Bi-wiring The question that can't be answered?

[Mash]

Were you to visit a group of engineers in a design meeting, you might get to see blood on the floor. So one engineer or ten engineers say this or that. Is that gospel? Hell no! Nothing is gospel until the design is built and proven in operation with hard data. The constant competition of ideas amongst engineers drives innovation.

Having some people standing around and listening to various speaker wires that they are watching being “tested” proves NOTHING. This is simply not any kind of reliable performance-verification data. Verified hard data would require a controlled DBT.

Opinions that likely involve marketing considerations more than engineering to optimize performance are worthless.

One racecar driver was asked if he used STP in his engine, since STP was one of his sponsors. “Yes, but not enough to hurt anything” was the answer. So how does providing bi-wiring capability HURT any of those speakers?? It does not, and cannot.

This is NOT the same as saying that bi-wiring HELPS those speakers. If Audiophiles believe that the bi-wiring feature suggests a more desirable high-end speaker, why not provide it? The manufacturing cost is nothing.

And why would you EVER argue with your Audiophile customers who perceive the bi-wiring feature as suggesting a more desirable high-end speaker? Why argue with your customer, and thereby imply to your customer that you think he is stupid or uninformed? Customers do not like to be thought stupid or uninformed, and doing anything that MIGHT imply that you consider them stupid or uninformed is very, very bad for business. Get a clue, man!

Therefore, no matter what you were told, you have no clue how much marketing and how much solid engineering is involved in what you were told. You simply do not know and they will not tell you, but this does not seem to dissuade you from assuming you know. Remember, without real data, you are just another Dude with an opinion.

I have had many disagreements with many engineers, and many engineers did not run their projects as I ran mine, nor did they bring the breadth and depth of knowledge to their projects that I brought to mine. One of my last projects was a simple cycle power plant that could be built in 4 months and would offer 44% baseline efficiency and up to 50% efficiency with options. This was an entirely new concept but was perfect for countries with narrow gage railroads and bridges with limited weight ratings because the components were light and quick to assemble at the site. And another first: all assemblies were tested as 3D models using “Jack-and-Jill” computer-simulated assembly workers.

As a comparison, our advanced bottom cycling steam cooled power plant that I had my fingers in (both arms, actually) offered 60% efficiency and required almost two years to build. The turbine rotors ALONE weighed over 230,000 pounds.

Our goal for this simple cycle power plant was 108MW on a 69F day. Of course, output drops off a lot as the ambient temperature rises above 69F. The first unit was built and run without incident, and produced 108MW on a 94F day. That is just one hell of a home run. And those results were verifiable hard data, not opinions. So I produced a constant-output power plant that was built and run without flaws the first time. Did other engineers agree with my decisions every step of the way? Hell no! But in the end I had hard data, and not hand-waving opinions, that showed a major success.

You will never get hard data in those bi-wire listening sessions, but so what. Bi-wiring will NOT hurt anything, and it IS fashionable. You just cannot prove with hard data that it helps anything. That is the distinction that a critical thinker can appreciate. I really think you need serious tutelage on critical thinking from Skeptic. Now. Your retirement time WILL arrive, and you had better be prepared!

[E-Stat]

And why would you EVER argue with your Audiophile customers who perceive the bi-wiring feature as suggesting a more desirable high-end speaker?

Ah yes, the Great Wire Selling Marketing Conspiracy in action.

rw

[Mash]

This is a response to a point that I never made, nor that I even contemplated. So I do not understand it.

I was writing about marketing concerns and engineering concerns being entwined, and that YOU will not know which was preeminent. And I also noted that the people to whom you spoke would not tell you which was preeminent.

I was posting the question: What audio company that wishes to prosper would EVER imply disagreement with their Audiophile customers who perceive bi-wiring as a feature that is needed for a high-end speaker? Why would these companies tell their Audiophile customers who wish to bi-wire that they do not need to bi-wire and thereby imply to their customer that the customer is stupid or uninformed when there is simply no risk to anyone involved?

I knew the man who ran Roper’s Chain Saw Division. He had no problem telling his customers not to do something that was stupid and/or dangerous. Why??? Because those stupid and/or dangerous acts posed a serious risk to the person involved. You can loose large body parts to a chain saw. It is all about Judgment.

You want to understand that if you push or encourage people to spend their time and money for “improvements” that are later found to be meaningless, most people will decide that they want nothing more to do with you.

I have noticed over the years that the FOO-FOO-Dust Mavens often become quite agitated when someone points out why their favored emperor has no clothes. I had not noticed such behavior from the “other side”, or in your world, “the Dark Side”.

[E-Stat]

This is a response to a point that I never made, nor that I even contemplated. So I do not understand it.

Perhaps you might expand on what you meant by these comments:

These wire debates never contribute anything really meaningful for anyone except those who sell wires.

I was writing about marketing concerns and engineering concerns being entwined, and that YOU will not know which was preeminent. And I also noted that the people to whom you spoke would not tell you which was preeminent.

So it is your feeling that the principals and engineers of dozens of different audio companies will ALL lie to you or the press in a heartbeat when it comes to this topic. Hmmm. I've met quite a few designers over the years through my reviewer friends. I don't share your pessimistic view. Do you likewise have no integrity when it comes to your job? If not, then why do you think that everyone else is different?

I was posting the question: What audio company that wishes to prosper would EVER imply disagreement with their Audiophile customers who perceive bi-wiring as a feature that is needed for a high-end speaker? Why would these companies tell their Audiophile customers who wish to bi-wire that they do not need to bi-wire and thereby imply to their customer that the customer is stupid or uninformed when there is simply no risk to anyone involved?

So it is your contention that inept audiophiles, not engineers "concocted" this idea and through broad communication, planted a false seed in all their minds that is totally beyond the ability of knowledgeable manufacturers to counter?

I have noticed over the years that the FOO-FOO-Dust Mavens often become quite agitated when someone points out why their favored emperor has no clothes. I had not noticed such behavior from the “other side”, or in your world, “the Dark Side”.

Who are these "FOO FOO Dust Mavens" to which you refer? Do they wear black masks?

rw

[jneutron]

Bi-wiring will NOT hurt anything, and it IS fashionable. You just cannot prove with hard data that it helps anything. That is the distinction that a critical thinker can appreciate.

If I ever need a 100 Mw powerplant, I'll give ya a call.

I noticed you've not discussed any of the actual math I've posted which clearly defines the difference between bi and mono wiring.. Why?

Cheers, John

Oh, ps...(I don't sell wire)

[Mash]

Let’s see, E-Stat, how hard this is to parse out "These wire debates never contribute anything really meaningful for anyone except those who sell wires."

1. Well, if the wire manufactures were to sell twice as much wire because all Audiophiles became convinced that bi-wiring is “mandatory”, it is obvious that the wire manufacturers will make more money if their prior profit margins were maintained. So, universal adoption of bi-wiring should contribute meaningfully to those who sell wires.

2. Some Audiophiles already bi-wire for whatever justification while others do not. Audiophiles still have debates about whether or not bi-wiring is really beneficial, which says that these benefits have not been proven to the entire Audiophile world. The methods that might provide the required proof is a different question, but they must be transparent. Spending money on a practice not proven to be a benefit to the Audiophile would constitute wasted money for the purchaser, i.e. we cannot now state that the Audiophile does benefit. [An example of something accepted as beneficial: All Audiophiles agree that some kind of amplifier is needed if one wishes to use loudspeakers. No DBT have been documented that prove some kind of amplifier is ‘mandatory’ with loudspeakers, but every time loudspeakers are employed, so is some kind of amplifier.]

3. We will agree that “speaker manufacturers” do not sell wires, so there is no way for them to benefit whether wire sales should increase, decrease, or remain the same.

E-Stat can continue this exercise in the privacy of his bedroom, and no one will know except Homeland Security**.
**Motto: We ask, we tell.

Originally Posted by Mash...I was posting the question: What audio company that wishes to prosper would EVER imply disagreement with their Audiophile customers who perceive bi-wiring as a feature that is needed for a high-end speaker? Why would these companies tell their Audiophile customers who wish to bi-wire that they do not need to bi-wire and thereby imply to their customer that the customer is stupid or uninformed when there is simply no risk to anyone involved?

“So it is your contention that inept audiophiles, not engineers "concocted" this idea and through broad communication, planted a false seed in all their minds that is totally beyond the ability of knowledgeable manufacturers to counter?” E-Stat

Speaker manufacturers already know that if you win the argument with your customer, you will loose the sale.

Teasing aside, E-Stat, we DO consider you our own High-End Audiophile Master. But you posted “inept audiophiles”? That is not nice from our High-End Audiophile Master! Why should you need to push silly words into someone else’s post? Why do you, Master, need to create a "concocted"-this-idea straw man and then beat the crap out of it?

Remember President Carter’s RIF which was “Reading is Fundamental”? Do you read anything besides Audiophile material? There is a book that will answer your questions: “Popular Delusions and the Madness of Crowds”.

I personally enjoy your pedantic style. I know you will have the last profound word, and everyone will await pronouncements from the guiding High-End Audiophile Master, baited breath and all.

[E-Stat]

1. Well, if the wire manufactures were to sell twice as much wire because all Audiophiles became convinced...

I agree there will always be some guys who buy stuff just because they think they should. I remember one sterling example we (at the audio shop where I worked in college) used to call Al Gear. It was crazy. He bought a pair of DQ-10s from us. Sold them. Bought another pair. Sold them. Bought some Maggies. Sold them. Finally, he bought third pair. All this to listen to his vast collection of twelve records. On the other hand, all of my audio buddies (most of whom are/were reviewers) make choices upon their experience. If it works, use it. If it doesn't, don't. It's that simple. One of them tri- wires his Avalons and the other bi-wires his Nola Grand References (the woofer towers are amplified separately). Virtually all the cables I've purchased (remember I cannot biwire my full range stats) were based upon a thirty day money back trial period. Keep them if you perceive value addressing the complex interactions between your speaker driver(s) and amplifier(s). Take them back if you don't. With my double New Advents, I use short jumpers between the upper and lower speakers. There an engineer over at AA who uses separate runs. He suggests that works better, but I confess I haven't tried it out. Will it require throwing more money at the evil wire industry? No. I've still got about 70' remaining on the spool of the 14 gauge stuff I use for them.

Speaker manufacturers already know that if you win the argument with your customer, you will loose the sale.

You just restated your point and didn't answer the question. You presume that what started the whole issue was audiophile gossip, not the speaker manufacturers (a whole bunch) offering that feature to improve performance, however subtle, in order to sell more of their product, not that of the wire industry.

rw

[jneutron]

[quote=Mash]Math’ would not be transparent proof of a PRACTICAL benefit. /quote]

Given your propensity to expound on how far above your peers you stand, I am shocked to see that you avoid simple math.

If I presented a mathematical analysis on your powerplant "stuff", pointing out how you could pick up an additional 1.5%, you'd say, what...Math’ would not be transparent proof of a PRACTICAL benefit.""

Clearly I made a mistake in assuming you had any desire to discuss the topic, but you would rather take potshots at others.

If you change your mind, and are willing to learn (or at least listen), I will be here.

Sheesh, room temperature rotating machinery...such simplicity. Try doing it at liquid helium temps, or even liquid nitrogen..where the math you used in the past (but now avoid) falls apart, like the materials.

Cheers, John

ps..demeanor chosen specifically to match yours.

[kexodusc]

This is the best muther****in thread I've read on any audio site, anywhere, in months....keep going guys...

I've always felt bi-wiring could help, but just haven't been able to confirm it on any setup I've tried yet.

For the benefit of those eager young learners here like my good ar.com buddy, uh, Mexodusc, who's probably the least educated in this thread in such things, there's a few things I'd love to have explained.
It would seem to me, the differences in currents of each wire to woofer and tweeter at each frequency would somehow react differently with the downstream crossover filters compared to a single wire splitting after the speaker terminal, very shortly, before each filter. But I'm no EE and can't really conclude by myself if this is true. Are the currents in the wires to woofer and tweeter after the speaker terminal of a mono-wired speaker system not also different with each frequency? If so what's the benefit of having a different current over a longer length of wire?

And, does this generate enough of a difference to be heard by the average human ear? Is there any measurement supported research available on this matter? What were the conclusions?

And what effect, if any, does bi-wiring have on the time domain and phase of the system?

[jneutron]

I've always felt bi-wiring could help, but just haven't been able to confirm it on any setup I've tried yet.

I believe audibility testing for it has a huge error component which prevents accurate discernment....us..

For the benefit of those eager young learners here like my good ar.com buddy, uh, Mexodusc, who's probably the least educated in this thread in such things, there's a few things I'd love to have explained.
It would seem to me, the differences in currents of each wire to woofer and tweeter at each frequency would somehow react differently with the downstream crossover filters compared to a single wire splitting after the speaker terminal, very shortly, before each filter. But I'm no EE and can't really conclude by myself if this is true. Are the currents in the wires to woofer and tweeter after the speaker terminal of a mono-wired speaker system not also different with each frequency? If so what's the benefit of having a different current over a longer length of wire?

And, does this generate enough of a difference to be heard by the average human ear? Is there any measurement supported research available on this matter? What were the conclusions?

And what effect, if any, does bi-wiring have on the time domain and phase of the system?

Ahhhh...the last question is by far the best..I'll discuss it at the end..

Where to start, so that Mexodusc can clearly understand...

Take a one way system. 8 ohms resistor, with wire at say, .1 ohm total.

Put a sine wave into it, 4 amperes peak current. When the current is at the top of it's waveform, the 8 ohm resistor will dissipate I squared R, or 4 squared times 8, 16 times 8, or 128 watts. The wire will heat up, the power lost to the wire will be 16 times .1, or 1.6 watts. Again, the wire will have it's maximum power loss at the exact same time as the resistor (load). When the wire has zero current, no loss in either the wire or the resistor.

Now, make two of these systems, with 20 hz playing in one set, 10Khz playing in the other. Each will do the exact same thing, but of course, based on each current. At the instant in time when the 20 hz signal is at 4 amperes, and the 10Khz signal is at 4 amperes, what is the power loss in the wires? Simple, it is 1.6 watts times 2. This is the biwire configuration. When the 20 hz signal is at +4 amps, and the 10Khz is at -4 amps, what is the power loss?? Simple again, both are losing 1.6 watts. (remember, when you square a negative number, the result is positive..)


OK, now..let's make a system with two resistors, and a crossover network so that the 20hz gets to one resistor, and the 10Khz to the other.. And, lets push the amplifier so that there is 4 amperes of 20 hz and 4 amperes of 10Khz.

Let's look at the same points in time as before..

When both signals are at +4 amperes, each resistor STILL dissipates 128 watts. What is the single wire dissipating?? The current in the wire is 4 + 4, or 8 amperes. Power = 8*8 (I squared) times .1 ohm...or 64 times .1, 6.4 watts.

With the biwire setup, there is 1.6 plus 1.6 watts being lost to the wire..3.2 total. This means that using one wire to move both currents causes twice as much loss in the wire as the biwire case.

Now, bass at 4 amps, highs at -4 amps. With a single wire, the wire current is ZERO, so there is no power being lost to the wires. But a biwire setup loses 3.2 watts at this time.

So, recap:
1. When biwiring is used, the peak power loss is 3.2 watts, where the peak loss in monowire is 6.4 watts.

2. When monowiring is used, there will be times when there is no wire loss, and at the same time, biwiring will lose 3.2 watts.

3. If you go through the math, you will find that the average power loss within biwiring will be the same as the monowiring....

4. It is not possible to select a monowire guage which will make it lose power exactly like biwiring does. They are different.

This difference, for the simple back of the envelope calculations I present, is 1.48%.

My contention is that this difference, by it's nature, cannot be seen using an FFT analyzer. But yet, the difference is there, this is clear from the math.

This power loss will be assymetric to the hf, and it is dependent on the lf, I do not know how this plays out in audibility. However, if the bass signal in the right and left channels is different, the modulated losses will also. I suspect this will wreak havoc with localization (spacial imaging).

Cheers, John

ps..if Mexodusc has more questions, relay them here, and I will answer to the best of my ability.

[FLZapped]

The designers will not have correct engineering reasons. None of them ever do. Talking with them will be useless.

That doesn't mean biwiring is incorrect, just that they do not understand.

Cheers, John

Probably because it is driven by the marketing department, not the Engineering department......

Happy Thanksgiving, John.

-Bruce

[jneutron]

Probably because it is driven by the marketing department, not the Engineering department......

Happy Thanksgiving, John.

-Bruce

Hey there Bruce, long time no talk..Happy thanksgiving to you.

How are you doing? Hope all is well.

I'zis just doin fantastic...still wakin up on the right side of the ground.. Gettin ready ta make the old woodwork shop so'z I can get to the spkr projects.

Course, my time here may be limited...after all, I'zis violatin rule #4..

Dat be:

Please restrict discussion of DBT, ABX and lab measurements to the "The Science Lab"


Oh well..what iz.....iz..I'ziz livin at the discretion of a moderator, I guess..

Cheers, John

[FLZapped]

getting a little heated and opinions are coming in. I base mine of facts. Here is a link to a typical bi-wire scheme:

http://www.st-andrews.ac.uk/~jcgl/Sc...ire/Page1.html

Notice the jumpers? It's not like you take two sets of hots/negs and connect the two hots to amp hot and the two negs to the amp neg. You have one wire from the amp pos/neg and then little jumper wires to attach to the speaker terminals. Like I said before, "One signal feeds both" in this arrangement. The xover is what separates the highs from the lows. The amp has nothing to do with splitting the signal. And just because you jump it to the extra terminal doesn't mean that signal changes. It doesn't change until it goes into the xover and that's what bends the signals. So to recap for those hard of getting it. You have an amp, you run a wire from the amp to the speakers. You splice into the wire and add some jumpers and route them to the other terminal. Same signal, same amp, same everything except those little jumper wires going to different speaker terminals.

Bi-Amp has some merit. This is where you take a separate amp for each driver (one for the tweeter, one for the mid, one for the woofer, etc). In a two way speaker this means you need four amps to run a bi-amp. Two amp channels for each speaker. One channel to the tweeter, the other to the woofer in a two way. Why would this help? Well, think about it. The woofer is the power hungry guy. It may take the full 100watts and leave the leftovers for the mid and tweet. Probably driving them into distortion. With 1 amp on the woofer and one on the tweeter you don't have that problem. Just because the woofer distorts doesn't mean the mid or tweeter will because they are on separate paths.

Anyway, I've typed until I'm blue in the face so if you don't get it by now, maybe you will get it in the future or then again, you may never get it. Good luck.

Paul

Paul, you missed a little something here.

Using Scots guide.

Figure 1. Coming from the amp you have both a voltage signal and a current signal.


So in figure 1, you have all the voltage and all the current through a single wire pair being delivered to the speaker.

On to figure 2. While you have the same total load connected to the amp, there are two different paths. So now you have all the volage on both wire pairs, since they are in parallel, but you have two different currents in each wire pair, which is controlled by the properties of each half of the crossover.

-Bruce

[kexodusc]

Thanks jn, it's a real treat having you here when you do drop by. I don't have the time to devote studying all this stuff myself, it's nice to get some simple answers to help me guess if I'm being BS'ed by biwire yeah or naysayers when these debates pop up from time to time.

I believe audibility testing for it has a huge error component which prevents accurate discernment....us..

Fair enough. Though I might question how "huge" in some cases, when the human ear can pick up on small changes in LCR in the crossover components. I'm in the camp that if it falls in that region of error, it's not significant enough for me unless it's really cheap and easy to do. Guess I'd make a bad audiophile.

Ahhhh...the last question is by far the best..I'll discuss it at the end..

Look forward to it..

So, recap:
1. When biwiring is used, the peak power loss is 3.2 watts, where the peak loss in monowire is 6.4 watts.

2. When monowiring is used, there will be times when there is no wire loss, and at the same time, biwiring will lose 3.2 watts.

3. If you go through the math, you will find that the average power loss within biwiring will be the same as the monowiring....

4. It is not possible to select a monowire guage which will make it lose power exactly like biwiring does. They are different.

This difference, for the simple back of the envelope calculations I present, is 1.48%.

My contention is that this difference, by it's nature, cannot be seen using an FFT analyzer. But yet, the difference is there, this is clear from the math.

This power loss will be assymetric to the hf, and it is dependent on the lf, I do not know how this plays out in audibility.

Okay. Your example assumes isolated frequency signals in both wires, 20 Hz and 10 kHz. Is this for the benefit of simple calculations (to make it simple for poor Mexodusc)? I think it's fair to say that most music sources would demand an amplifier send multiple frequency signals across each wire, and your example would be an extreme situation.
This begs the question, in practical terms, if each wire is going to see more than 1 individual frequency at a given point in time, and thus resulting in different currents in each wire as a result of the different reactance of each filter/driver for those frequencies, will the power loss differences between biwiring and monowiring therefore be smaller in most cases than 1.48%? Sometimes zero?
(I'm rambling a bit here, but just hoping you'll point where I get lost if/when it happens).

Knowing what I do know about drivers, when you change the power of the signal fed to the driver, the FR must change at least a bit between these two wiring setups. I'd consider this as being analogous to placing a small resistor in series before the filter (or a really small pre-filter tweeter pad). At lower SPLs, 1.5% power loss differences are probably significant...but with the logarithmic relationship of power and SPL, I'm guessing the audible difference the 1.48% power difference generates is extremely small. Smaller than 1.48% at max, at any rate Maybe I'm way off But that's just FR and I'm sure there's distortion, time and phase considerations not accounted for (yet).

Cheers, John
ps..if Mexodusc has more questions, relay them here, and I will answer to the best of my ability.

Just don't forget the time/phase stuff....

[jneutron]

Though I might question how "huge" in some cases, when the human ear can pick up on small changes in LCR in the crossover components. I'm in the camp that if it falls in that region of error, it's not significant enough for me unless it's really cheap and easy to do. Guess I'd make a bad audiophile.

heh, me too. I use #12 for 100 foot runs, without regard to biwire stuff. It's a convienience thing.

Okay. Your example assumes isolated frequency signals in both wires, 20 Hz and 10 kHz. Is this for the benefit of simple calculations (to make it simple for poor Mexodusc)?

No, silly. It's for the benefit of ME..I can't handle the more complex problem. Same thing applies to 3 way systems, but the math gets even worse.

I think it's fair to say that most music sources would demand an amplifier send multiple frequency signals across each wire, and your example would be an extreme situation.

yes, it is

This begs the question, in practical terms, if each wire is going to see more than 1 individual frequency at a given point in time, and thus resulting in different currents in each wire as a result of the different reactance of each filter/driver for those frequencies, will the power loss differences between biwiring and monowiring therefore be smaller in most cases than 1.48%? Sometimes zero?

beats me ...I would think that my numbers were the max, and it ranges from that to zero. I used equal power highs and lows also, which doesn't happen without trashin the tweet. So for typical program information, my guess is that it may or may not be audible, normally falling below jnd"s.

At lower SPLs, 1.5% power loss differences are probably significant...but with the logarithmic relationship of power and SPL, I'm guessing the audible difference the 1.48% power difference generates is extremely small. Smaller than 1.48% at max, at any rate Maybe I'm way off But that's just FR and I'm sure there's distortion, time and phase considerations not accounted for (yet).

Ya gotta remember, this is not a overall power loss, that remains constant..it is an instantaneous loss, sometimes it is double, sometimes it is zero. This variation in loss will show up as less and more power to push the voice coil around, based on the lows..so, that will alter the timing of the highs based on program content. That'd be the timing part of ITD. It should be consistent with bass induced phase modulation.
Honestly, I don't know how to test that for audibility.

Cheers, John

ps...discussing this with Bob Lee...could get interesting..but then again, he may just consider me a "slow learner"..(gotcha Paul... )

[hermanv]

When both signals are at +4 amperes, each resistor STILL dissipates 128 watts. What is the single wire dissipating?? The current in the wire is 4 + 4, or 8 amperes. Power = 8*8 (I squared) times .1 ohm...or 64 times .1, 6.4 watts.

It seems to me that the woofer current heats and allows the wire to cool at 20Hz. Since copper wire changes resistance with temperature the woofer current will now modulate the 10KHz tweeter signal. Not by much but it will, I haven't measured or calculated the disturbance, but I'm sure there is one. Audible? Maybe.

The point is that when talking about audio quality in an environment with 96dB (Redbook CD) dynamic range, very small effects can be audible. Most equations about wire look only at first order effects i.e. resistance, when second and third order effects are included the situation becomes far more complex. The too simple, wire is wire argument doesn't include any of these factors. In modern equipment with oversampling, upsampling and iteration the dynamic range can be better yet with some claiming over 100dB)

Some of these high order effects include: Magnetic interaction, constriction and expansion with current, EMI, dielectric loss and absorbtion, eddy current losses, thermionic effects and piezo electric effects. I am not saying that one or any of these I listed explain the issue, I am simply saying that the question is more complex than simple Ohms law although even Ohms law provides some insight. The effects I mention can be measured, but I don't know anyone who has correlated these measurements with an audible effect if any.

The point is that the earth orbited the sun long before anyone measured orbital mechanics and proved the sun couldn't orbit the Earth. I can listen and hear a difference that satisfies my subjective criteria. I am quite happy to exploit this difference and while I wouldn't mind an explanation one is not necessary for me to enjoy what I hear as a benefit.

[jneutron]

It seems to me that the woofer current heats and allows the wire to cool at 20Hz. Since copper wire changes resistance with temperature the woofer current will now modulate the 10KHz tweeter signal. Not by much but it will, I haven't measured or calculated the disturbance, but I'm sure there is one. Audible? Maybe..

No no no, don't worry about wire heating. a coupla watts over 5 to 10 feet is nothing that'll affect anything.

Some of these high order effects include: Magnetic interaction, constriction and expansion with current, EMI, dielectric loss and absorbtion, eddy current losses, thermionic effects and piezo electric effects. .....

no, no, no. Don't worry about those either...those explanation have nothing to do with reality. They are simply made up garbage that has been foisted on the audiophiles.

THAT kind of reasoning is precisely why high end audio guys are looked down upon, and their concerns pushed aside.

I am applying basic knowledge to simple problems.

Problems which I have no stake in..

Cheers, John

[hermanv]

no, no, no. Don't worry about those either...those explanation have nothing to do with reality. They are simply made up garbage that has been foisted on the audiophiles.
Cheers, John

Sorry John. I will happily admit that there is no evidence that any of those effects have anything to do with cable sound, but all those effects are real and can and have been measured, they aren't made up.

[jneutron]

Sorry John. I will happily admit that there is no evidence that any of those effects have anything to do with cable sound, but all those effects are real and can and have been measured, they aren't made up.

You misinterpreted me. Sorry about that, I should have been clearer.

I was referring to affecting cable sound, and how they are "enlisted" to explain something wondrous or bad about somebody's cables...the explanations being foisted are made up, pulled out of a hat..

All of those effects come into play where I work. I have to deal with them daily.

Cheers, John

[Dusty Chalk]

This begs the question, in practical terms, if each wire is going to see more than 1 individual frequency at a given point in time...

Correct me if I'm wrong, but is this a correct assumption? We do fourier analysis when looking at signals, but really, it's still and always will be one signal. A difference potential across the outputs of the amplifier will send electrons scurrying ("...scurrying..." at the speed of light, that is) across the wires to create an analogous potential drop at the other end of the wires, back-EMF notwithstanding. The only multiple-frequency situation will be at the point where the back-EMF interacts with the incoming current.

[jneutron]

Correct me if I'm wrong, but is this a correct assumption? We do fourier analysis when looking at signals, but really, it's still and always will be one signal..

Correct, it is one signal. In a monowire, it is one current. That's not the issue.

The problem starts when it branches to two different loads at the crossover. The loads see their own intended signal, but the monowire sees both. That "both" part changes the power loss in the mono vs the bi set.

A difference potential across the outputs of the amplifier will send electrons scurrying ("...scurrying..." at the speed of light, that is) across the wires to create an analogous potential drop at the other end of the wires, back-EMF notwithstanding..

No. Electrons travel at mm per second.

The only multiple-frequency situation will be at the point where the back-EMF interacts with the incoming current.

Don't even worry about back emf at this time. My analysis does not need it to be correct (or not). Back emf would only confound the situation..let's keep it simple for now, shall we?

Even this simple analysis is not understood by those who should..I am suprised the world of pro audio has gotten as far as it has.

I blame the professors who teach e/m. They have failed to teach the engineers how to extend their "box".

Cheers, John

[Mash]

Well, E-Stat, are you asking the right question? Who knows? Anybody care?

I answered before, but this should be more obvious:

1. I am a speaker manufacturer. My reps and dealers make me aware of a buzz about bi-wiring speakers for better speaker performance. [Maybe some audio hobbyists bi-wired some speakers and declared an improvement and then other audio hobbyists did the same. Maybe a magazine reviewer had made a speculation. I cannot prove any scenario, but I cannot disprove it. You cannot prove or disprove it, either!]

2. A subset of Audiophiles slowly develops that believes that bi-wiring speakers gives better performance. I cannot prove this scenario, but I cannot disprove it. You cannot prove or disprove it, either!

3. Some positive buzz about bi-wiring appears in Audiophile publications. Perhaps the writers happen to believe the audio hobbyists who bi-wired some speakers and declared an improvement. Who knows?

4. But guess what? I am in the business of making and SELLING loudspeakers! I am NOT in the business of telling Audiophiles that they should or should not bother to bi-wire.

5. My reps and dealers provide feedback that a newly discovered subset of Audiophiles will only consider speakers that offer a “bi-wire capability”.

6. I find that my cost of adding “bi-wire capability” is $10 to $25 per pair of speakers. If I add this “bi-wire capability” my speakers will then be considered by that subset of Audiophiles previously identified as only willing to consider speakers that do offer a “bi-wire capability”. What do I do? What do I do?

7. I add the “bi-wire capability” to my speakers. Isn’t this a “no-brainer” if I wish to have the opportunity to sell as many speakers as I possibly can?

8. Now I can leave the decision to bi-wire or not to bi-wire to my customer. There is NO risk of harm to my customer, so why not?

9. If the Audio Magazine doing a review of my speakers has previously opined that bi-wiring is good, why should I not “go along” with them? Remember, I am in the business of what? Selling loudspeakers!


Here is a TRUE story about bicycles that shows you how shift can happen”:

I remember that c1985 aluminum bicycles began to appear and were perceived as alternatives to CrMo steel bicycles. An early reviewer of an early aluminum bicycle determined that that new aluminum bicycle had a much smoother ride than contemporary steel bicycles he had ridden. He POSTULATED that “aluminum must have better damping qualities than steel”. NOTE the wording: “…must have better damping qualities….”

By c1988 reviews of aluminum bicycles always concluded that the aluminum bicycle being discussed had a better ride than a similar steel bicycle “because of the inherently better damping qualities of aluminum compared to steel”. Did you notice the change in wording, “ inherently better ”???

So you see, as more and more reviews of aluminum bicycles were published the SPECULATION “aluminum must have better damping qualities than steel” became the FACT “because of the inherently better damping qualities of aluminum compared to steel”.

I became peeved about this nonsense one (slow) day and sent a letter to the largest bicycling magazine pointing out chapter and verse on damping characteristics of structural materials, with full documentation of structural materials references, that

1. If steel and aluminum are both stressed to the same percentage of their Young’s Modulus, which represents identical strains in the metal, the steel has 3X the damping of aluminum.

2. The damping contributed to any structure by either material was completely insignificant anyway. Bolted joints, for example, provide a very small amount of damping, but aluminum and steel effectively provide no structural damping.

They published my comments and from then on, NO reviewer of an aluminum bicycle ever again wrote: “aluminum must have better damping qualities than steel”, or “because of the inherently better damping qualities of aluminum compared to steel”.

Moral: E-Stat, You may be asking the wrong question.


Great job, jneutron, but where here have you provided your “transparent proof of a PRACTICAL benefit” I missed it. The last line seems to say "yes and no"....


So, jneutron, here is your recap for our reference:

1. When biwiring is used, the peak power loss is 3.2 watts, where the peak loss in monowire is 6.4 watts.

2. When monowiring is used, there will be times when there is no wire loss, and at the same time, biwiring will lose 3.2 watts.

3. If you go through the math, you will find that the average power loss within biwiring will be the same as the monowiring....

4. It is not possible to select a monowire guage which will make it lose power exactly like biwiring does. They are different.

This difference, for the simple back of the envelope calculations I present, is 1.48%.

My contention is that this difference, by it's nature, cannot be seen using an FFT analyzer. But yet, the difference is there, this is clear from the math.

[jneutron]

Great job, jneutron, but where here have you provided your “transparent proof of a PRACTICAL benefit” I missed it. The last line seems to say "yes and no"....


So, jneutron, here is your recap for our reference:

1. When biwiring is used, the peak power loss is 3.2 watts, where the peak loss in monowire is 6.4 watts.

2. When monowiring is used, there will be times when there is no wire loss, and at the same time, biwiring will lose 3.2 watts.

3. If you go through the math, you will find that the average power loss within biwiring will be the same as the monowiring....

4. It is not possible to select a monowire guage which will make it lose power exactly like biwiring does. They are different.

This difference, for the simple back of the envelope calculations I present, is 1.48%.

My contention is that this difference, by it's nature, cannot be seen using an FFT analyzer. But yet, the difference is there, this is clear from the math.

A correct recap. Add in that the numbers are with 8 ohm loads and 120 milliohms of resistive wire, and that it is with equal amplitude orthogonal 4 ampere currents that branch to different 8 ohm loads.

The last line is not saying yes and no. It says that an integral zero power signal is not necessarily visible by methods which look for integrated power.

Any difference of 1.5% with an audio signal must be reviewed for audibility. To make the assumption that that magnitude of error is of no consequence and therefore "of no practical benefit" is quite premature, shall we say??

A signal which is present, but is not visible to the measurement instrument, just cries out "fix the instrument". Well, at least to me it does. Audibility, that's for others.

Kinda like using an AC voltmeter to measure DC...the results are inaccurate and have consequences.

Cheers, John

[Dusty Chalk]

No. Electrons travel at mm per second.

According to this page, I phrased the statement incorrectly. The electrical signal travels at the speed of light. Wikipedia concurs.

[hermanv]

Over the years I've posted several times about the whole cable sound issue. I'd like to repeat a short form of some of those posts. I am a believer, if you're not, save both of us some pain and skip to the next post.

1. I am an EE by trade, professsionally I was strongly biased against the whole wire has a signature phenominum. I did a little math and quickly concluded the differences between any two reasonable wire choices would be so small as to be inaudible.

2. My dealer recommended I borrow a speaker cable and listen for myself. I invited over several friends to attempt a test. No, it was by no means a blind test.

3. The results surprised everyone in the room, one wire set was clearly cleaner sounding than the other, both were a reasonable gauge 12 and 14 I think (It was many years ago and the smaller gauge was the better sounding).

4. Many years later I had gravitated to fairly expensive wires and decided I just couldn't afford the next step up. So my friend and I set about making our own cables. We did a lot of reading on the various manufacturers sites and soon discovered some clear parallels in what each manufacturer was doing.

5. We made several cables, each step up in sound quality was obtained by emphasizing what the cable manufacturers said would work (low dielectric absorbtion for interconnects, low inductance and large gauge for speakers, we also confirmed that high metal purity and quality connectors were needed to get the best out of any given design).

6. The cables got more complex, the materials cost went up and the quality, as we heard it, kept getting better. It was about at this point that we discovered much to our surprise that the cable vendors were not on the whole ripping anybody off. To make cables as good as their best involved very expensive materials and connectors. Allowing for some profit and mark-up, our best cables cost about half of the commercial competition, but we had no labor, packaging, avertizing or distributor mark up costs..

7. The best commercial cables unfortunately involve construction techniques that simply can't be duplicated at home. i.e very high conductor counts and lots of thin wall teflon tubing or better yet foamed teflon for interconnects and just sheer volume of high purity expensive metals aranged in a Litz wire configration for speakers.

Cables affect the soud of every quality audio system I've ever heard, Although I know some techniques to make cables that sound better, I don't know all the reasons why this should be so.

Borrow some cables and listen for yourself. It costs you only time and might just increase the enjoyment of your system.