Why Bi-wiring Makes No Sense.

[Omicron]

You young ones crack me up..I used to think it fun playing with my food. Now it can be an annoyance..

*sigh*

Let me just defeat you with your own words then. This is what you wrote at the conclusion of our discussion about this same topic 2 years ago on the diyaudio forum:

----start quote-----
What is needed is to look at the system in segments, divided by an arbitrary line.

If one uses biwiring, select the segmentation to be between the amp and the cable plus loads.

Look at the amp which has A+B as an out, with it's dissipation of (a+b)2, while the load is split into two squares only.

Vs the monowire case, where one must set the segmentation AT THE branch juncture.

By segmenting at the juncture, the amp AND the wire both share the exact same power profile, while the load has the same one as always.

Where I was unable to consolidate the different power profiles was solely determined by where that segmentation occurs.

This view now squares entirely with what we were taught, and is consistent with what you have been stating..

I am now happy...and can easily reject the hypothesis that the selection of wiring scheme alters the signals via the 2ab component of a mixed signal power profile..perhaps in the near future, when I have my workshop back up, I will endeavor to do a test setup to confirm what we already understand..

Course, there are a few people who were on the railroad with me who were concerned with my sanity..did you realize that kinetic energy, gravometric potential, capacitor and inductor energy equations all share the same constructs as resistor dissipation?...(it is scary when I am given free time to dwell on this goop).

Kurt (and all others), it has been a distinct pleasure..thank you for your time and patience..

----- End quote ------

Cheers, Kurt

 

[bandphan]

ok girls, enough... i can pee further than both of you , put it to bed, or pm... close this thread

 

[jneutron]

*sigh*

Let me just defeat you with your own words then. This is what you wrote at the conclusion of our discussion about this same topic 2 years ago on the diyaudio forum:

----start quote-----
What is needed is to look at the system in segments, divided by an arbitrary line.

If one uses biwiring, select the segmentation to be between the amp and the cable plus loads.

Look at the amp which has A+B as an out, with it's dissipation of (a+b)2, while the load is split into two squares only.

Vs the monowire case, where one must set the segmentation AT THE branch juncture.

By segmenting at the juncture, the amp AND the wire both share the exact same power profile, while the load has the same one as always.

Where I was unable to consolidate the different power profiles was solely determined by where that segmentation occurs.

This view now squares entirely with what we were taught, and is consistent with what you have been stating..

I am now happy...and can easily reject the hypothesis that the selection of wiring scheme alters the signals via the 2ab component of a mixed signal power profile..perhaps in the near future, when I have my workshop back up, I will endeavor to do a test setup to confirm what we already understand..

Course, there are a few people who were on the railroad with me who were concerned with my sanity..did you realize that kinetic energy, gravometric potential, capacitor and inductor energy equations all share the same constructs as resistor dissipation?...(it is scary when I am given free time to dwell on this goop).

Kurt (and all others), it has been a distinct pleasure..thank you for your time and patience..

----- End quote ------

Cheers, Kurt

Well well...Finally. I was wondering what words would work to draw you out of anonymity..

How's it been?? Long time no talk..

Me, lots and lots of good changes over the years..

I remember writing that also...it was just before I had to leave the country for china for a week (I hate flying) back in dec 2005 I think....I was worried that somebody would take the analysis to it's logical conclusion, so I posted that in haste to divert others from figuring it out....and ya know what...it worked.

People like you figured all along you were correct.. I "laugh" in your general direction..

Seriously, though..Yes, I've spent many an hour trying to find the defects in my arguments. Leseuf couldn't...but he was the best..

In fact, half the physicists I discuss it with understand what I'm talking about.

I work on the other half..

Cheers, John

ps..for some reason, there was some kind of hiccup in the thread display. I didn't see the one (313)when I posted again..

Again, sorry for diverting all away from the problem...I was concerned another would pick it up before I could get back..

 

[stratman]

Dark Helmet: [mask down] Not so fast, Lone Starr.
Lone Starr: Helmet. So, at last we meet for the first time for the last time. [thinks about what he said] Yeah.
Dark Helmet: Before you die, there is something you should know about us, Lone Starr.
Lone Starr: What?
Dark Helmet: I am your father's brother's nephew's cousin's former room-mate.
Lone Starr: What's that make us?
Dark Helmet: Absolutely nothing.

 

[jneutron]

Guess I'd better stay out of this or someone may throw a handgranate at me

As Kurt said...nahh. old friends gettin re-aquainted..

Cheers, John

 

[Alex2507]

Dark Helmet: [mask down] Not so fast, Lone Starr.
Lone Starr: Helmet. So, at last we meet for the first time for the last time. [thinks about what he said] Yeah.
Dark Helmet: Before you die, there is something you should know about us, Lone Starr.
Lone Starr: What?
Dark Helmet: I am your father's brother's nephew's cousin's former room-mate.
Lone Starr: What's that make us?
Dark Helmet: Absolutely nothing.

You're not taking this seriously at all. Even though I don't get it, I still wanna see how it ends.

 

[Omicron]

I was worried that somebody would take the analysis to it's logical conclusion, so I posted that in haste to divert others from figuring it out....and ya know what...it worked.

Yes, well that's a bit convenient isn't it?

I took a look at the website you mentioned, I assume it is this one:

http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/biwire2/page1.html

Note that the system schematic that he starts from is exactly that which I proposed we should discuss. I guess the young ones aren't as stupid after all then.

However my obviously inferior mind can't seem to find any errors in his equations. Care to tell us younglings and straw-men which equation is wrong in your opinion and where exactly he violates the conservation of energy principle?

 

[stratman]

You're not taking this seriously at all. Even though I don't get it, I still wanna see how it ends.

On the contrary Alex! I'm waiting with baited breath to see who'll pull out the light saber first!!! Lord O or Jedi J, the battle rages, as us mere mortals gawk on!!!

 

[Omicron]

On the contrary Alex! I'm waiting with baited breath to see who'll pull out the light saber first!!! Lord O or Jedi J, the battle rages, as us mere mortals gawk on!!!

I for one do not have light sabers lying around

But I think I should try and explain why this thread is dragging on as long as it has. It might at first sight seem as if we are discussing an obscure feature pertaining only to the merits of bi-wiring. But that's not really true. The claims John make in the end boil down to this simple fact:

A linear circuit can cause non linear distortion.

Let me try to explain what this statement means. A linear component such as for example a perfect resistor is a component that is by definition unable to distort the signal. Such components obviously do not exist in the real world but us engineers like to simplify matters. Now one convenient feature of linear components is that when you arrange them into a circuit, the resulting circuit is also linear. Remember, we are talking hypothetical perfect components here. This is a simple mathematical fact that is taught (and proven) in any electrical engineering course. It is as fundamental as say the law of conservation of energy. Every circuit ever built is based on this principle in one way or another.

It is this fundamental principle that is disputed by John. I'm not exactly sure if he actually understands that his claims are violating this principle, but they obviously do because his schematics only contain linear components like wire resistance, capacitors and coils and he is claiming they cause distortion (and remember we are considering hypothetical "perfect" components, we are not arguing about distortions introduced by real life imperfect components).

Many have tried to engage John in a discussion because he seems a knowledgeable person and not the typical crackpot case. You might have noticed some pretty impressive names popping up in this thread. Unfortunately such people usually have little patience when it comes to claims like this. This may leave the casual onlooker to suspect that there might actually "be something to it".

Another thing that is hard to swallow for the electrical engineer is the way John goes about trying to prove his hypothesis. His arguments are always based not on what is going on in the speakers (which is what matters) but on what is going on in the wires between the amplifier and the speaker. John insists on looking at the power losses in the wires when the sound that we perceive is analogous to the current or voltage waveforms of the speakers. To our mind he is looking at the wrong parameter in the wrong place.

The summarize, if John is really right then he will win himself at least one nobel prize and will undoubtedly enter the pantheon of the greatest minds on the planet. I wish him the best of luck.

I hope this post may give some insight to the casual reader about exactly what this discussion is about.

 

[bandphan]

Nigel Tufnel: The sustain, listen to it.
Marty DiBergi: I don't hear anything.
Nigel Tufnel: Well you would though, if it were playing.

 

[Alex2507]

I for one do not have light sabers lying around

What happened to your light saber? Did you lose it?

Sorry, blame Strat.

 

[jneutron]

Yes, well that's a bit convenient isn't it?

Convienient? Hey, it worked..I was quite surprised it worked as well as it did.

The biggest flaw in that plan, IMHO, was Steve Eddy. I was certain that if he got wind of my last post, he would have torn to shreds logically. As luck would have it, he wasn't posting anymore on diy at that time..

I took a look at the website you mentioned, I assume it is this one:

http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/biwire2/page1.html

Actually, no. Sorry, it's page 2..

He show exactly the difference in energy loss within the wires both bi and mono, then ends with this:

""That although the monowired and bi-wired cases show patterns of cable energy dissipation levels which vary with time in different ways, this difference is equal and opposite to the difference in their patterns of energy storage and release in the reactances of the filter networks.""

So, the crossover network knows exactly what to store and what to release, and to do so in a time coherent fashion..?

There is a fundamental flaw in that reasoning...but first you need to understand very clearly the mechanisms..

Note that the system schematic that he starts from is exactly that which I proposed we should discuss. I guess the young ones aren't as stupid after all then.

Get over it..I said that to draw you out..it worked.

However my obviously inferior mind can't seem to find any errors in his equations. Care to tell us younglings and straw-men which equation is wrong in your opinion and where exactly he violates the conservation of energy principle?

Honestly, why blather on like that? The problem is you aren't looking at it from a time coherent POV..not because of an "inferior mind". Please refrain from such silly statements.

From the perspective of the energy going into the rear of the cabinet and that coming out the front. The assumption that the front can retain time coherent output even though the energy going in is different between the two cases violates the law of conservation of energy. Remember, reactances are orthogonal to resistors...

Cheers, John

ps..I'll get to your other post monday..I've important things to do right now...honeydew list...

 

[Omicron]

Convienient? Hey, it worked..I was quite surprised it worked as well as it did.

I find it rather difficult to believe you are actually being serious about this.

So, the crossover network knows exactly what to store and what to release, and to do so in a time coherent fashion..?

That's not an argument at all. If you can point to the exact equation that is wrong then please do.

I do not need all that math to see there is no distortion. Call me simple if you want. Indulge me and let us take a look at the system schematic shown at the page you mention:

Notice how in both cases the currents through the speakers (the Rs at the right) are the same? This is no coincidence because your entire argument is built on the fact that they are: after all the only currents we are talking about are the A and the B (or Ihf and Ilf) which individually are the same in both cases. The only difference being the path they flow along before they reach the speakers.

Now John, please PLEASE explain to us this: if the currents through the speakers are exactly the same in both cases then WHERE is this distortion you are talking about? Do the speakers magically sense that the dissipation in the wires is funky and decide not to obey ohm's law any longer? That would be quite the find!

If you cannot answer this very simple question then all the rest is simply irrelevant! But I'm sure you'll again skirt around this issue in your next post and tell me "I don't understand the issue". Well...so be it!

 

[jneutron]

A linear circuit can cause non linear distortion.

It is this fundamental principle that is disputed by John.

Um, nope..Don't put false claims in my mouth.

I'm not exactly sure if he actually understands that his claims are violating this principle

You don't understand the argument.. To the casual observer, it may appear that way, but this is the only path that can be taken to get to the real crux of the matter.

Sorry it's painful for you, but learning is far better than having it spoon fed.

Another thing that is hard to swallow for the electrical engineer is the way John goes about trying to prove his hypothesis. His arguments are always based not on what is going on in the speakers (which is what matters) but on what is going on in the wires between the amplifier and the speaker. John insists on looking at the power losses in the wires when the sound that we perceive is analogous to the current or voltage waveforms of the speakers. To our mind he is looking at the wrong parameter in the wrong place.

Diversion is unbecoming...look it's halley's comet..

That which doesn't make it to the speaker cabinet is a difference. Leseuf confirmed the difference, you agreed with his analysis which confirms the losses are different, but yet both of you believe the speaker will react identically even though they do not receive the same power.

So you really need to figure out how two speakers connected to the same amp, one biwired one not, can produce the exact same output at the exact same time, but yet one receives less power at some instants in time.

It's not that conceptually hard to see, right??

The summarize, if John is really right then he will win himself at least one nobel prize and will undoubtedly enter the pantheon of the greatest minds on the planet. I wish him the best of luck.

Sigh, you need to get off the horse, stop diversionary tactics..and answer the Q...how two speakers given different power vs time, act the same? You agreed with Jim that the power was diff..remember?

I hope this post may give some insight to the casual reader about exactly what this discussion is about.

Only if they ignore the content and stick with your diversion..

I'll give you another hint...we are talking about speakers..and their reaction to arbitrary stimulus..

Cheers, John

ps..what's going on with this site..the page numbering is messin up. Anybody else have the problem??

pps...Kurt, look at Jim's power graphs.. I believe it's on page 2.

 

[Omicron]

So you really need to figure out how two speakers connected to the same amp, one biwired one not, can produce the exact same output at the exact same time, but yet one receives less power at some instants in time.

It's not that conceptually hard to see, right??

We agree that the power losses in the wires look different if you plot them. No argument there.

We do NOT agree that the speakers receive a different power input. THAT is the crux of the matter. The power losses in the wire do NOT reflect on the power received by the speakers. It is trivially easy to see that because the currents through the speakers did not change!

Sigh, you need to get off the horse, stop diversionary tactics..and answer the Q...how two speakers given different power vs time, act the same? You agreed with Jim that the power was diff..remember?

You clearly don't understand what Jim and I are saying. The speakers do not receive different power versus time! Jim is very explicit in this and so am I.

 

[jneutron]

We agree that the power losses in the wires look different if you plot them. No argument there.

Good. I was afraid you'd argue that..

We do NOT agree that the speakers receive a different power input. THAT is the crux of the matter. The power losses in the wire do NOT reflect on the power received by the speakers. It is trivially easy to see that because the currents through the speakers did not change!

When both speaker sets are connected to the same voltage source, and one sees less power at an instant in time than the other (you agree with Jim on that), then the speakers do not see the same power at that instant....

You clearly don't understand what Jim and I are saying. The speakers do not receive different power versus time! Jim is very explicit in this and so am I.

He says they do. He also says the reactances balance that loss equally and opposite, net effect zero.

I've known what your talking about since '74.

You need to re-think the system dynamics..

When you are ready, we can discuss non steady state, which is where all this is going...you missed the hint...

Cheers, John

ps. Excellent dialogue Kurt. Thank you ..see ya monday..

 

[Omicron]

When both speaker sets are connected to the same voltage source, and one sees less power at an instant in time than the other (you agree with Jim on that), then the speakers do not see the same power at that instant....

This is how I see it:

- The power in the speakers is a GIVEN in your experiment and determined solely by the CURRENT going through them. The current is the same in all the cases you presented hence the power is the same AT ANY INSTANT IN TIME.

- The power output by the amplifier is the same.

- The power dissipated in the wires is different (instantaneously speaking). True. Ergo someplace else in the circuit is compensating for this. We both got this part wrong (I blamed the amp, which is wrong) but Jim got it right in his analysis:

- The only things left in the circuit that can compensate are the filters. Weird you say? Not really as the filters are required to set up the conditions you specify. They are constrained on one side by the speakers (who's power dissipation is a given and fixed) and the wire dissipation on the other hand. They do not miraculously do the right thing, their behavior is imposed on them and simply a consequence of the circuit topology.

- There is no violation of energy anywhere in this. At any instant:

Pamp = Pwire + Pfilters + Pspeaker

Note however that Pfilters can be negative and must average out to 0 since they are reactive elements. This quite elegantly also provides us with an explanation as to why the 2AB component has to average out to 0 as well (as you have pointed out it does).

 

[jneutron]

This is how I see it:

- The power in the speakers is a GIVEN in your experiment and determined solely by the CURRENT going through them. The current is the same in all the cases you presented hence the power is the same AT ANY INSTANT IN TIME.

Actually, no.

Examine the case of both speakers being driven by the SAME amplifier. That is the initial condition I had set, in order to eliminate the variable of the amp.

Both speaker sets (at the amp terminals) START with the same voltage. But yet, the monowire set receives power that is modulated by the addition of the 2AB component (recall this is what I first stated, Jim agreed, and you agree with Jim)

- The power output by the amplifier is the same.

Umm, again, no. This is your assumption. The fact that one wireset is dissipating more power (or less) at any instant, means that one speaker set is not receiving identical power (in time) as the other one (my assertion).

- The power dissipated in the wires is different (instantaneously speaking). True. Ergo someplace else in the circuit is compensating for this. We both got this part wrong (I blamed the amp, which is wrong) but Jim got it right in his analysis:

He did? Where? How does an orthogonal (reactive) component compensate instant to instant, that of a dissipative element?? Remember, since the amp can only look at the speaker through the wires, and both wires are dissipating DIFFERENTLY, how can the speaker terminals be exactly the same??

- The only things left in the circuit that can compensate are the filters. Weird you say? Not really as the filters are required to set up the conditions you specify. They are constrained on one side by the speakers (who's power dissipation is a given and fixed) and the wire dissipation on the other hand. They do not miraculously do the right thing, their behavior is imposed on them and simply a consequence of the circuit topology.

Who said the speakers do the same thing???? Not I...that would be an assumption. Since the wires dissipate energy differently, and the reactive components do not dissipate at all, the balance is up to the speakers. Time shifted energy is THE CRUX OF THE ISSUE. Not average power. All heck breaks loose once we leave steady state..(hint)..

- There is no violation of energy anywhere in this. At any instant:

Pamp = Pwire + Pfilters + Pspeaker

Since the amp voltage is equal in both cases, there is a difference because the wires dissipate differently.. The assumption that the speakers act exactly the same in time violates conservation of energy..

Note however that Pfilters can be negative and must average out to 0 since they are reactive elements. This quite elegantly also provides us with an explanation as to why the 2AB component has to average out to 0 as well (as you have pointed out it does).

Umm...there is no such thing as negative power..I assume you meant storage vs release..and they both act 90 degrees out..

The 2AB power envelope, which does indeed has a negative component, is an anomoly, a construct that cannot exist standalone..it can only exist as a modulation of the A squared plus B squared entities...they always are equal to or greater than the 2AB component. Otherwise the system would cool down...


The 2AB component has a net zero integral. Hence my concern that it cannot be seen by a math package that looks for integrated power (that would be an FFT).

Nice try though....very well thought..

It's been a pleasure reading and responding to you..do not quit..


Cheers, John

ps..I'm glad I gave you the link to Jims webpage..it allows a commonality of discussion..

 

[Omicron]

Actually, no.

Examine the case of both speakers being driven by the SAME amplifier. That is the initial condition I had set, in order to eliminate the variable of the amp.

Both speaker sets (at the amp terminals) START with the same voltage. But yet, the monowire set receives power that is modulated by the addition of the 2AB component (recall this is what I first stated, Jim agreed, and you agree with Jim)

You cannot think about power in this way. The speakers do not "receive" power. They receive voltage (or current) which makes them dissipate power. The power they dissipate is dictated by the simple relation Pspeaker = Sq(Ispeaker)*Rspeaker. Simple as that.

If you argue that they would dissipate different power then by consequence the current trough them would have to be different as well. And that contradicts the basic assumption of your experiment, i.e. only currents A and B are flowing in the system.

How does an orthogonal (reactive) component compensate instant to instant, that of a dissipative element?? Remember, since the amp can only look at the speaker through the wires, and both wires are dissipating DIFFERENTLY, how can the speaker terminals be exactly the same??

The filters are a necessary item to set up the conditions of your experiment (i.e. split A and B apart perfectly). Note also that in real life no filter can behave the way you assumed (being infinitely steep). So the filters you use aren't exactly your regular basic reactances. Why are they able to exactly compensate? Simply because the circuit you created doesn't leave them any other choice courtesy of the law of conservation of energy. The math of Jim is spot on.

The more I think of it the more I am convinced the issue would become much clearer to you if you would abandon the idea of the "perfect" filters and actually redo the maths with a real capacitor and a real inductor in the circuit. The split between A and B will not be perfect in that case and 2AB type components will also start to pop up in the bi-wire case. The perfectly steep filters you assume now unwittingly introduce infinities into the circuit that muddle the issue.

Umm...there is no such thing as negative power..I assume you meant storage vs release..and they both act 90 degrees out..

Off course there is if you're talking about instantaneous power in the time domain (which you insist on doing). All reactive elements will show positive (storing energy) and negative (releasing energy) instantaneous power. Because they cannot dissipate energy the power has to average out to zero over time for any purely reactive element.

The 2AB component has a net zero integral. Hence my concern that it cannot be seen by a math package that looks for integrated power (that would be an FFT).

A term 2AB doesn't sound like a subtle distortion but quite a big one. Don't you think we should easily be able to see it in the time domain using a simple analogue oscilloscope?

 

[Omicron]

The 2AB component has a net zero integral. Hence my concern that it cannot be seen by a math package that looks for integrated power (that would be an FFT).

A little practical experiment that just popped into my mind:

If you make the wire resistance much much larger than the resistance of the speakers, then you can make the 2AB power loss component so large that it has the same order of magnitude as the power dissipated in the speakers. Right?

In that case the proposed distortion would have to be huge because, in your reasoning, the speakers have to compensate and the compensation is in the same order of magnitude as the undistorted power they where putting out in the first place. Distortion so huge would be easily heard or seen on an analogue oscilloscope. If it existed...