Heavy gauge speaker wire versus ACD technology

BlueFox

Interestingly, while the OP claims a PhD in Physics, he does not realize, or acknowledge, his measurements are flawed. Speakers need to be measured in a vacuum in order to eliminate the distortion introduced by the random motion of air molecules.















:eek: :eek:

inspiredsports

BlueFox wrote: »

Interestingly, while the OP claims a PhD in Physics, he does not realize, or acknowledge, his measurements are flawed. Speakers need to be measured in a vacuum in order to eliminate the distortion introduced by the random motion of air molecules.

That's why I'd like to read what he's written.

I like to know just how smart people who claim to be so smart really are by reading for myself.

It's kind of a way I measure rather than accept their subjective self-opinion.

Jetmaker737

jcandy wrote: »

What other possibilities for converting an electrical signal to vibrations (transduction) and propagating those vibrations to the ear (acoustics) are there? Are you suggesting there is a mysterious "missing" phenomenon? If so, are the designers of your loudspeakers also missing out by sticking to the same "dogma" as me? I would claim that my approach is better described as "kosher" with regard to the actual process that engineers use to produce the loudspeakers you buy.

My point doesn't concern the design and implementation of speakers which is certainly the result of analytical and empirical science, but rather the modeling and measurement of the effects of the speakers, and the variables that affect speakers, on human beings. And the rather simplistic concept that by measuring SPL we have measured all there is to know about it.

Charlie Freak

dragon1952 wrote: »

It's a little condescending to me when these are brought up in a discussion like this. It seems that the measurement crowd is always trying to 'enlighten' the other side as if the reason for their 'misguided' beliefs are because of a lack of education. Heaven forbid many of them are educated people just like you that have formulated their own opinions through extensive experimentation and effort, and have thrown out any bias and preconception long ago.

I can understand too why it's insulting. But eliminating bias is not a simple matter. Many posters here pretend like bias/placebo don't even exist at all. "I know what i heard. 'nuff said, and if you don't believe me, screw off!" I think that is the thing that's so frustrating to the more objectively minded people.

It shouldn't be considered an insult for a person's claims to be questioned when they readily admit that they haven't made *any* effort whatsoever to eliminate bias/placebo. Even something as simple as asking a friend to switch the cables, in an informal blind test, while you try to guess which cable is which.

Personally, I welcome this type of scrutiny from others. Because it helps assure me that I didn't waste my money.

When a person reacts with outrage and anger at a suggestion that placebo/bias could have played a role, because their comparisons between cables were sighted tests.... well I think that says a lot about them, and very little about the cables. You can draw your own conclusions.

Hundreds of studies in various fields have shown over and over again that in sighted tests, people will claim to taste/hear/smell significant and extreme differences. But when the labels are hidden, they are unable to obtain test scores that are any better than flipping a coin. This cannot be denied. It's a fact. It doesn't mean they're lying, or stupid, or deaf. It just means they're human.

Any right-minded person applies this logic to everything in life, naturally, in order to separate fact from fiction. If another person makes a claim that seems to defy all known laws of the universe, it's normal for other humans to question how they came to that conclusion.

In the case of cables, all known ways of measuring show that there is little/no difference. All properly conducted blind listening tests confirm that the measurements appear to be correct. So this seems like a case where a person who says they hear a difference is making an extraordinary claim, and so the burden of evidence is on him.

The heckler posts that amount to "well, you're a poo-poo head troll who doesn't know ****" are nothing but personal attack, and personal attack is the hallmark of a lost argument.

jcandy

DSkip wrote: »

I also find it hard to beleive you can back up something as subjective as SQ with science. You might tell me Speaker A is better than Speaker B, but I might think its the other way around. Sound Quality, as I perceive it, is completely different than what my father perceives it as. He prefers his 80's Sansui speakers over the LSi7's, and I am the other way around. He likes the tonal qualities of the Sansui's, and I prefer the details and clarity of the LSi7's.

This test is not at all about sound quality (SQ), and says nothing about listener preference. Its only about measuring a difference between two states of the amp-loudspeaker system. I could just as well have used White Van speakers for this test.

In listener preference tests, we compare two often very different loudspeakers with very different SPL, and ask listeners which ones they prefer. Often, people prefer loudspeakers which are less accurate. Sometimes people prefer more distortion in the short term. So, I accept that such preferences exist. But that's not the issue in the present case.

ohskigod

this thread reads like War and Peace

painful

megasat16

FTGV wrote: »

Correct,and there are some that claim inherent superior damping properties for the yellow ones but IMO thats all bunk.

:biggrin::biggrin:

It appears that if the OP's measurement extended beyond 20k it might also reveal the break up mode to be near the same point as in Zaph's.Otherwise the two curves look very similar.From what I gather Vifa have a good record of consistancy from one sample to another.

I quite agree the later measurements are closer to that of Zaph measured graphs. But let's don't forget small variation in these plots shift quite a bit of frequencies.

I probably had put a little too high expectation on a affordable tweeter. I found the cost is $16 from PE.

megasat16

Prof. Jcandy

I do believe you hold a Ph.D in Physics. So, when will you start making a real contribution to better sound system or better understanding of what a good sound is?

DMara

I'm amazed at the amount of replies this thread got Come on, why did you guys keep coming back to it? There's plenty of other useful threads to take part in.

jcandy

megasat16 wrote: »

Prof. Jcandy

I do believe you hold a Ph.D in Physics. So, when will you start making a real contribution to better sound system or better understanding of what a good sound is?

Funny you should ask. I am working on two big audio projects now: one related to software, the other to theory/computation.

megasat16

jcandy wrote: »

Funny you should ask. I am working on two big audio projects now: one related to software, the other to theory/computation.

I am all ears! It's better than ongoing useless arguments that proves nothing.

Please do share if it's nothing to violate your pending patents or of commercial interest.

Any chance you familiar with writing a new DSP algorithm?

Really, anything that will help to reproduce music from Source to Speakers without adding or subtracting much (I know it's impossible that nothing is lost or added but how to minimize it) is my main interest in this Hobby.

megasat16

Oh wow. I just found you on the DIY Audio.

I've stumbled your Capacitor Thread before but I wasn't aware you were the thread starter.

http://www.diyaudio.com/forums/multi-way/173249-capacitor-audibility-fact-fiction.html

Please tell me objectively what your findings with regard to the above DIY Audio Thread?

I also have the same ID on DIY Audio.

halo71

Maybe he is still pissed about this one? Seems nobody took the bait over there.

http://www.diyaudio.com/forums/everything-else/173289-club-polk-cult.html

mrbigbluelight

It's important to note that I've been touching myself as I read through this entire thread.

YOU might not think it's important to note that but I have a pie chart that shows I'm right !

jcandy

halo71 wrote: »

Maybe he is still pissed about this one? Seems nobody took the bait over there.

http://www.diyaudio.com/forums/everything-else/173289-club-polk-cult.html

DIY audio is a very serious forum (although not without some lighter content). The people are also very technically minded, too, for whom nothing in my ACD technology demonstration would be controversial. I bet quite a few people there (including those who have written professional software) could have told me at once at what frequencies the soda can diffraction would be a maximum. So, that issue was just not on their radar.

On the other hand, when I first came to Club Polk with a set of dead SDA2Bs, I encountered some helpful people who pointed me in the right direction. Then, when I posted measurements, I came to meet the more disturbing members of "Cult Polk" with their aggressive "trust your ears" and "you need to be flushed, troll" mentality.

jcandy

DSkip wrote: »

My ? wasn't really about the test per-se, but more about your opinion. I really am interested in what you consider the biggest factors in SQ. This isn't meant as a "picking" question. I know from years of experience that SPL can change the perceived SQ through the tuning I have done in my car. I really don't know the importance you place SPL on overall SQ though. I'm trying to see your side of it, but I need some help.

Does the depth of the music depend on the frequencies that are being played, or is it something more?

This is a subject that is basically at the heart of audio design, easily the subject for a book. In a nutshell, I think its agreed that flat ANECHOIC (reflections eliminated) SPL is probably the single most important factor (studies have shown this) in determining subjective preference. Its pretty hard to make a "bad" speaker if you ensure the SPL is flat. On the other hand, what separates a good speaker from a great one are other factors like (1) nonlinear distortion, (2) power response/directivity and (3) power handling (speakers eventually fall apart as the volume increases).

DSkip wrote: »

If two speakers produce the same SPL graphs, should they sound identical?

First, remember that any given SPL curve is derived from a measurment at one place in space (say, on the tweeter axis at a distance of 1m).

So, given the use of modern low-distortion drivers, two speakers will sound the same on the measurement axis if the SPL is the same there AND if you listen in an anechoic chamber. That's obviously not a real-life situation! In real life, speakers with similar on-axis SPL may have very different off-axis behaviour, which will give rise to different types of reflections which color the sound.

Here's a different example: imagine two speakers have the same flat on-axis SPL and directivity, but one uses low HD/IMD drivers, and the other uses some lousy drivers. Its possible to build such a creature. These speakers will not sound the same as their low-distortion counterparts even though they generate the same SPL curve.

Good question that one.

inspiredsports

jcandy wrote: »

This is a subject that is basically at the heart of audio design, easily the subject for a book. In a nutshell, I think its agreed that flat ANECHOIC (reflections eliminated) SPL is probably the single most important factor (studies have shown this) in determining subjective preference. Its pretty hard to make a "bad" speaker if you ensure the SPL is flat. On the other hand, what separates a good speaker from a great one are other factors like (1) nonlinear distortion, (2) power response/directivity and (3) power handling (speakers eventually fall apart as the volume increases).


First, remember that any given SPL curve is derived from a measurment at one place in space (say, on the tweeter axis at a distance of 1m).

So, given the use of modern low-distortion drivers, two speakers will sound the same on the measurement axis if the SPL is the same there AND if you listen in an anechoic chamber. That's obviously not a real-life situation! In real life, speakers with similar on-axis SPL may have very different off-axis behaviour, which will give rise to different types of reflections which color the sound.

Here's a different example: imagine two speakers have the same flat on-axis SPL and directivity, but one uses low HD/IMD drivers, and the other uses some lousy drivers. Its possible to build such a creature. These speakers will not sound the same as their low-distortion counterparts even though they generate the same SPL curve.

Good question that one.

Yes, wasn't it?

Makes me wonder what those Zaphs sound like next to your uncles recently RDO'd (but not TL'd) 2B's.

I'm also wondering how much better the 2B's could have sounded if you hadn't scrimped on the high-pass caps, but I'm guessing you scrimped on the Zaph caps also.

It's very telling that in your own words, you write, "Its possible to build such a creature. These speakers will not sound the same as their low-distortion counterparts even though they generate the same SPL curve."

Hmmmm . . . .


Hmmmmmmmmmm . . . . . .

F1nut

jcandy wrote: »

DIY audio is a very serious forum (although not without some lighter content). The people are also very technically minded, too, for whom nothing in my ACD technology demonstration would be controversial. I bet quite a few people there (including those who have written professional software) could have told me at once at what frequencies the soda can diffraction would be a maximum. So, that issue was just not on their radar.

It wasn't on ours either.

jcandy wrote: »

On the other hand, when I first came to Club Polk with a set of dead SDA2Bs, I encountered some helpful people who pointed me in the right direction. Then, when I posted measurements, I came to meet the more disturbing members of "Cult Polk" with their aggressive "trust your ears" and "you need to be flushed, troll" mentality.

You mean the thread where you made the following comment about yourself.

jcandy wrote: »

Please forgive my skepticism, but unless I see an FR plot showing the difference I would be afraid do it. What does smooth and refined mean in terms of frequency response, power response, and directivity? Once I get the speakers working I desperately want to do some far-field FR measurements. This will establish a sort of baseline performance. Maybe the RDO-194 just needs some minor response shaping or attenuation, which may be possible by just adding a series and shunt resistor (L-pad).

Um, sorry if I am coming across as a bit of a jerk here.

And where another Polkie commented to you after a number of well intended folks tried in vain to help you......the same folks you are now calling, "the more disturbing members of "Cult Polk" with their aggressive "trust your ears" and "you need to be flushed, troll" mentality."

mmadden28 wrote: »

You came here asking for advice as to what to do next, then you rebut with engineering this and that. So be it if you want them to remain stock, no need to be demanding FR plots and all that from the people trying to help you out based on what their ears hear. Sheesh.

Looks like you're still the same jerk you were the first time 'round, which should make it obvious that it is not us, it is you.

nooshinjohn

F1nut wrote: »

Looks like you're still the same jerk you were the first time 'round, which should make it obvious that it is not us, it is you.

It's amazing that a guy can spend all that money on a Phd and still not be smart enough to just be a regular kind of guy. Kind of makes you wonder if he thinks he is better than us because of a fancy piece of recycled paper hanging on his wall or if he was a "jerk" before that as well.

nooshinjohn

DSkip wrote: »

What do you have against recycled paper?

Nothing at all... I think it's great that his degree came printed on the back of a Cracker-Jack box and that he put it to good use instead of sending it to a land-fill.

jcandy

inspiredsports wrote: »

Makes me wonder what those Zaphs sound like next to your uncles recently RDO'd (but not TL'd) 2B's.

Other than less bass extension (obviously), better in every respect.

inspiredsports wrote: »

I'm also wondering how much better the 2B's could have sounded if you hadn't scrimped on the high-pass caps, but I'm guessing you scrimped on the Zaph caps also.

Scrimped on what caps?

inspiredsports wrote: »

It's very telling that in your own words, you write, "Its possible to build such a creature. These speakers will not sound the same as their low-distortion counterparts even though they generate the same SPL curve."

Yes, what's your point?

Face

jcandy wrote: »

Other than less bass extension (obviously), better in every respect.

Soundstage? I think not.

jcandy

DSkip wrote: »

So, as long as SPL is the same at that given measurement point, it doesn't matter if the drivers are vertically or horizontally arrayed

That will change the directivity, an explained in point (2).

DSkip wrote: »

if the tweeter is a foot lower on one speaker than on the other,

With respect to the woofer?

DSkip wrote: »

There is so much more to music than just the tonality

You didn't read the post. When did I ever use the word "tonality"? Concentrate on what I say, not what your strawman says.

jcandy

Face wrote: »

Soundstage? I think not.

How would you know? Did you use your ears to come to that conclusion?

Face

Unless they were hooked up or set up incorrectly, based on Polk's reduction of the effects of interaural crosstalk alone, the 2B's should have a wider soundstage.

inspiredsports

jcandy wrote: »

. . . yes, what's your point?

My point is that Club Polk is most truly blessed to now have TWO true Genius speaker designers on board !! :rolleyes:

jcandy

Face wrote: »

Unless they were hooked up or set up incorrectly, based on Polk's reduction of the effects of interaural crosstalk alone, the 2B's should have a wider soundstage.

Of course they were set up correctly. In fact, I first set up these same speakers for my uncle in 1990. At the time, they were probably the best speakers I'd ever heard. My love for Polk started in about 1980, when as a kid in junior high school, I heard the monitor 10s in the local high-end hi-fi store. But is 2011 now and its possible to make a much better speaker using computer optimization, and incorporating the lessons learned since then. Is Polk, or anyone, still using the SDA crossover design?

I can give you one reason why you wouldn't want to: lobing. You get horrific lobing with the SDA effect, which leads to an unnatural sound. To my ears, in comparison to a really accurate speaker, the SDAs sound somewhat like they're playing in a well-damped hallway. That is largely due, IMO, to a major dip in the crossover region. IOW, I can hear the problem in the crossover.

jcandy

DSkip wrote: »

He looked at the SPL graph.


BTW, nice resume. General Atomics, eh? How did you like Texas?

I'll have to reserve judgement on the whole of Texas, but Austin was spectacular.

jcandy

inspiredsports wrote: »

My point is that Club Polk is most truly blessed to now have TWO true Genius speaker designers on board !! :rolleyes:

No really, please explain your point in more detail. I'm all ears.

tonyb

...and here I thought you were an educated man. Oh well....