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

[E-Stat]

I cannot prove any scenario, but I cannot disprove it. You cannot prove or disprove it, either!

That's why I don't begin with unsupported assumptions.

I am a speaker manufacturer.

Do your products directly compete with Avalon, Revel, Dynaudio, Nola, Kharma, etc.?

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!

Your commentary is better known as speculation. Debating such is an utter waste of time.

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

Then again, I may be asking the correct question. My opinions are devoid of conspiracy theories.

rw

[jneutron]

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

Yup. Suprising how slow the little suckers move, yes?

Actually, the electrical signals travel at a prop velocity defined by the media. For free space, it is the speed of light.

For cables, it is V = 1/sqr(LC)

For free space, it is V = c/sqr(mu epsilon).

Unless of course, you revisit that radio-electronics article where the guy claimed faster than light propagation..

Cheers, John

[kexodusc]

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.

One signal perhaps, but I was under the impresssion it would have multiple frequencies simultaneously?
Perhaps I'm missing something trivial to you folks. What am I missing exactly. I play an 80 Hz tone, I assume 80 Hz signal travels the wire, and the speakers produce the 80 Hz tone. Likewise with the ground loop effect at 60 Hz, I hear a 60 Hz tone.

The way I understand a simple microphone, air pressure is converted to votlage waveforms which convert audio-frequency air pressure waves into corresponding voltage waveforms. The exact makeup of these frequencies in the voltage signal is dependent on the sound being reproduced. If the sound waves consist of a 60 Hz tone, the voltage waveform will likewise be a sine wave 60 Hz?. If the sound wave is composed of several notes, say, a chord, then waveform produced by the mic will consist of those frequencies mixed together.

So a harp and bass play their highest and lowest notes, respetively, would not the 2 separate frequencies corresponding to those notes travel the speaker wire simultaneously?

This thinking was the basis for my assumption...perhaps more simply put, how else could a speaker simultaneously output the sound a guitar, singer, bass, and drums all make at the same time?

[Resident Loser]

One signal perhaps, but I was under the impresssion it would have multiple frequencies simultaneously?...
This thinking was the basis for my assumption...perhaps more simply put, how else could a speaker simultaneously output the sound a guitar, singer, bass, and drums all make at the same time?

...prezackly...

As I see it, all freqs travel on all wires (except for the returns, which are post-crossover)...It's at that Xover that certain frequencies are allowed to pass (hence bandpass) or not...IMO biwiring simply eliminates that relatively innocuous jumper and trades it for x-amount of additional wire, adding series resistance and capacitance and doubling the target for the hash...If there is a resultant change in sound, it would seem to be due to the changes effected by that additional wiring on the crossovers' parameters...This happens whether the Xover is located in the loudspeaker cabinet or remotely i.e. closer to the amplifiers outputs.

jimHJJ(...I may be stupid, but I just don't get it...)

[kexodusc]

...prezackly...

As I see it, all freqs travel on all wires (except for the returns, which are post-crossover)...It's at that Xover that certain frequencies are allowed to pass (hence bandpass) or not...IMO biwiring simply eliminates that relatively innocuous jumper and trades it for x-amount of additional wire, adding series resistance and capacitance and doubling the target for the hash...If there is a resultant change in sound, it would seem to be due to the changes effected by that additional wiring on the crossovers' parameters...This happens whether the Xover is located in the loudspeaker cabinet or remotely i.e. closer to the amplifiers outputs.

jimHJJ(...I may be stupid, but I just don't get it...)

Exactly. The only thing siginificant I see biwiring changing is the current in the wires before the speaker terminals. Which then feed the the HP and LP filters. But, wouldn't the current through the crossover components be pretty much the same in both setups (minus affects fromJneutron's 0-1.48% or power losses)?
Gosh, I've seen some speakers that have only 1 terminal, but then inside the single lead between terminal and crossover splits into two runs of 18 gauge wire, one to the LP, one to the HP. Wouldn't that be the same as "internal biwiring"...man, that's speaker marketing!

[Dusty Chalk]

One signal perhaps, but I was under the impresssion it would have multiple frequencies simultaneously?
Perhaps I'm missing something trivial to you folks. What am I missing exactly. I play an 80 Hz tone, I assume 80 Hz signal travels the wire, and the speakers produce the 80 Hz tone. Likewise with the ground loop effect at 60 Hz, I hear a 60 Hz tone.

The way I understand a simple microphone, air pressure is converted to votlage waveforms which convert audio-frequency air pressure waves into corresponding voltage waveforms. The exact makeup of these frequencies in the voltage signal is dependent on the sound being reproduced. If the sound waves consist of a 60 Hz tone, the voltage waveform will likewise be a sine wave 60 Hz?. If the sound wave is composed of several notes, say, a chord, then waveform produced by the mic will consist of those frequencies mixed together.

So a harp and bass play their highest and lowest notes, respetively, would not the 2 separate frequencies corresponding to those notes travel the speaker wire simultaneously?

This thinking was the basis for my assumption...perhaps more simply put, how else could a speaker simultaneously output the sound a guitar, singer, bass, and drums all make at the same time?

All your suppositions are correct. The frequencies travel all together at the same time.

Are you familiar with Visio, or any other graphic editor? You know how you can select multiple objects and group them? After that, you treat the resultant group as one picture. It's the same with the audio signal. As far as the electricity is concerned (and localized air pressure, too), there aren't multiple frequencies, there is one signal. Think of a sawtooth or pulse wave (or a clarinet note or the human voice) -- it's made up of multiple frequencies, but what travels down the wire is a sawtooth or pulse wave.

This divvying up of the audio spectrum into frequencies is a model -- just another way of looking at things. IMHO, the model was beginning to fall apart -- it was turning into a bad way of looking at things -- hence why I spoke up.

[jneutron]

Are you familiar with Visio, or any other graphic editor? You know how you can select multiple objects and group them? After that, you treat the resultant group as one picture. It's the same with the audio signal..

Ah, my friend, this is where you are incorrect...

While voltage and current will do such (add linearly), the dissipations within the wire do not behave that way. Two one amp currents added will dissipate four times the amount of power, not two..to extend your example, if you select two square objects and group them, the expectation is an area twice as large, not four as power dissipation does.

This divvying up of the audio spectrum into frequencies is a model -- just another way of looking at things. IMHO, the model was beginning to fall apart -- it was turning into a bad way of looking at things -- hence why I spoke up.

Who's model is beginnng to fall apart?

Cheers, John

[Resident Loser]

All your suppositions are correct. The frequencies travel all together at the same time.

Are you familiar with Visio, or any other graphic editor? You know how you can select multiple objects and group them? After that, you treat the resultant group as one picture. It's the same with the audio signal. As far as the electricity is concerned (and localized air pressure, too), there aren't multiple frequencies, there is one signal. Think of a sawtooth or pulse wave (or a clarinet note or the human voice) -- it's made up of multiple frequencies, but what travels down the wire is a sawtooth or pulse wave.

This divvying up of the audio spectrum into frequencies is a model -- just another way of looking at things. IMHO, the model was beginning to fall apart -- it was turning into a bad way of looking at things -- hence why I spoke up.

...a complex waveform is a complex waveform, that's a given...but that's not the question...it's basically why would biwiring cause all the required ducks to line up in a row any more sucessfully than that jumper between those nearly-now-ubiquitous biwire terminals on the rear of speaker cabinets...it's the crossover that does the deed whether it's fed by one pair or two...

The fundamental frequency may be passed to the lo-freq driver while the overtones related to it go through the hi-freq passband...if anything, and with certain scenarios, I would venture a guess there might be some sort of time lag induced by the extra wiring of a biwiring scheme, a smearing if you will...Some people also seem to like the "warmth" of tubed electronics, there might be some correlation...Does a square wave look the same going out as it did going in?

jimHJJ(...does biwiring make the signal all warm and fuzzy therefore more amenable to some?...)

[jneutron]

... I would venture a guess there might be some sort of time lag induced by the extra wiring of a biwiring scheme, a smearing if you will...

Smearing..sheesh

Where do you get this stuff???huh??

Go home, prep the bird..fuggetabout dis stuff..

Happy thanksgiving..

Cheers, John

[kexodusc]

This divvying up of the audio spectrum into frequencies is a model -- just another way of looking at things. IMHO, the model was beginning to fall apart -- it was turning into a bad way of looking at things -- hence why I spoke up.

I see where you're coming from. My line of thinking kinda needs for the model to consider it though - the model was simple, and fine for demonstration. In practical usuage, there's not a simple 8 ohm resistor at the end of each wire, but rather different filters and drivers with different reactances...so the currents in each wire will depend on the impedance of the connected drivers at the given frequencies. Thus, the net power loss differences would depend on the frequencies as well. A bad way of looking at things? Maybe. But if this is what happens in practice, I'm not sure we can call it bad or just ignore it because it makes for a complicated model.
That kind of selective attention is what speaker companies do when they present consumers with that "nominal impedance" spec. Personally, I like to know how low the impedance dips when I build a speaker, and where. It sure makes designing a good crossover a lot less complicated.

All this to say that if biwiring makes an audible, measurable difference of between 1.48%, and 0% (or course we're omitting other measurable differences if there are any), and most likely a much smaller range, there's definitely reason to question the pracitcal benefits of biwiring. At any rate, the small 1.48% difference would be consistent with what my ears have told me...insignificant differences, too small to reliably develop a preference for. Then again, the cost of adding a bi-wiring option is pretty negligible. Doesn't hurt to try. And we still haven't been able to conclude if one is better. Just that they can be shown to be very slightly different.

[Resident Loser]

Smearing..sheesh

Where do you get this stuff???huh??

Go home, prep the bird..fuggetabout dis stuff..

Happy thanksgiving..

Cheers, John

...I musta' confused my bagel and cream cheese with the subject at hand...

Bird-prep is on the morrow, starting at about 6AM...tonight it's some of the sides...

jimHJJ(...but I'll hafta check that on that smearing thing...I could swear it was in one of the handouts when I got my audiophool certification from the IHF...)

P>S> HAPPY THANKSGIVING everyone!!!

[jneutron]

...I musta' confused my bagel and cream cheese with the subject at hand...

Ah, that almost explains it...buuut, was the smearing clockwise...or counterclockwise??? (I didn't forget the mustard.)


A note to the site administrator:

110 posts in this thread alone, whereas the entire month of posts in this forum that are visible when arriving is 88.

And the discussion varies from audible through actual technical discussion.

Tell me again why you have the lab?

Perhaps it's time to revisit the previous decision?

Happy thanksgiving.

Cheers, John

[jneutron]

All this to say that if biwiring makes an audible, measurable difference of between 1.48%, and 0% (or course we're omitting other measurable differences if there are any), and most likely a much smaller range, there's definitely reason to question the pracitcal benefits of biwiring. At any rate, the small 1.48% difference would be consistent with what my ears have told me...insignificant differences, too small to reliably develop a preference for.

Do not get hung up with that 1.48% number. It was derived from a specific model, that of 8 ohms and 120 milliohms of loop resistance.

Somebody should have spotted the relationship between the series resistance, the load, and the percentage...I am shocked and dismayed that nobody spotted it..

The maximum monowire error turns out to be the cable loop resistance divided by the load impedance..

.120/8 = .015, or 1.5%

If your impedance were to drop to 4 ohms, the error is 3%.

If you run 25 feet of #18awg into a 4 ohm load???

6.5 mOhm per foot times 2 times 25...325 milliohms.

.325/4 = 8.125%

8%...small potatoes..Hey guys, let me know when the error component starts to approach audibility, ok??

In the meantime, somebody explain to me why this stuff hasn't been measured??
(TIC, I know why) (I think)

Cheers, John

[Geoffcin]

A note to the site administrator:

110 posts in this thread alone, whereas the entire month of posts in this forum that are visible when arriving is 88.

And the discussion varies from audible through actual technical discussion.

Tell me again why you have the lab?

Perhaps it's time to revisit the previous decision?

Happy thanksgiving.

Cheers, John

Think of it as out own little Guantanimo....

Nice to see you and RL getting along again.

ps. that makes 114 posts!

[hermanv]

Perhaps a simple poll would be useful here.

1. Do you Bi-wire your speakers?
2. Have you ever tried it?
3. Did you notice any difference?
4. Please catagorize your system:
   
   1. Normal (Your neighbors rarely comment)
   2. Exotic (Your neighbors say wow!)
   3. Insane (Your neighbors question your ability to make financial decisions)

[kexodusc]

Perhaps a simple poll would be useful here.
Do you Bi-wire your speakers?

No

Have you ever tried it?

Yes

Did you notice any difference?

No

Please catagorize your system:
Normal (Your neighbors rarely comment)
Exotic (Your neighbors say wow!)
Insane (Your neighbors question your ability to make financial decisions)

My neighbors say wow to the 6 speaker/receiver combos in Sears. They rarely comment on mine. That make my system normal?

[hermanv]

My neighbors say wow to the 6 speaker/receiver combos in Sears. They rarely comment on mine. That make my system normal?

Since you are following this thread and posting on this forum any claims of normalcy are automatically suspect.

[Mike Anderson]

Do you Bi-wire your speakers?

Yes.

Have you ever tried it?

Obviously yes.

Did you notice any difference?

No - it takes too long to switch out the cables to make a decent comparison. That doesn't mean there's no effect, only that it is comparatively subtle, if there is one.

Please catagorize your system:

Exotic (Your neighbors say wow!)

[hermanv]

Just for the record, if perhaps I wasn't clear.

Yes
Yes
Yes
Exotic

[jneutron]

Think of it as out own little Guantanimo....

He he..

Nice to see you and RL getting along again.

Que??

I was unaware that we were not getting along.. I believe you may be thinking about somebody else.

Hey Resident Loser, do you have any clue what he is referring to???

Cheers, John

[Dusty Chalk]

Ah, my friend, this is where you are incorrect...

While voltage and current will do such (add linearly), the dissipations within the wire do not behave that way. Two one amp currents added will dissipate four times the amount of power, not two..to extend your example, if you select two square objects and group them, the expectation is an area twice as large, not four as power dissipation does.

I wasn't talking about adding signals -- I was talking about thinking of a single signal as multiple frequencies added up. That model.

Who's model is beginnng to fall apart?

No need to get condescending -- I never stated my model, and have, for the most part, stayed out of this discussion. So certainly the implication -- that my model is falling apart -- is completely false.

[jneutron]

I wasn't talking about adding signals -- I was talking about thinking of a single signal as multiple frequencies added up. That model.No need to get condescending -- I never stated my model, and have, for the most part, stayed out of this discussion. So certainly the implication -- that my model is falling apart -- is completely false.

I recommend you go back and read my post. This time, re-read YOUR statement, and then re-read my response to your statment.

Here is your statement again..
Quote:

Originally Posted by Dusty Chalk
This divvying up of the audio spectrum into frequencies is a model -- just another way of looking at things. IMHO, the model was beginning to fall apart -- it was turning into a bad way of looking at things -- hence why I spoke up.

And here is my statement:

Who's model is beginnng to fall apart?

Now, within the context of your statement, and my question, how does one read condescension into it?.. I have asked a simple question....who's model are you referring to when you said ""the model was beginning to fall apart""?

It is a very simple question, and one asked to reflect my confusion as to what you were referring.

Sometimes a question is...simply a question.

Cheers, John

[Resident Loser]

...Que?? I was unaware that we were not getting along.. I believe you may be thinking about somebody else.

Hey Resident Loser, do you have any clue what he is referring to???

Cheers, John

...mention it...not a one...Heck, we even have interesting and friendly non-audio banter...

jimHJJ(...I think I got turkey poisoning!!!...)

[Resident Loser]

...no, because I can't...only one set of terms...in fact come to think of it, I don't have a Xover...although back in the 80s, I bought a set of Polk Cobras on an impulse while looking for some DtoDs @ my local hi-fi emporium...they looked cool, but no diff as far as I could tell...although they may have been the reason my amp went poooof! 10ga. jacketed PA wiring afterwards, with no probs...

And some friends and relatives think $5k worth of gear is certifiable behavior...

jimHJJ(...seemed about right at the time...)

[Dusty Chalk]

Okay, I misunderstood your sincere question. I read it as "Now who's model is falling apart." I apologize. Spent > 31 hours driving this weekend, still a little cranky.

And I don't see that it's important who's model it is -- I was just criticizing the model (I try very hard to leave ego out of arguments like this). If you read kexodusc's post (#103), that last post was just trying to answer that question. The fundamental question, "how does a speaker output two sounds at the same time", is the one I tried to answer. From the speaker's perspective, it's not two sounds -- they've already been mixed together at the mixing desk, and are now one sound.

And yes, I'm not saying that model does not have its uses -- absolutely it does! When you're designing crossovers, it's absolutely the only way to go, to think of LRC circuits as high-, low- and band-pass filters and so on. I'm just saying, if one is stumbling across the concept of how two signals can flow across one wire, then maybe it's time to take a step back and reevaluate. You might even come to the conclusion that this is still the appropriate model (especially if you're analyzing it to the level of detail where the skin effect comes into play). After all, I said beginning to fall apart, not that it had fallen apart completely already.