A question for ex-cable believers

[E-Stat]

There's that river in China again...

FYI, "de" Nile is found in the land of the Pharaohs and the fertile crescent, Eqypt.

rw

[markw]

FYI, "de" Nile is found in the land of the Pharaohs and the fertile crescent, Eqypt.

rw

In the words of the immortal Homer Simpson, Doh!

[markw]

Amusing anecdotes aside, Mystic has a point regarding your test methodology. He's looking to test the test, as he's pointed out. Your test wouldn't be considered scientific, correct? Too many variables left unattended such as what Mystic mentioned.

On the other hand, it should be sufficient to satisfy you as the test taker (sorry, I have trouble using the term "testee") But let me ask... how many cables did you test? Two? Is it then possible that those two cables sound identical and that's all you "proved"? How is it then that you are able to extrapolate your test results to ALL cables and ALL people in ALL systems? I mean, if you want to view us with amusement, that's ok with me. But unless I'm missing a point or two of yours, I'm sorry but I'm chuckling myself! I think I see what Mystic is getting at. Sounds like that river flows in both directions!

... is to see if he can even identify them with accuracy under these oversimplified conditions. Should be a snap, right? What's there to prevent one's ears from discerning between the two cables except one's willingness to try? Excuses, excuses and more excuses...

And, I don't extrapolate this to "all" cables. I readily acknowledge that cables and interconnects can "sound" different but it's not in the technobabble, it's in scientific facts, and particularly in light of the tremendous disparity in cable pricing, and mostdecent tech doesn't cost a fortune.

I can't think of any other commodity where an item can be purchased for a few dollars and an item of similar functionality can cost upwards of 10, 100, 1000, and, in some cases I'm pretty sure in multiples of the tens of thousands. ... and where the debate rages over the actual differences where the rubber meets the road. If the differences warranted the price increases, do you thnk we would be wasting time going through this? I dount anyone will question the differences between a Hyundai and a Ferrari, although they will both get you to the store in pretty much equal time.

True, you may WANT the Rolex and that's all well and good, but please don't tell others that you bought it because it keeps better time than the Timex.

Obviously, there is more involved than the simple task of keeping time. ...likewise, this may well be an issue with cables and interconnects.

One other thing I've learned over the years is that when one introduces a new player into the game, one tends to listen more critically than before. And, in such case, one may have never noticed those "new, wonderful" sounds before.

But, now that one has become accustomed to listening for those "new, wonderful" sounds with the new toy, they may be plesantly surprised that when replacing the original item, they may well find they were there all along!

One just never bothered to listen for them before.

Yes, I WOULD suggest my simple* test for anyone who is "blown away" with their new cables. It's a nice way to actually see (or hear, to be more to the point) what one has bought.

*simple, as long as one has friends they can trust and a willingness to look honestly and deeply into the mirror.

[musicoverall]

[QUOTE=markw
I readily acknowledge that cables and interconnects can "sound" different .[/QUOTE]

Well, rat farts! You're no fun!

I was going to try your test but with my speaker cable vs a friends MIT whatzis for starters, mostly because they sound decidedly different. Whereas mine are transparent (whatever that means) his impart a definite sound. "Musical and non-fatiguing", he says. "Dull and rolled off", says I.

Now... my take on this phenomenon is that the MIT's are designed to take the glare off digital recordings i.e they are purposefully colored. So that's really not fair but, gosh awmighty, I was ready to show the world that speaker wire can and does sound different. So I need another suggestion for a comparison test. Five weeks from this saturday, I'll have the opportunity to start the test which can go unimpeded for 13 whole days! Perfect, since I can't always sit and listen to music every day... work and children interfere. What's your suggestion? I've sold my other cables already.

Also, as far as the improvement being warranted by the price, I acknowledge that the differences between a $500 cable and a $250 one aren't 100%. But for the person who wants to gain a 2% improvement for a 200% outlay - hey, if getting closer to the music is his ultimate goal, more power to him... uh, me! Furthermore, if someone could wave a magic wand and consistently shave 2 strokes off my golf game, I'd pay dearly. 2 strokes would be about the same improvement percentage. I've even tried Bedini Clarifying my irons! I still stink! Golf... Bah!

[markw]

... let's get the misquoting straight, OK? When people are accused of saying "all cables sound alike", what's meant, but rarely acknowledged by those hitting people over the head with that quote, is that several several caveats apply.

1) Similar construction. Some coax has better shielding. Some has none. Obviously, there may be some RFI.

2) Similar gauge and length. Most home users work in lengths of around 10' or less (ignote HT for now). A long length of a veeeerrrry thin cable may well sound difference than a short length of thicker cable.

3) And, like that MIT, some cables CAN be engineered to impart a distinct sound which, to me, seems like the antithesis of what's desirable but then, again, what do I know? In any case, what do a few resistors, condensers and inductots cost?

Keeping this in mine. knock yerself out. At least you'll really know what yer paying for.

[mystic]

... is to see if he can even identify them with accuracy under these oversimplified conditions. Should be a snap, right? What's there to prevent one's ears from discerning between the two cables except one's willingness to try? Excuses, excuses and more excuses...

And, I don't extrapolate this to "all" cables. I readily acknowledge that cables and interconnects can "sound" different but it's not in the technobabble, it's in scientific facts, and particularly in light of the tremendous disparity in cable pricing, and mostdecent tech doesn't cost a fortune.

I can't think of any other commodity where an item can be purchased for a few dollars and an item of similar functionality can cost upwards of 10, 100, 1000, and, in some cases I'm pretty sure in multiples of the tens of thousands. ... and where the debate rages over the actual differences where the rubber meets the road. If the differences warranted the price increases, do you thnk we would be wasting time going through this? I dount anyone will question the differences between a Hyundai and a Ferrari, although they will both get you to the store in pretty much equal time.

True, you may WANT the Rolex and that's all well and good, but please don't tell others that you bought it because it keeps better time than the Timex.

Obviously, there is more involved than the simple task of keeping time. ...likewise, this may well be an issue with cables and interconnects.

One other thing I've learned over the years is that when one introduces a new player into the game, one tends to listen more critically than before. And, in such case, one may have never noticed those "new, wonderful" sounds before.

But, now that one has become accustomed to listening for those "new, wonderful" sounds with the new toy, they may be plesantly surprised that when replacing the original item, they may well find they were there all along!

One just never bothered to listen for them before.

Yes, I WOULD suggest my simple* test for anyone who is "blown away" with their new cables. It's a nice way to actually see (or hear, to be more to the point) what one has bought.

*simple, as long as one has friends they can trust and a willingness to look honestly and deeply into the mirror.

[QUOTE=markw
One other thing I've learned over the years is that when one introduces a new player into the game, one tends to listen more critically than before. And, in such case, one may have never noticed those "new, wonderful" sounds before.

But, now that one has become accustomed to listening for those "new, wonderful" sounds with the new toy, they may be plesantly surprised that when replacing the original item, they may well find they were there all along!

One just never bothered to listen for them before.
[/QUOTE]


What you are saying seems reasonable, and may work that way for you, but I have found it usually works the other way for me. I hope for an improvement from the new component, but am underwhelmed by what I hear if I hear any difference at all. For me, the best indicator of a worthwhile improvement is removing the new item after several weeks of listening, and finding out whether I miss it and want it back in the system.

[RobotCzar]

[QUOTE=mystic] I can't find a complete study on line. I find results of tests, but you can't evaluate a result. A scientific study should provide a complete methodological description and present all the information and data needed for an evaluation. The TagMclaren study on two interconnects which used to be online was better documented than anything else I have seen so far. Do you know of others?[/QUOTE

You are very unlikely to find a test that meets your requirements. We only have less rigorous tests done by non-scientists (that I have heard about or seen).

I think you should consider the fact that no real scientist or peer-reviewed journal considers this an issue worth investigating. The silence is often rather stunning to new audiophiles. I suggest the reason for this lack of formal studies is that real scientists do not consider the topic interesting. In other words, they feel they already know the answer and a study would be a waste of time. (Recall that I have mentioned that theory and facts known about the limits of human perception indicated that people should not be able to hear differences in typical home audio cables.) Simply put, scientists think this is a moot issue (actually, they proably think it is dumb).

Now, scientists could be motivated to do such studies very easily---if someone gave them some money to do them. You should wonder why super-cable makers don't hire scientists to do such formal studies. After all, they could demostrate how much "better" their cables are, instead of writing "white papers" using techobable to "show" that their stuff works. Of course, no cable company (or amp company) has done this. I think I have a pretty good idea why. Do you?

[shokhead]

Maybe the company's that make the cable knows the truth from there research but once they saw how little or no difference there was,forgot to tell us.

[jneutron]

I think you should consider the fact that no real scientist or peer-reviewed journal considers this an issue worth investigating. The silence is often rather stunning to new audiophiles. I suggest the reason for this lack of formal studies is that real scientists do not consider the topic interesting.

From my recent experience....you would be incorrect in your suggestion.

Real scientists and researchers consider anyone who believes speaker cables can make a difference to be zealots, idiots, a-holes, and numbskulls...(z,i,a,ns)

So far, the majority of the ones I've contacted have dealt with me initially as being a member of the "zians" society. It takes a bit of back and forth, for them to realize I'm not a crank...

Do you know what the primary reason for their attitude??? Read any diatribe by JR..several of them pointed to his crap, saying..you believe this garbage??

It gets real tiring real fast, explaining a real scientifically based study to a real scientist or researcher, as a defense mechanism against being branded as residing within the same camp as JR..talk about your uphill battle..just getting them to listen is damn near impossible.

In other words, they feel they already know the answer and a study would be a waste of time. (Recall that I have mentioned that theory and facts known about the limits of human perception indicated that people should not be able to hear differences in typical home audio cables.) Simply put, scientists think this is a moot issue (actually, they proably think it is dumb).

Actually, they still do not understand how we localize..current models include a bandpass filter/rectifier/lowpass filter scenario. They also play with SAM and transposed SAM waveforms, but have not arrived to the point where they can develop a complete transfer function including ITD and IID variables.

Bottom line, they have not advanced to the point where they can model the development of a soundstage w/r to human hearing...so they do not know how to establish a real study.

Now, scientists could be motivated to do such studies very easily---if someone gave them some money to do them. You should wonder why super-cable makers don't hire scientists to do such formal studies. After all, they could demostrate how much "better" their cables are, instead of writing "white papers" using techobable to "show" that their stuff works. Of course, no cable company (or amp company) has done this.

Money would certainly motivate most. The cable makers do not because they are afraid the results will confirm the lack of difference touted by many...this is not to say there is no difference, just that the scientists have not progressed far enough to show such.

I was rather amazed at the current state of affairs in modelling human localization..not a very good one, IMHO, for the half century of work put into it..

Cheers, John

[RobotCzar]

Actually, they still do not understand how we localize..current models include a bandpass filter/rectifier/lowpass filter scenario. They also play with SAM and transposed SAM waveforms, but have not arrived to the point where they can develop a complete transfer function including ITD and IID variables.

Bottom line, they have not advanced to the point where they can model the development of a soundstage w/r to human hearing...so they do not know how to establish a real study.I was rather amazed at the current state of affairs in modelling human localization..not a very good one, IMHO, for the half century of work put into it..

Cheers, John

I agree with what you say about scientific reactions, I am trying to sound reasonable about the silliness so as not to turn off newcommers with open, if not yet entirely rational, minds.

I also agree that localization effects are the real issue in audio fidelity. Recording theory and techniques affect soundstage. Speaker response, placement, and room effects also affect soundstage and localization. To my ears, reality in 3D is THE factor that separates OK recordings from state of the art. Electronics, however, are not establshed as affecting sound stage, and I don't hear any real differences, like I do for the above factors.

Now, having said that let me be clear that one of the problems of current audio systems is the use of two channels to attempt to recreate (actually simulate would be a better word) audio 3D. That is a major problem, but I do not expect commercial multichannel audio to solve the "problem". Fact is, it has already been solved with ambisonics. Ambisonics calls into question your claim that scientists have not be able to specify a transfer function. They have, it just hasn't been implemented in the commercial market.

I suppose that you are too focused on electronics as that is your area of expertise. The issue has to do with acoustics and psychoacoustics, not electronic transfer functions. The basic issue is about acoustic transfer functions, electroncs is for encoding and amplification and are not an issue when distortion is low enough. Certainly, it is not clear that cable differences affect soundstage as that perception is due primarily do differences between the (usually 2) channels. If the same cable is used for all channels, then there can be little differences among the channels. For electronics in general, you should be concerned only with differences among channels as those are the only source of localization affects (if distortion is low enough).

Audio 3D simply isn't a quesiton of electronics. And, ambisonics has demonstrated the theoretical capability of reproducing a 3D sound field exactly (actually approaching exactly in the real world), which is exactly the transfer function we seek. Too bad audiophiles don't have the option to use ambisonics. It is also too bad that so-called audiophile don't attend to the real issues. The last two statements are probably related.

[jneutron]

Fact is, it has already been solved with ambisonics. Ambisonics calls into question your claim that scientists have not be able to specify a transfer function. They have, it just hasn't been implemented in the commercial market.

Hi RC..

Took a look at the ambisonics theory..interesting, but there appears to be a flaw..that would certainly explain the lack of embracing the technology has endured.

I explain....They use a set of mikes to ascertain the direction of the sound energy impinging on it in 3 dimensions...so, they can exactly duplicate the field at a point in space. Unfortunately, it will duplicate only that in a practical manner.. To duplicate the soundfield EXACTLY, requires time reversed technology, of the type found in this link:

http://focus.aps.org/story/v14/st24

If you examine this, you see that it is possible to focus the waves (sound, radio..same thing..) at a point in space..this article shows how they time reverse the signals. This is comparable to using a lens to focus light at a point, duplicating in essence, a point source of light...

But, application of this to acoustics poses a different problem..I can easily show how time reversed app will generate a virtual acoustic point source in space...which then expands EXACTLY as if the source were there...unfortunately, prior to the soundfield getting to that point, it has to go by the listener (assuming 360^O) of transducers. Meaning, ya can't get theyah from heyah...

They are approaching it incorrectly..

I am, however, thoroughly impressed with their writeup on the site...they are very, very, good at understanding the nature of localization..I fear they just got lost in the equations, and lost the sense of "feeling" or understanding..Look at this verbage....incredibly good..

In what ways is G-format actually superior to conventional 5.1 surround? To answer that question we need to consider briefly the shortcomings of conventional approaches. Conventional surround (and stereo!) recordings localize sound sources simply by means of level. To place something mid-way between front and rear left, for example, you simply apply equal levels to these two loudspeakers. This is not very satisfactory, however, for several reasons. Human hearing relies on different combinations of level, phase and arrival time -- as well as other factors -- to localize sound sources, and not solely on level. Loudspeakers in a conventional stereo pair are generally placed 60 degrees apart with respect to the listener. In this configuration, the ears can hear sound coming from both speakers and differences in level are interpreted as phase differences and provide localization information. This effect begins to fail as the speakers are moved further apart, and by the time you get to a 90 degree front stage -- as was found in quad setups and is still recommended in some quarters today -- a significant "hole in the middle" has developed (it's one reason for the center front channel in 5.1).
Level-only localization is poor at best in the rear, and virtually nonexistent at the sides. As a result, conventional surround tends to suffer from poor inter-speaker imaging. Sounds are sucked into the speakers and it is hard to get them to appear from anywhere else -- as a result, some engineers and producers have taken to deliberately placing sounds only in the loudspeakers: a simple and effective way out, but one that is rather limiting in creative terms. Another problem is the fact that as only level is involved, moving about within the listening environment changes the positions of sounds in the replayed image. Move to the left and you hear more of the left speakers, so the balance appears to move to the left. Move to the rear and the image moves backwards. This is not satisfactory: not only is the image unstable, it is only "right" in a very small spot in the center of the array -- the "sweet spot".

I suppose that you are too focused on electronics as that is your area of expertise. The issue has to do with acoustics and psychoacoustics, not electronic transfer functions. The basic issue is about acoustic transfer functions, electroncs is for encoding and amplification and are not an issue when distortion is low enough.

You are very incorrect....you have assumed that I CAN focus....silly you....:-)

When I say transfer function, I mean the function to be applied to the music signal left and right, to force the signal to image at a specific angular distance off axis, and at a specific depth from the listener..as such, it is an acoustic to electronic to acoustic transfer function, somewhat more complex than a simple pan pot...

It is also too bad that so-called audiophile don't attend to the real issues.

Many are told exactly what to attend to..by guru's..complete with garbage pseudo-science and made up crap...the audiophiles have no-one else to listen to, so they listen to the only voice there...

Cheers, John

[RobotCzar]

Of interest is a letter from Professor Stanley Lip****z in issue 24 of The Audio Critic:

"There is a common misunderstanding of sound immaging, perpetuated in Daniel Sweeney's article "Twice Shy: On Reencountering Multichannel Music Formats" in Issue No. 23, which I would like to address. Sweeny bemoans the presence of "interaural crosstalk" in surround sound systems in general and Ambisonics in particular, as if there is something inherently wroing about each ear hearing all the loudspeakers. This fallacy can be traced right back to a common belief that one of the defects of stereo reproduction is each ear hears both loudspeakers, and that the ideal would be that the left channel signal be heard only by the left ear. Such a situation would represent binaural reproduction and would require a binaural ("dummy head") recording as the source. But Sweeney is not discussing binarual sound, and both stereo and Ambisonics are predicated o the existence of this crosstalk.

Ambisonics goes further than stereo in that what it does (to the first order) is to sample the acoustic field in such a way that the combination of the signals from all the loudspeakers in the array produces, in the region of space around the center of the array, a reconstruction of the original acoustic wave field (both traveling and standing- wave components). If a listener puts his or her head in this sound field, then, because the wave fronts are similar to the original, the perception of directionality and space should correspond to the original too. It is a "wave front reconstruction" scheme in the small. The ear signals (crosstalk and all) will be correct if reconstructed wave fronts are correct. This is just like natural hearing. Increasing number of loudspeakers in Ambisonics (each fed its correctly decoded signal) increases the accuracy of the reconstruction and ther region over which it holds up. The interaural arrival time differencesw also correspond to natural hearing in Ambisonics.

All these aspects are correctly captured to the first order by Ambisonics...."

There are a couple of points I want to make about Lip****z's comments. First, note that "interaural crosstalk" is another "made up" issue in the high end. Note also that Bob Carver based a product line on it, but that does mean he is right. Therefore, what designers and manufacturers say and do is not some kind of proof of validity.

Second, note that he uses the phase "to the first order" which seems to be your sticking point (it is not exact). However, let's face two facts: we are not even getting first order spatial reproduction from classic stereo systems (or 5.1 multichannel) AND we are never going to get perfection. Perfection may not be required, as our sensory does not have infinite resolution. Just as we can't hear very small amounts of distortion, we may not be able to audio-locate beyond first order reproduction.

In any case, high end audio guys are twiddling their capacitors in search of better "resolution" when their whole set up (classic stereo) is an order of magnitude away from anything acceptable in regard to spatial reproduction. They keep thinking that if they pay mor money for electronics they will improve something that is ingrained in the recording and playback systems. This also helps us understand vinyl nuts because LPs impart an additional (and false) sense of space on playback. They may be right to the point that they are getting a "better" (if inaccurate) spatial illusion.

[jneutron]

There are a couple of points I want to make about Lip****z's comments. First, note that "interaural crosstalk" is another "made up" issue in the high end. Note also that Bob Carver based a product line on it, but that does mean he is right. Therefore, what designers and manufacturers say and do is not some kind of proof of validity.

Second, note that he uses the phase "to the first order" which seems to be your sticking point (it is not exact). However, let's face two facts: we are not even getting first order spatial reproduction from classic stereo systems (or 5.1 multichannel) AND we are never going to get perfection. Perfection may not be required, as our sensory does not have infinite resolution. Just as we can't hear very small amounts of distortion, we may not be able to audio-locate beyond first order reproduction.

Inter-aural crosstalk is a reality...it happens..I have been referring to it's effect as "sidebands". A true mono signal will visualize as a single point source, while the mind ignores the crosstalk...hence, to the first order, I agree in that the crosstalk can be ignored.

My sticking point is not the lack of exactness past "to the first order". My point is, the further the image gets from the array of drivers, the less the soundfield correlates to the correct waveform reconstruction..as well, smaller wavelengths have another issue..driver spacing affects the useability of phased array technology, hence will also provide ambisonic technology limitations..

It would be better to fully understand how the Bose system uses time and location based ITD divergence to produce it's huge soundstage image. That would certainly help the ambisonics, and is definitely applicable to binaural reproduction..but, I have seen nothing presented at the level of computational power required to do so..I do not even know if the Bose people understand how it does what it does..

They may be right to the point that they are getting a "better" (if inaccurate) spatial illusion.

Yes, we certainly agree on quite a bit...this included.

Cheers, John

[Toga]

Hiya RobotCzar!

You dismiss binaural recordings? Have you heard good ones? Discussions I've read point out the primary limitations of headphone listening as being in the suspension of disbelief only as long as you DON'T TURN YOUR HEAD. Bob Carver has come up with some doozies in his day, but he was right on the money with the Sonic Hologram Generator. The trouble with it was, it was built with ho-hum components available in the early eighties, and made too many one-size-fits-all assumptions. On recordings made with a coincident pair of microphones in a live acoustical space, the imaging is nothing short of breath taking. Room sounds, although detracting from the literal performance, restore the suspension of disbelief because one is not transported from aural effects one is localized within. Try sitting in an anechoic chamber. It will drive you nuts very quickly.

I didn't see anything mentioned in the Ambisonics blurb about Dynamic Comb Filtering (and OTHER factors?). This is the variable EQ curve generated by the shape of the head, positioning of the ears, and the outer ear shape itself, allowing placement of sounds that are moving from the front, overhead, and behind the head, because of the convoluting transfer function in real time. No gross level differences, no phase or time arrival cues, and yet you can "HEAR" in more than just a horizontal plane of a sound field. This research was being done at MIT and KEF starting in the '70s.

Simply because we are only gradually reaching for an understanding of ear/brain function is not sufficient justification for junk science to fill the void. Much like classical understanding of field theory being all wrong, and TDS measuring devices being inadequate for transmission line analysis for large signal effects at AUDIO frequencies, the trouble with being at the forefront of any field is that people ridicule you whether you are right or not.

I wish a Chinese Philosopher had asked a question: If one can taste the presence of a grain of salt on the tongue or not, could he also taste that same grain of salt added to the OCEAN?

[jneutron]

Much like classical understanding of field theory being all wrong, and TDS measuring devices being inadequate for transmission line analysis for large signal effects at AUDIO frequencies, the trouble with being at the forefront of any field is that people ridicule you whether you are right or not.

Would you please elaborate on those?

Several of my aquaintences at work would be very interested in knowing that they are all wrong..

Cheers, John

[RobotCzar]

Hiya RobotCzar!

You dismiss binaural recordings? Have you heard good ones? Discussions I've read point out the primary limitations of headphone listening as being in the suspension of disbelief only as long as you DON'T TURN YOUR HEAD. Bob Carver has come up with some doozies in his day, but he was right on the money with the Sonic Hologram Generator. The trouble with it was, it was built with ho-hum components available in the early eighties, and made too many one-size-fits-all assumptions. On recordings made with a coincident pair of microphones in a live acoustical space, the imaging is nothing short of breath taking. Room sounds, although detracting from the literal performance, restore the suspension of disbelief because one is not transported from aural effects one is localized within. Try sitting in an anechoic chamber. It will drive you nuts very quickly.

I didn't see anything mentioned in the Ambisonics blurb about Dynamic Comb Filtering (and OTHER factors?). This is the variable EQ curve generated by the shape of the head, positioning of the ears, and the outer ear shape itself, allowing placement of sounds that are moving from the front, overhead, and behind the head, because of the convoluting transfer function in real time. No gross level differences, no phase or time arrival cues, and yet you can "HEAR" in more than just a horizontal plane of a sound field. This research was being done at MIT and KEF starting in the '70s.

Simply because we are only gradually reaching for an understanding of ear/brain function is not sufficient justification for junk science to fill the void. Much like classical understanding of field theory being all wrong, and TDS measuring devices being inadequate for transmission line analysis for large signal effects at AUDIO frequencies, the trouble with being at the forefront of any field is that people ridicule you whether you are right or not.

I wish a Chinese Philosopher had asked a question: If one can taste the presence of a grain of salt on the tongue or not, could he also taste that same grain of salt added to the OCEAN?

Let's consider Toga's comments from a crtiical thinking point of view.

1, At no point did I (or the writer I was quoting) dismiss binaural recordings. Simply read what is written in the post, Lip****z says that playback without interaural crosstalk is binaural. Binaural recodings can be quite realistic simply because listening room acoustics are eliminated AND recording room acoustics are nearly perfectly perserved. Unfortunately, the not-moving-your-head problem turns out to be rather serious. We get a lot of location cues by moving our head about to gather more data by changing the perspective of our ears in regard to the audio source. You can't do that with headphones and a binaural recording. The critical thinking point is that Toga simply reacted to what he wanted to hear or thought he heard instead of what was said by the writer. The writer's point is that "interaural crosstalk" from speaker arrays is not harmful.

2. He claims Carver was right, but offers no evidence or even and argument as to why he is right. The author I quoted is a distinguished professor of electronics used for audio reproduction, I know that doesn't match the celeb status of Bob Carver, but the truth is, Bob Carver never offered an explanation as to why interaural crosstalk is bad. He simply assumed it is. Sorry--don't buy it unless you back it up with some evidence or at least a logical argument. I'm not taking Bob Carver's word on it (though I might take Lip****z's word on it).

3. "it was built with ho-hum components", here again, Toga leaves the realm of critical thinking. Do ho-hum components lead to ho-hum performance? Seems logical based on good ole' common sense, but it is based on several fallacies. We can simply measure performance and see that many factor affect performance other than ho-hum components and that most components do the job well enough ho-hum or not--electrical performance can be calculated, including the expected performance range. The belief that "quality" components always result in audible differences is a sure sign of highenditis.

4. References to "junk science" is merely name calling. Where in Toga's statement's is evidence presented or a logical argument made? He does offer up a technobabble example of the "failure" of junk science in the past. "Much like classical understanding of field theory being all wrong." This statement marks Toga as a scientific neophyte, in no way is classical field theory "all wrong", it has served us well for a century, such theories are viewed as "incomplete" in light of new information. The equations that Maxwell used to establish electromagnetic theory are perfectly correct in our everyday experience and only break down under very extreme conditions that we on Earth never encounter.

5. If one could (via ambisonics or binarual) reproduce the original sound field (or a reasonable facsimile) then comb filtering is a moot point. No combfiltering occured within the area of "reasonable sound field reproduction" (by definition) AND the comb filtering due to your ears would be the same as for the actual live event that was recorded. When it comes to whether comb filtering is an issue with Ambisonics, I'll go with Lip****z's opinion over Toga's.

6. "the trouble with being at the forefront of any field is that people ridicule you whether you are right or not. " Assuming for a moment that it is not Toga that is at the forefront of the field, we come to a major point of science. People deserve "ridicule" if they cannot properly support their claims via standard scientific method. Most of us have no way a knowing if the fool at the forefont is right or wrong, but scientific method is specifically designed to weed out the pretenders. I think I'll be sticking with scientific method over pundits and crackpots at the forefont. If you have a major new scientific insight, go for your Nobel prize, but don't think sounding arrogant and dropping tehcnobabble is going to really cut it.

[Toga]

Meester Neutron,

I did not make that claim myself...

Haha, I was paraphrasing YOU when you pointed out ideal field theory in textbooks differed in the real case, which I would agree with, but not at audio frequencies. I would also argue that -0.5dB @ 20kHz is a measurable difference, but not an audible one for most people, seeing as how they can't hear such frequencies reliably played back at ANY level.

It is my professional assertion that science as a body moves more slowly than its most daring practitioners. It was your claims about hollow core wiring that is at odds with common sense and industrial practice for high power low frequency transmission.

[Toga]

Woah, woah, waoh!

I see I touched more than a nerve. Your post was amazingly defensive of propriety. Point by point:

1, At no point did I (or the writer I was quoting) dismiss binaural recordings. Simply read what is written in the post, Lip****z says that playback without interaural crosstalk is binaural. Binaural recodings can be quite realistic simply because listening room acoustics are eliminated AND recording room acoustics are nearly perfectly perserved. Unfortunately, the not-moving-your-head problem turns out to be rather serious. We get a lot of location cues by moving our head about to gather more data by changing the perspective of our ears in regard to the audio source. You can't do that with headphones and a binaural recording. The critical thinking point is that Toga simply reacted to what he wanted to hear or thought he heard instead of what was said by the writer. The writer's point is that "interaural crosstalk" from speaker arrays is not harmful.

1. Stereo has some pitfalls in its interceptive nature of capturing sound pressure and redistributing them again. As I stated in my post, certain recording pickup arrangements lend themselves to image recovery more than others. YOU appeared dismissive of interaural crosstalk by calling it a "made up issue". This is in direct relation to Binaural recording, since crosstalk would be detrimental in reproducing similar recordings with a regular 60 degree stereo pair of speakers.

2. He claims Carver was right, but offers no evidence or even and argument as to why he is right. The author I quoted is a distinguished professor of electronics used for audio reproduction, I know that doesn't match the celeb status of Bob Carver, but the truth is, Bob Carver never offered an explanation as to why interaural crosstalk is bad. He simply assumed it is. Sorry--don't buy it unless you back it up with some evidence or at least a logical argument. I'm not taking Bob Carver's word on it (though I might take Lip****z's word on it).

2. Carver published a manual in the form of a white paper regarding Sonic Holography, describing the recovery process, and the reasons why receiving wrong channel information interferes with the ear brain ambience recovery process. You may have heard of Polk's SDA, and other less famous realizations of interaural crosstalk cancellation. The imaging qualities of planars toed in "just so" have a natural channel to channel decrease of crosstalk as well. Critical thinking does not go hand in hand with pedigree fawning; "He's professor so and so".

3. "it was built with ho-hum components", here again, Toga leaves the realm of critical thinking. Do ho-hum components lead to ho-hum performance? Seems logical based on good ole' common sense, but it is based on several fallacies. We can simply measure performance and see that many factor affect performance other than ho-hum components and that most components do the job well enough ho-hum or not--electrical performance can be calculated, including the expected performance range. The belief that "quality" components always result in audible differences is a sure sign of highenditis.

3. The ho-hum components I was referring to are JRC 4558 and LM324 or TLO74 Op Amps. Their noise floor is not selected as in the NE5532D, so there are some signal insertion problems with the processing that could have been avoided using higher grade components. Modern offerings from Analog Devices or TI's Burr Brown line could make improvements that would raise the bar for the Sonic Hologram process. The processor was often inserted between a pre-amp and power amp, where its noise floor could be distracting during quiet passages. I'll let your brutish derision on this speak for itself...

4. References to "junk science" is merely name calling. Where in Toga's statement's is evidence presented or a logical argument made? He does offer up a technobabble example of the "failure" of junk science in the past. "Much like classical understanding of field theory being all wrong." This statement marks Toga as a scientific neophyte, in no way is classical field theory "all wrong", it has served us well for a century, such theories are viewed as "incomplete" in light of new information. The equations that Maxwell used to establish electromagnetic theory are perfectly correct in our everyday experience and only break down under very extreme conditions that we on Earth never encounter.

4. In this portion of your criticism, I was paraphrasing jneutron when he threw out textbook understanding of field theory. Talk about an unsupported thesis. TECHNOLOGY based on bad science rarely works as advertised. I admit I was mocking a little bit when I referred to those claims he made earlier, and did not properly point out the source of the claims.

5. If one could (via ambisonics or binarual) reproduce the original sound field (or a reasonable facsimile) then comb filtering is a moot point. No combfiltering occured within the area of "reasonable sound field reproduction" (by definition) AND the comb filtering due to your ears would be the same as for the actual live event that was recorded. When it comes to whether comb filtering is an issue with Ambisonics, I'll go with Lip****z's opinion over Toga's.

5. The comb filtering I was referring to, and that you may not be aware of, is from the multiple path lengths that sound follows over the human head, and its myriad diffraction patterns that vary based on angle of sound incidence. It is the one thing about Ambisonics I have seen in their early implementations I agreed with; a vertically oriented speaker pointing downward. At the time it was competing with other 4 quadrant sound schemes.

6. "the trouble with being at the forefront of any field is that people ridicule you whether you are right or not. " Assuming for a moment that it is not Toga that is at the forefront of the field, we come to a major point of science. People deserve "ridicule" if they cannot properly support their claims via standard scientific method. Most of us have no way a knowing if the fool at the forefont is right or wrong, but scientific method is specifically designed to weed out the pretenders. I think I'll be sticking with scientific method over pundits and crackpots at the forefont. If you have a major new scientific insight, go for your Nobel prize, but don't think sounding arrogant and dropping tehcnobabble is going to really cut it.

6. Again directed at the trailblazing efforts jneutron takes credit for in his work, I was commiserating that right or wrong, it is easy to get caught up in the POLITICS of science, that has less to do with the scientific method and more about ass covering and career management. Many good ideas have taken centuries to take hold against the status quo.

In short, I'm guilty of a lazy post. I switched my voice to several audience members without addressing them directly, and thus muddled the message I was trying to send. At no point was I referring to any of my own thoughts, ideas, or position in the industry. I simply disagreed with your excitement over Ambisonics having any sort of handle delivering multiple sources at a point in space when your speakers are not at the point the microphones were. Sadly people forget the point of audio is presenting a convincing ILLUSION rather than some actual clairaudience; the Binaural process comes closest in the horizontal plane, and Carver et. al. was onto something that you haven't seemed to take the time to investigate. Thanks for the opportunity to clear it up.

Your fierce approach to my post ambiguities make me wonder however... Critical thinking flaws? Can you read your post and spot some?

[jneutron]

I was paraphrasing YOU when you pointed out ideal field theory in textbooks differed in the real case, which I would agree with, but not at audio frequencies. I would also argue that -0.5dB @ 20kHz is a measurable difference, but not an audible one for most people, seeing as how they can't hear such frequencies reliably played back at ANY level.

It is my professional assertion that science as a body moves more slowly than its most daring practitioners.

Hmmm..I'm trying to figure out exactly where you received the wrong impression..

I have not stated that classical field theory is incorrect. What I have stated, is that the TEXTBOOKS are incorrect if they assert the old exp model for low freq..but, some of them clearly point out the limitations of the model...you musta missed it..

What I have pointed out, is that to use the standard skin depth approximation, which is that exponential, TEM based isotropic propagation model for cases where there is significant current penetration, is incorrect.

In point of fact, it can easily be shown how incorrect that approximation is, by solving the Bessel equations for the conductor current transport...so, I actually USE classical E/M theory to prove that what you and others consider as "skin theory" is indeed, incorrect.

(I must confess, that I haven't figured out from your posts, if you even understand the subject at all..but, that is only from what you have said so far..)

The fastest way to show this is by excerpt.....from an AH article..here's the link..

http://www.audioholics.com/techtips/...skineffect.php

This material appears in my new book, High-Speed Signal Propagation: More Black Magic. The book is available now through www.barnesandnoble.com . The first shipments should arrive from the printer in March.

The models in this book show how to derive both magnitude and phase for the skin effect resistance, and how to convert that into an overall model for signal propagation. The book provides several choices of models for the transition between the DC conduction (where the current fully penetrates the conductor) and skin-effect conduction (where the current is restricted to a shallow band just underneath the perimeter of the conductor).

OF NOTE, is the statement "several choices of models for the transition "...note that he is acknowledging the distinction between high penetration of current, and shallow...

I have been stating, and re-stating....THE USE OF THE NORMAL ISOTROPIC PROPAGATION of a signal at right angles to the conductor surface, is incorrect...it is the high frequency shallow penetration model, INACCURATELY used to characterize an entirely different scenario..

It was your claims about hollow core wiring that is at odds with common sense and industrial practice for high power low frequency transmission

I have absolutely no idea what "claims" I've made that are at odds with common sense or industrial practices. I did point out the fact that the power companies stopped using solid copper when the diameter of the copper exceeded 4 inches, as the current density in the center of conductors larger than that does not justify the added weight. Here at work, we just naturally use flat copper plates when we get into the 20 to 30 Kiloamp range, but that is more for the accessibility and working of 1 and 2 inch thick copper plate. And for long, 10 kiloamp runs, we will indeed use hollow copper, water cooled pipes. Copper, after all, is quite expensive.

I do know that you do not seem to understand what I've been saying. Instead of jumping on my case with statements such as "I was paraphrasing jneutron when he threw out textbook understanding of field theory, and "Talk about an unsupported thesis". you should be asking questions..what I've been talking about eludes most..you are jumping the gun, and by doing so, are not demonstrating an adequate understanding of e/m field theory

TECHNOLOGY based on bad science rarely works as advertised.

I would say it never does..

I admit I was mocking a little bit when I referred to those claims he made earlier, and did not properly point out the source of the claims

And I will admit that I have so far, put up with your mocking attitude, without calling your lack of understanding to the table..

If you have any actual technical questions, I am always ready to talk shop..If your sole purpose is to mock and criticize me simply because you do not understand the field theory correctly, then at least you have identified both your attitude, and your level of expertise in the subject..

My understanding of this subject exceeds the bounds of your experience, as well as most of the writers you will be able to direct me to in your attempts at proving me incorrect (which I may add, is just fine..that is part of discussion of differences of opinion), and I must add, that there's NINE gentlemen within 100 feet of me, who make my understanding of this topic, shall we say...weak, insignificant, pale in comparison?? (talk about working in a humbling environment.) So if you actually show me something I don't understand, all it takes is a short walk...lord knows, I can use the exercise...:-).

Your last link, the author didn't calculate a trivially simple inductance problem correctly...off by a factor of 15??? What's up with that? Didn't you read the link first?

I prefer reasonable civil dialogue...I hope that is why you are here..

Now..in the hopes that you are hear to discuss civilly...a picture..this is an old one, I can't recall the source..
It is a comparison between the exponential model you seem to believe, as well as everyone else, vs the exact solution for current density within a conductor..

Note how badly the exponential matches? The TEM model does not work over the audio band..unfortunately, it is the easiest to understand and use...

And, that is only at one current level..penetration depth, or better stated, exclusion of current from within, is entirely based on the eddy currents opposing the current...so, penetration depends on the absolute rate of change of current, as that is what generates the internal eddy currents...

What was the current level in this example? Who knows...but, the exponential model doesn't require the current be known, as it by nature, defines the current as a result of the characteristic impedance of copper, while the exact solution has the current as a variable, just like regular wire..Oh, also wanted to mention...the exp. model is the one Hawksford used, so he of course received incorrect results..his model, as does yours, expresses the TEM wave going into the copper as the orthogonal components of the circumferential magnetic field lines and the voltage gradient along the axis of the wire, with the radial direction of prop....Unfortunately, the voltage drop along the axis is a direct sum of the resistive drop and the inductive drop during current slew (you know, the storing of inductive energy). But, I fear I'm injecting too much detail, as first you must learn the limitations of the model you have hung your hat on..Once you understand, then we can get down to some cool discussion..I hate limiting the technical stuff to such a rudimentary level.

I've also learned to plant only one picture per post...it helps to see it and the dialogue..

Cheers, John

PS...please read the posts more carefully. If you do not understand, just ask..

[Toga]

"My understanding of this subject exceeds the bounds of your experience, as well as most of the writers you will be able to direct me to in your attempts at proving me incorrect"

It is for this reason ONLY I mock you jneutron. Many of your posts present this Elitist flavor of thinking, and while I applaud the scaling of your expertise in relation to your mentors or colleagues, you are skating on thin ice in the face of a vast proportion of the ACTUAL ENGINEERS AND TECHNICAL PRACTITIONERS of the Audio Industry. So I too can "walk a few feet" and speak with the designers of amplifiers, loudspeaker drivers, electrical components, and systems used by literally MILLIONS of people all over the world and they LAUGH at viewpoints and models that are used to exaggerate the audible effects of typically utilized wire.

In your own post you mention using flat conductors as one of my original posts mentioned, because they are far more practical to manufacture than cylinders. I have no doubt by the time you scale up conductors to over 4", "wasted copper" begins to justify specialized manufacturing (tube bending).

The posts I am trying to show you are where real guys with real test gear that do this all day every day in AUDIO have made MEASUREMENTS that comfortably downplay fear mongering regarding actual skin effect on transmission of upper octave frequencies at audio-scaled power levels, also assuming things like around 10M of cable max, 4 to 8 ohm loads, etc.

You can't hide the truth behind equation juggling. Check out these links for more MEASUREMENTS on signal loss in these typical scenarios. If your non-TEM theory does not predict the losses as they are measured, then it is misapplied. I'll believe Belden's math until measurements disprove it.

http://www.audioholics.com/techtips/...udiocables.php
“Actual measured increase in AC Resistance due to Skin Effect at 20 kHz is less than 3%. See the results in our Cable Face Off Article for more details.”
http://www.audioholics.com/techtips/...diocables2.php
http://www.audioholics.com/techtips/...diocables3.php

http://bwcecom.belden.com/college/techpprs/tpsemird.htm




It occurs to me that rather than out of ignorance, current scalar terms are left out of the skin effect equation precisely because at the magnitudes in audio applications they aren't relevant. The original decision to leave the terms out may not be as obvious to practitioners, some of whom may ignore them out of lack of awareness. You have repeatedly made references to extremely high current applications where eddy current losses become significant. For a typical listening test done perhaps around 90dB with 110dB signal peaks, the average RMS currents at any frequency in a speaker cable would be around 350mA, given a 90dB efficiency loudspeaker system driven at 1W RMS AVG @ 8Ohms. My suspicion is that your graph above elevates the missing terms into BECOMING important at "20KA - 30KA". This is precisely why actual audio measurements of signal strength at high frequencies at the speaker terminals do not show the effects you describe.

[jneutron]

It is for this reason ONLY I mock you jneutron. Many of your posts present this Elitist flavor of thinking, and while I applaud the scaling of your expertise in relation to your mentors or colleagues, you are skating on thin ice in the face of a vast proportion of the ACTUAL ENGINEERS AND TECHNICAL PRACTITIONERS of the Audio Industry. So I too can "walk a few feet" and speak with the designers of amplifiers, loudspeaker drivers, electrical components, and systems used by literally MILLIONS of people all over the world and they LAUGH at viewpoints and models that are used to exaggerate the audible effects of typically utilized wire.

From the length of your posts, especially the one word or two ones, it is not possible to figure out what you are saying..at least, these newer, longer ones have some meaning..

At least now I see where you are getting your information..AH....geeze, go figure.

Before you attempt to impress me with links to AH articles, do me a big favor.....Ask Gene D (you know, the owner of AH) who the people are who he asks to proof his more technical writeups...yah, you guessed it...he occasionally quotes me, and continues to beat on me to write some articles for him, covering the exact stuff I'm explaining to you.. Sorry you were unaware that I do that, as I do not use my name as a forum moniker, but I certainly am aware of all the AH stuff..having had a hand in some of the more technical ones. It is a shame we live in a world where one has to live behind a moniker..

This "elitist" flavor, which you take great pride in noticing, is a direct result of you blatently mocking what you don't understand..this I state, because at the end of your post, you again present the incorrect skin equation...and I tire of your increasingly arrogant flavor, hence the explanation that you know very little..tempered by the statement that I am certainly not the top of the food chain either, I work with them..

If you read the Belden writeup you pointed to, you should realize that they are still talking about propagation normal to the surface of the copper foil....not the effect of current redistribution...

Hey, if you still don't believe me, go ask Gene D...he will forward your questions to me..I'm saving you the middle man..

In your own post you mention using flat conductors as one of my original posts mentioned, because they are far more practical to manufacture than cylinders. I have no doubt by the time you scale up conductors to over 4", "wasted copper" begins to justify specialized manufacturing (tube bending).

That, and a crane to pick the stuff up.

The posts I am trying to show you are where real guys with real test gear that do this all day every day in AUDIO have made MEASUREMENTS that comfortably downplay fear mongering regarding actual skin effect on transmission of upper octave frequencies at audio-scaled power levels, also assuming things like around 10M of cable max, 4 to 8 ohm loads, etc.

The point I am making, is that if you are trying to point me towards my own quotes to support your argument that I am incorrect....that doesn't work.

You can't hide the truth behind equation juggling. Check out these links for more MEASUREMENTS on signal loss in these typical scenarios. If your non-TEM theory does not predict the losses as they are measured, then it is misapplied. I'll believe Belden's math until measurements disprove it.

You still do not understand...Belden's math in that particular instance, is correct..but that is the skin equation for TEM propagation normal to the surface...and does not apply to what I am talking about..

I fear that I am going to have to bow to Gene's request, to write those articles explaining all this stuff, as I have never been put into the situation where someone like you is trying to prove me incorrect by using articles I either co-wrote, proofed, or contributed to...a weird scenario at the least..

Perhaps if you see what I have posted here, on AH, then it will be...more credible??

Oh, and btw...I do not exaggerate. I will formulate, I will hypothesize, I will design, I will test, I will present...but I do not exaggerate.

Cheers, John

[Toga]

LOL jneutron, that is a funny situation.

However, I am still trying to reconcile your model claims, with measurements that you seem to be denying. Please tell all of us cable interested people, HOW MUCH SIGNAL LOSS WE SHOULD EXPECT BASED ON YOUR ASSUMPTIONS at 10KHz, 20KHz, using 10m of regular 12ga. speaker cable. Then, using your predictions, we can compare to measurements already made using differential display techniques. I have a stack of laboratory grade amplifiers (Crown), Tektronix gear, low inductance power resistors, and 33 feet of “regular” 12ga. I’ll do the darned test myself, at any reasonable current level.

If you say we should lose -3dB, we can test it. If you say it is -10dB, we can test it. If your model somehow shows it is -0.09db when it is really tested at -0.06dB, but the TEM model showed it was -0.03dB, then we will indeed be in an interesting position. You will be showing a different model that proves only subtle degradation of signal at frequency extremes similar to what the "wrong" model has already concluded. I really am after the truth here, not just picking on you for your attitude.

That way, we will get away from your claimed credentials, and find out something relevant to the interests of people on this board. Are the claims of specialty cable designers true... or are they fraud?!

BTW, calling me arrogant as a defense for my calling you arrogant... is kinda like me quoting something that you reviewed that seems at odds with claims you make? I'm CHALLENGING you, and you hate it. I'm pretty much leaving out your constant allusions to my "ignorance" from my posts, as I ask YOU questions. I just don't think you like my daring to question you. Hmmm...

[jneutron]

LOL jneutron, that is a funny situation.

Funny is certainly one word for it....Honestly, I found it weird..I was rolling on the floor at the situation when I realized you were pointing to AH.

That way, we will get away from your claimed credentials,

Actually, I have claimed that I know more than you...which of course, was a response to your mockery..normally, I can't be bothered with saying that crap..and I claimed that some guys here are much smarter than me...you're just gonna hafta believe that part, and it's easy enough to verify my input into AH articles...just look for this quote here:
http://www.audioholics.com/techtips/...inductance.php

The theory behind negligible inductance at high frequencies is within a wire carrying DC, there is a uniform current density profile. The magnetic flux within the wire is zero at the geometric center, and increases linearly in value as you move towards the surface of the wire. Outside the wire, the field drops off as 1/R. When a conductor is skinning heavily, as in RF, all the current has moved to the outside surface of the conductor. From the field equations, the field within an infinitely thin cylindrical sheet of current is zero. So, at infinite frequency, the internal portion of the wire has no field, hence, no energy stored, and no inductance. That is how the skin effect alters the internal inductance of the wire.

Or here:
http://www.audioholics.com/techtips/...efaceoff01.php
at infinite frequency, the internal portion of the wire has no field, hence, no energy stored, and no inductance

However, I am still trying to reconcile your model claims, with measurements that you seem to be denying. Please tell all of us cable interested people, HOW MUCH SIGNAL LOSS WE SHOULD EXPECT BASED ON YOUR ASSUMPTIONS at 10KHz, 20KHz, using 10m of regular 12ga. speaker cable.

Disagreeing or questioning is par for the course, I prefer that to blind acceptance..so your questions or disagreement are actually better..

You are thinking of signal loss...that is not what I've been driving at with my research.. it's time shift.

Humans are sensitive to drastically small time shifts, order of 1 to 5 uSec, and from what I'm now working on, for localization, they may be sensitive to absurdly small level variations, quite a ways below what is typically considered accepted JND. This is, in fact, one part of the test regimen I'm working on..but I hadn't realized how small IID has to be to even localize at the one foot level, that I haven't progressed far enough to even bandy a number about..

With inductive storage, it isn't loss, it's the lag...stored energy within the cable eventually goes somewhere, that be the speaker..but because inductive storage is lagging by 90 degrees, and the capacitive storage within the wires is also lagging, the result is a shift in timing..this is what I am looking to test (ITD).

I calculated the energy storage a while back, and found that the energy storage within the cable is approximately 4% of the energy of one lobe of a 10Khz sine..this arrives at the load, 90 degrees lagging..and, much to my suprise, when I plotted the characteristic impedance of the speaker wire vs the energy storage, I found that it is a minima when Z_cable equalled Z_load. graph attached..gotta have dem gratuitious graphs..:-)

Then, using your predictions, we can compare to measurements already made using differential display techniques. I have a stack of laboratory grade amplifiers (Crown), Tektronix gear, low inductance power resistors, and 33 feet of ?regular? 12ga. I?ll do the darned test myself, at any reasonable current level.

You need a non inductive load...even dale nh 250's, while bifilar to remove solenoidal inductance, still suffers from physical size..this renders measurement of high current slew damn near impossible with any accuracy. My load, version 2, measures 1.2 nHenries, with zero intercepted B dot error (this is magnetic field collapse loop generated error voltages, which cannot be avoided by normal techniques.) And, you will need a pair of fast IA's to break the loop around the DUT..and a coupla fast CVR's.

I am still developing the test equipment required to perform the tests with any accuracy..and building the loads and electronics.

What kind of power resistor have you that is "non inductive"? The caddocks still have their problems, as do BeO microwave coaxial ones..

If you say we should lose -3dB, we can test it. If you say it is -10dB, we can test it. If your model somehow shows it is -0.09db when it is really tested at -0.06dB, but the TEM model showed it was -0.03dB, then we will indeed be in an interesting position, You will be showing a different model that proves only subtle degradation of signal at frequency extremes similar to what the "wrong" model has already concluded.

In my research, I have found that the model of audibility of humans, is only one of a "single speaker" type, while localization is an entirely different animal..localization requires timing fidelity channel to channel on the order of a microsecond or two, this is not gonna be easy..and as far as I know, nobody out there has characterized an amplifier to that level, in a reactive load, in all four quadrants of operation..

I really am after the truth here, not just picking on you for your attitude.

My "attitude", is a direct result of your mocking without understanding..you do not yet understand skin theory (which is a trivial issue btw, as most don't anyway..they learn in school, exactly what you and I did, I only learned better as a result of work with superconducting magnets), and your not understanding what I am all about. Repeatable, documented, per reviewed results are all that matter..but, what to test has been lacking, so I work on that as a precursor..

Are the claims of specialty cable designers true... or are they fraud?!

The explanations I've seen are ridiculously incorrect. However, in reviewing human localization capability, I certainly cannot take the approach that "we already know everything there is about the topic".

[Toga]

I did ask you about what you thought thresholds were for time arrival differences in another post. You posted a graph that showed time arrival information, but no human perception levels. I agree it would be interesting to discover where these lie, again to attain design guidelines. At first I thought you didn't understand what I was asking. I see now you are unsure about an answer and are planning to try and discover it.

I DO like that!

I'm very curious what results you will get. I will also be looking for prior art, as my own experience tells me that we may not be THAT good at localization (<1uS range).

You won't be surprised that I don't agree with your assumptions about "perfect" inductors, which indeed exhibit lag behavior being -90 degrees, since other factors can put this in a spread of 0 to -90. Signal reflections from impedance mismatches again have to be related to perceptual capability based on ratios of energy emitted by the load.

The frightening reality is that component tolerances used in professional audio gear are egregious. Often +/-20%, but even +/-1% in cumulative error is enough to ruin localization at the level you are suggesting we could hear. Ironically, Sonic Holography or Binaural recordings could help greatly. In the case of headphone use double blind testing could occur WITHOUT the influence of interaural crosstalk, speaker placement, radiation patterns, crossover phase shifts, and higher than signal level wire currents. Much of this could all be avoided in even decent headphones. Instead of relying on recorded signals, the testing could be done in a "live" setting with carefully channel matched minimalist circuitry between the microphones and the headphones. Much like at the Optometrist's (is this different from this?)! Sound sources could be actual acoustical instruments, like a clacker. Its exciting to even think about the determination being attempted...

The resistor array of a low inductance design is in line with the kind of impedance curve observed in a leaf tweeter. As you will note, I said LOW inductance, such that the reactance is negligible in the face of the overall DC resistance at audio frequencies. This would be as ideal a load as you would encounter in a speaker. Another alternative would be using a well regarded Morel MDT33 1" dome tweeter, which unlike a say a JVC leaf tweeter, can tolerate higher short-term power dissipation. Arguments about low inductance could be set aside since this is a typical high frequency driver arrangement. Low duty cycle tone bursts at upper power levels and a digital storage scope would allow the display of amplitude AND time domain differences between the amplifier and DUT leads, with the difference caused by the intervening interface (speaker wire).

[Toga]

Wait jneutron!

I think I've tripped over a bias in my approach to you, leading to disrespect. I assumed you MAKE AND SELL AUDIO CABLE, or INTEND TO. Please be honest about this, because it does color my judgement when someone purports to have new science unavailable to or not understood by the mainstream technical community, as a justification for financial gain. If instead your primary motivation is sharing what you have learned in a rarified area of study in EM theory and applications, you become a valuable resource for such information to the audio community if you can show you are right in both theory and testing. See where I'm coming from?

This is not to say it is impossible that an ethical researcher/business person can't be one and the same person. But we live in a world where that just doesn't happen very often. I've asked before, what is left to sell that is better, when science might show the differences that are there don't matter?