anyone who hasn't tried one of these controversial devices, like aftermarket fuses, will be Skeptical of them - who wouldn't be? But for those who can hear the difference, who have tried them in their system, unde whatever test conditions they prefer, blind, double blind, A/B, whatever, then a Skeptic will have a difficult road to hoe trying to convince him that he didn't hear them. It's partly a question of how much you trust your hearing, how much experience you have listening, how developed your skills are listening.

B C - not sure why you use the word intuition, that appears to be your way of saying this whole thing is psychological. I am saying that at some point one has to trust his ears and saying, well, I'm not really sure what I heard. Even the manufacturer of Hi Fi Tuning fuses steadfastly refused, for many years, to believe fuses were directional, even his own. His theory was that fuses will eventually adjust to be "correct" no matter which direction they are inserted. About three years ago guess what? His fuses come out with those funny little arrows on them. He finally saw the light. You could say he was a reconstructed die hard Skeptic. By the way, fuse directionality is not difficult to prove, it's ridiculously easy. Any old fuse will do. Just reverse fuses one at a time and go with the direction that sounds best. Mystery solved.