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  1. #26
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    Quote Originally Posted by E-Stat
    Omniscient, are we?
    rw
    Don't know..gotta look that up. It certainly isn't in my copy of Jackson.

    Edit: ah, I realized a better word than Omniscient.. Historian. As in, so far, to date, I've not seen an explanation which holds water. Those who explain why it does either misconstrue existing concepts, extend out hearing ability far beyond reasonable, or make stuff up as they go along. Reasons why it can't work have not historically hit the target either..

    So, no, not Omniscient. (end of edit)

    I can't believe nobody's followed up on the dissipation angle, it's just so darn simple. Sheesh, I posted it what, two years ago?
    Quote Originally Posted by E-Stat
    Skeptic/Soundmind's attempted derogatory term is "dressing screens". rw
    Ah yes, dressing screens..well, they probably still need rear firing tweets.. Take it from me...my coffee cup has rear firing tweets, and the coffee tastes so much better..

    Quote Originally Posted by E-Stat
    Aside from some rain, things are doing well here in AR. Negativity? I rather appreciate it when knowledgeable folks correct the simple conclusions made by armchair audio engineers. rw
    When I find someone who is knowledgeable, I'll send them here..till then, all ya gots is me..I post in between sweeping the floors and cleaning the bowls..

    Cheers, John
    Last edited by jneutron; 11-15-2006 at 09:12 AM.

  2. #27
    Music Junkie E-Stat's Avatar
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    Quote Originally Posted by jneutron
    Ah yes, dressing screens..well, they probably still need rear firing tweets..
    My big a$$ dipoles have thirty square feet of 'em!

    While "rear firing tweeters" was the title of the post, what really floats SM's boat is spraying HF at the ceiling using three tweets crossed over at 6 khz. Yes, you heard me correctly.

    rw

  3. #28
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    Quote Originally Posted by E-Stat
    My big a$$ dipoles have thirty square feet of 'em!

    While "rear firing tweeters" was the title of the post, what really floats SM's boat is spraying HF at the ceiling using three tweets crossed over at 6 khz. Yes, you heard me correctly.

    rw
    Ah. Honestly, when I see both of your monikers, I have little desire to delve into the sub thread...again, a historical consideration, nothing more..

    Cheers, John

  4. #29
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    Good one!!!

    Quote Originally Posted by jneutron
    Oh jeeze, I ended up in the wrong place..no wonder there were new posts here...Yourself??
    Other than trying to keep neighbors and their relatives, contractors, tenants and other non-descript associates thereof from using my driveway as their own private passage to India, not much...'ceptin leaves, which I don't mind so much...I'm fond of mindless endeavors, like visiting audio sites...

    Replaced the muffler and tail-pipe on my Jeep...heads were a-turnin' and it wasn't because I'd won a concours d'elegance...yet another use for the ol' Sawzall...what a wonderful, constructively destructive tool! Steel casement windows, tree limbs, tail-pipes...do it's uses never end?

    A new Diehard, serpentine drive belt, and 6qts of 10W-30 Mobil1 and I'ze winterized...

    The high point was baking a coupla' loaves of bread...I'm gettin' purty good at it...

    Also managed to get a few CDs at the Tower Records near Roosevelt Field...sad, another old name bites the dust...

    jimHJJ(...good luck with the shop...)
    Hello, I'm a misanthrope...don't ask me why, just take a good look around.

    "Men would rather believe than know" -Sociobiology: The New Synthesis by Edward O. Wilson

    "The great masses of the people...will more easily fall victims to a great lie than to a small one" -Adolph Hitler

    "We are never deceived, we deceive ourselves" -Goethe

    If you repeat a lie often enough, some will believe it to be the truth...

  5. #30
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    Quote Originally Posted by Resident Loser
    The high point was baking a coupla' loaves of bread...I'm gettin' purty good at it...
    Bein gluten-intolerant, I can understand that. I'm gonna buy one of dem bread makin thingy's, a friend made some and holy mackeral, do I miss bread..there's some awful nice wheat free bread mixes out there which mimic reglar bread quite well...without the consequences.

    Quote Originally Posted by Resident Loser
    Also managed to get a few CDs at the Tower Records near Roosevelt Field...sad, another old name bites the dust...

    jimHJJ(...good luck with the shop...)
    You near there, eh? I'm goin to get the lcd at 6th ave electronics I believe.

    Sawsalls are great, aren't they?

    Yah, havin a workbench for the woodworking is something I miss terribly. This time, I'm gonna add dust collection to it.

    Cheers, John

  6. #31
    Forum Regular hermanv's Avatar
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    In ceiling speaks? In ceiling speaks !#**\\!

    I recommend banishment from the site.

    Will you at least bi-wire them?
    Herman;

    My stuff:
    Olive Musica/transport and server
    Mark Levinson No.360S D to A
    Passive pre (homemade; Shallco, Vishay, Cardas wire/connectors)
    Cardas Golden Presence IC
    Pass Labs X250
    Martin Logan ReQuests.

  7. #32
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    Quote Originally Posted by hermanv
    In ceiling speaks? In ceiling speaks !#**\\!

    I recommend banishment from the site.

    Will you at least bi-wire them?
    No.

    (Think Richard Crenna in that comedy spoof of first blood..)

    Each is fed by about 100 feet of 14 guage...

    That 14 guage is bundled with 7 cat5e cables, two thermostat cables, 1 75 ohm cable, two 1/2 inch copper pipes, and comes through the same stud bay as 2 romex runs.

    Each speak is five inch.

    Each has a 3/4 inch cone tweet.

    Each are placed asymmetrically in the ceiling.

    The x'overs are stock.

    In the basement, the wires are stripped and twisted to the feeds from the RECEIVER. (note, I did remember to connect red to red, black to black..)

    The connections are dangling from a floor joist.

    They are dangling two feet from a central air unit.

    The cd's are burned copies made with mp3 at 128..

    Had enough?? Gonna spill your guts?? Hmmm??

    They met the need.

    Cheers, John

    Almost forgot..Bdrm, kit, and living room speaks all tie into a pushbutton selector box with those strip and push type connections, and most of the wire conductors are actually in the connector.. (ewwww)

  8. #33
    Forum Regular hermanv's Avatar
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    Getting back to the discussion:

    The goal is the "best" possible sound from a system. Best of course is a subjective description, but only I have to be pleased with my own end results.

    First I need to back up a bit. My audiophile friend and I decided to build our own speakers because we just couldn't afford those commercial ones we liked. It took 7 years and $7,500 (assuming free labor), but we have built some three way speakers that are as good or better than any speakers we have heard. We are currently working on the second set for me, most parts were purchased in sets of 4 so most of the money has been spent.

    All of this is relevant because of the things we learned about wiring. As the speakers were being developed and the quality gradually improved, we learned that exotic and expensive passive parts (silver coils, tin foil and polypropylene capacitors) sounded considerably better than the cheaper mass market parts. We ended up replacing all the wires and the rest of an already decent system with better electronics and cables to enable the drivers to perform to their fullest.

    Now finally, the speaker wiring: We tried all kinds of arrangements with several brands of specialty wires. In the end we found a couple of trueisms. 1. A larger gauge always sounded better. 2. Silver was better than copper but the difference was inaudible (to us) on the woofer. In playing around with various configurations we found a winner.

    We moved the crossover to be right at the back of the power amp and ran longer seperate wires to each driver. We used 9.5 AWG Cardas copper for the woofer, it's fairly cheap and nice and big. We used 5 wires of 11.5 AWG arranged in a low inductance ribbon for the Mid, silver sounded a bit cleaner but we just couldn't afford that much silver (about 9 AWG aggregate) and finally becase the current and power are low we were able to use 5 silver 21 gauge wires for the tweet also arranged in a low inductance ribbon (about 17.5 gauge aggregate). All the wire was made by Cardas, whose stories read better than most. All the wires were Teflon insulated and (damn it) sounded better when they were raised off the floor.

    We concluded that at the extremes of audio performance tiny details are audible and make a difference. Remember that a CD has a dynamic range of 96dB, that means the smallest signal being captured is very, very small so effects that do not show up in first order measurements can easily influence the end result. Put another way, if you are listening at around 4 watts average level which is near normal active listening levels, then the smallest signal would be around 600 microwatts perhaps smaller if you allow for over sampling.
    Herman;

    My stuff:
    Olive Musica/transport and server
    Mark Levinson No.360S D to A
    Passive pre (homemade; Shallco, Vishay, Cardas wire/connectors)
    Cardas Golden Presence IC
    Pass Labs X250
    Martin Logan ReQuests.

  9. #34
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    You state "low inductance" for your various wires.

    What were the measured LCR's for them?

    Cheers, John

  10. #35
    DIY Dude poneal's Avatar
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    OK, this is my last post on this topic as it seems to be

    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

  11. #36
    DIY Dude poneal's Avatar
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    Quote Originally Posted by jneutron
    That would be incorrect.


    Nothing you have posted yet supports that assertion.

    Cheers, John

    OK, one last time for the slow learner. In bi-wiring you have a single wire just like you do without bi-wiring from the amp. At the terminals, you make some jumpers and plug them into the other terminal. Same signal, same amp, same everything except a smidgen of added wire. The signal does not get changed until it reaches the passive components in the xover. The woofer gets the same signal as the tweeter, the tweeter the same as the woofer. The xover is what filters out the highs or lows. That's all there is to it. Nothing magical, nothing complicated, it's just the way it works. One more time, the signal doesn't get changed until it hits the passives in the network. You still have the same old problems as with reg. wiring. If your woof takes up the full 100watts then whatever is left over goes to the tweeter and mids. Probably distorted. One way to solve this is bi-AMPING but bi-wiring is nothing. I mean come on. Look at the diagram. All they did was separte the xovers. I've built designs like this. I don't use it for bi-wiring but it sure does help out when measuring. Hook one xover up to one and the other to the other and then all you have to do to measure the other is to switch the speaker wire. This is not complicated, it's so simplistic, oh nevermind.

    Paul

  12. #37
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    Quote Originally Posted by poneal
    getting a little heated and opinions are coming in.Paul
    Heated??? Where? What thread are you reading?

    Quote Originally Posted by poneal
    I base mine of facts.
    No, actually you haven't

    You have only stated opinions, and now, you link to the opinion of others.

    Go through Jim's calculations, and find me where he calculates the difference in dissipation between biwiring and normal.

    Quote Originally Posted by poneal
    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.
    Well, where's the wire dissipation component??

    If you wish to explain to us why biwiring is not effective, then you must come up with something better than what you have posted. You're not floatin my boat.

    Quote Originally Posted by poneal
    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
    Silly.

    If you wish to "get it, just ask. I would be happy to explain what you are missing.

    If you just want to slap and run, do so. You won't learn anything that way, however.

    Now, pay attention.

    10 feet #14 awg, 6 mOhms per foot, 60 milliohms total.

    Two sets connectors, 15 milliohms per contact, another 60 milliohms...total insertion, .12 ohms.

    Now, single wire to crossover...two signals...lets make the math easy...8 ohms. 4 amps peak is 16 times 8, or 128 watts peak.

    now, two signals...4 amps bass, 4 for highs. When both signals are at peak current, wire sees 8 amperes. Losses in the wire, I squared R, 64 times .120, or 7.68 watts dissipative loss in the wires.

    Now, seperate them...each wire sees 4 amps peak..I squared R for each wire peaks at 1.92 watts....times 2, is 3.84 watts.

    So, single wire has twice the peak loss as a pair of the same resistance. The most important aspect is not the total power loss, but how it happens. The peak loss is a function of the multiplication of the two currents, not summation as biwiring does. And the difference is 3.8 watts out of a sum of 256, or 1.48% of the total..can you hear 1.48 % distortion??Hmmm?

    I could post the equations, I could post the graphs....but from your demeanor, I fear I would be pissin in the wind. You seem not to want to learn..

    Perhaps I misread you?? If so, I apologize...if not, take it elsewhere..It gets tiring explaining the simple stuff to those who don't care..

    Cheers, John

  13. #38
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    Quote Originally Posted by poneal
    OK, one last time for the slow learner.
    Paul
    Paul, you've no idea. I'm being gentle..

    Quote Originally Posted by poneal
    This is not complicated, it's so simplistic, oh nevermind.Paul
    Read my last post. When you are ready, ask questions.

    You seem to believe that others do not know what you are talking about..Stick around, you'll get over that quickly.

    Oh, btw..I've never heard the difference between regular and biwiring...simply because it is of no concern to me. However, what you've said so far certainly doesn't prove your point.


    Cheers, John

    Ps..I've attached a nice little graph for you to think of..
    Dark blue is the dissipation envelope of the lows.
    Magenta is the dissipation envelope of the highs.
    Yellow is the summation of the two, this is biwire dissipation.
    Light blue is the dissipation envelope of both signals when they are in one wire.
    Brown is the dissipation discrepancy between mono and biwire.
    Notice it is not zero??
    Notice it goes negative??
    It is a class of signals which cannot be viewed by an FFT, as it is a zero power signal.
    Buuuut, it's there for all the world to see..

    Questions? Or, are you still gonna call me a slow learner..
    Attached Thumbnails Attached Thumbnails Bi-wiring The question that can't be answered?-2ab-picture.jpg  
    Last edited by jneutron; 11-15-2006 at 01:53 PM.

  14. #39
    Forum Regular hermanv's Avatar
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    Hi poneal;

    There is some confusion, (from your post #35), in the bi-wire scheme there is no jumper at the speaker ends. Although doubling up the number of wires with the jumpers may help, that doesn't seperate the signal currents as a conventional bi-wire scheme does. In following your own link to end the author proposes and supports that bi-wiring does make a small mathematical diffenence. Small differences is what we are talking about, the link you chose doesn't seem to support your own conclusions.

    Hi jneutron;

    We did measure the inductace, it was a while ago and I no longer remember the answer something in the nanohenries per foot probably. As far as I know the ribbon (flat, side by side) configuration (return, hot, return, hot, return) gives the lowest practical inductance given some physical space considerations.
    Herman;

    My stuff:
    Olive Musica/transport and server
    Mark Levinson No.360S D to A
    Passive pre (homemade; Shallco, Vishay, Cardas wire/connectors)
    Cardas Golden Presence IC
    Pass Labs X250
    Martin Logan ReQuests.

  15. #40
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    Quote Originally Posted by hermanv
    Hi jneutron;

    We did measure the inductace, it was a while ago and I no longer remember the answer something in the nanohenries per foot probably. As far as I know the ribbon (flat, side by side) configuration (return, hot, return, hot, return) gives the lowest practical inductance given some physical space considerations.
    Ah, tis a shame..

    It would have been nice to calculate the effective dielectric constant and characteristic impedance from your geometry.

    LC = 1034 EDC, L in nH per foot, C in pf per foot...

    Z = sqr(L/C)

    Cheers, John

  16. #41
    DIY Dude poneal's Avatar
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    Maybe I was a little sarcastic....

    Quote Originally Posted by jneutron
    Paul, you've no idea. I'm being gentle..



    Read my last post. When you are ready, ask questions.

    You seem to believe that others do not know what you are talking about..Stick around, you'll get over that quickly.

    Oh, btw..I've never heard the difference between regular and biwiring...simply because it is of no concern to me. However, what you've said so far certainly doesn't prove your point.


    Cheers, John

    Ps..I've attached a nice little graph for you to think of..
    Dark blue is the dissipation envelope of the lows.
    Magenta is the dissipation envelope of the highs.
    Yellow is the summation of the two, this is biwire dissipation.
    Light blue is the dissipation envelope of both signals when they are in one wire.
    Brown is the dissipation discrepancy between mono and biwire.
    Notice it is not zero??
    Notice it goes negative??
    It is a class of signals which cannot be viewed by an FFT, as it is a zero power signal.
    Buuuut, it's there for all the world to see..

    Questions? Or, are you still gonna call me a slow learner..
    OK, I'm not saying that there is not a measureable difference. I'm aware that if you have 14/2 and go to 10/2 or something else that you can have longer runs without loss. I've also read that you should have each cable the same length. I tried this and I heard zilch, nada, no difference at all. Now, my hearing isn't near as good as it was 20 years ago, but I, like you, just don't do the bi-wire thing. I just cannot justify the added expense when I can't hear a difference.

    I'm always willing to learn, but come on with the wire thing. I think that if anything makes an audible difference it is the speaker drivers themselves. Different speakers have different sonic signatures and I can hear that. This makes logical sense to me since drivers are made from different materials, etc. But wire is wire. It's not like when I go to the DIY shows that someone breaks out the $300 cables to make sure that we are hearing the signal as it should be. Nope, it's usually some standard 14/2 copper wire from a supply store or maybe if they splurge some monster cable.

    Also, the shorter the distance the higher gauge you can go. Look at all those little bitty wires on passives. They might be 20ga tin? But since the connections are normally point to point it make no difference that they are tin instead of copper. They conduct just fine. As you can tell, I have strong feelings toward wire. I think of it as some company trying to dupe consumers into buying something that really doesn't make a difference. And look at copper prices these days. Holy cow, who wants more wire at the skyrocketing prices. I get pissed every time I have to buy an inductor and see how much they cost.

    Anyways, if I sounded abrupt my apology. My post was to help out the original poster trying to figure out what bi-wiring is. A lot of people get it mixed up so I was trying to clear the air. Then again, it was 4:00pm here with 30 minutes of work left and I didn't feel like doing any more work so fired off that comment. You take care,

    Paul

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    wow...

    hope that pic was removed before anyone else was blinded by it. Viewing was not by choice, and it was nasty.

  18. #43
    Crackhead Extraordinaire Dusty Chalk's Avatar
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    I'm going to go home and look at pictures of Giorgia Palmas and Reon Kadena until I stop feeling like sticking hot pokers in my eyes.
    Eschew fascism.
    Truth Will Out.
    Quote Originally Posted by stevef22
    you guys are crackheads.
    I remain,
    Peter aka Dusty Chalk

  19. #44
    Forum Regular hermanv's Avatar
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    Quote Originally Posted by jneutron
    Ah, tis a shame..

    It would have been nice to calculate the effective dielectric constant and characteristic impedance from your geometry.

    LC = 1034 EDC, L in nH per foot, C in pf per foot...

    Z = sqr(L/C)

    Cheers, John
    Hi John;
    We wrote it down somewhere, maybe I can find it. Although I readily admit that there isn't anywhere near full understanding of why wires sound different, I'm pretty sure that the basic RLC parameters of a wire will not fully explain the audible results. I've done much of the math and the effects of traditional wire constants are tiny indeed. I doubt that transmisson line impedance is the issue, trying for a 4 Ohm (or so) line impedance implies some physical wire results that aren't very practical, plus the wires are driven by a source impedance that usually well under 1/10 of an Ohm.

    Many theories have been put forward as to why for example metal purity matters, most of those theories revolve around grain boundaries because the long grain cables seem to sound better. I also know that many have tried to very carefully measure the predicted effects of a grain boundary (bad diodes, localized thermionic effects, etc) and no one has been able to support these theories (at least in public) to date. I only know that they sound different enough to me to warrant the extra not inconsiderable expense.

    Since we last spoke at length about wires I have reasearched a lot on the net and built many cables. I now know that for interconnect cables at least, the single most important attribute is dielectric absorbtion. Using material with very low dielectric constants (such as foamed Teflon) will result in a good sounding cable, air is even better but very difficult to implement for a home builder making one cable at a time. Low capacitance cables have intrinsically low dieletric absorbtion, but paradoxically a relatively high capacitance of and by itself does not seem to be an impediment to good sound as long as it isn't also accompanied by a high dieletric absorbtion..
    Herman;

    My stuff:
    Olive Musica/transport and server
    Mark Levinson No.360S D to A
    Passive pre (homemade; Shallco, Vishay, Cardas wire/connectors)
    Cardas Golden Presence IC
    Pass Labs X250
    Martin Logan ReQuests.

  20. #45
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    Quote Originally Posted by poneal
    OK, I'm not saying that there is not a measureable difference. I'm aware that if you have 14/2 and go to 10/2 or something else that you can have longer runs without loss. I've also read that you should have each cable the same length. I tried this and I heard zilch, nada, no difference at all. Now, my hearing isn't near as good as it was 20 years ago, but I, like you, just don't do the bi-wire thing. I just cannot justify the added expense when I can't hear a difference.
    If you re-examine my statement and the graph, one glaring thing was said. The error component, the "2ab" graph, is the difference between biwiring and monowiring when the load is a branch circuit composed of frequency directing elements (a crossover). Two very important concepts were stated...1, the integral of this 2ab error component is ZERO, meaning it has an integrated energy of zero. This precludes the possibility of viewing it using standard FFT algorithms. and, 2. Half of the error is NEGATIVE energy...as a standalone concept, this defies the first law of thermodynamics half the time..If you examine the 2ab component and the "a squared plus b squared" yellow plot, you will notice that the extreme negative dissipation point coincides with the peak positive summation point, and the sum of those two at that point is zero (the light blue line). The 2ab component cannot exist without the sum of squares component, so physics is not defied..no new laws are being created.

    But, nonetheless, there is a difference between biwiring and mono, for a two or three branch frequency dependent load. And from my simple previous back of the envelope analysis, a 120 milliohm speaker cable/connector set introduces a 1.5% error component to the node at the speaker. Nobody in their right mind would claim 1.5% is inaudible. The issue to date has been one of measuring.

    Quote Originally Posted by poneal
    I'm always willing to learn.
    I hope that is the case.
    Quote Originally Posted by poneal
    but come on with the wire thing.
    What wire thing? I have presented a simple analysis using a simple equation, shown how the error component enters audibility, explains how such an error signal defies measurement using rather sophisticated measurement tools (FFT), and simply stated that your rebuttal to the concept of biwiring did not have any "meat" to it, therefore failed to support your assertion that it is of no consequence.

    And, I only provided the analysis of the R component of the wires, leaving L and C (or more precisely, Z) of the cable alone. That is a more difficult analysis as the energy within the system is not lost, but eventually arrives at the load lagged (disregarding frequency dependent reactive of course(no need to complicate things.).

    Quote Originally Posted by poneal
    I think that if anything makes an audible difference it is the speaker drivers themselves. Different speakers have different sonic signatures and I can hear that. This makes logical sense to me since drivers are made from different materials, etc..
    I concur, but that is off topic here.
    Quote Originally Posted by poneal
    But wire is wire...
    Wire is wire, of course. And for the most part, it can be considered as lossless without consideration of it's effect on the system. However, as you can see from my simple derivation of dissipation losses, the lumped parameters of the wire cannot be discounted for low impedance circuitry such as speakers.

    Quote Originally Posted by poneal
    Also, the shorter the distance the higher gauge you can go....
    For non cryogenic runs, I use bundled 500 mcm's, 500 amps per wire..over 5 kiloamps the trays cannot support the weight, so solid copper busswork is required..

    For my big speakers, I use 12/3 extension cord with neutriks. For my HT, I use the 24awg out of the box and the free IC's, they meet my requirements. If I were concerned about this biwire thing, I'd do so...but I am not, so don't. This does not mean I think it silly, just that I do not require it.

    Quote Originally Posted by poneal
    As you can tell, I have strong feelings toward wire.
    That was noticeable. However, one should temper ones feelings in discussions within forums, as sometimes the person at the other end of the 'net may indeed have a valid point.

    Quote Originally Posted by poneal
    I think of it as some company trying to dupe consumers into buying something that really doesn't make a difference. And look at copper prices these days. Holy cow, who wants more wire at the skyrocketing prices. I get pissed every time I have to buy an inductor and see how much they cost.
    I know your pain, try pricing a 10 millihenry inductor that can handle 10 kiloamps.. And yes, I do not like the snake oil explanations either. Last night a salesguy tried to sell me an HDMI cable that had "nitrogen dielectric". Course, he has no clue what that is..

    Quote Originally Posted by poneal
    Anyways, if I sounded abrupt my apology. My post was to help out the original poster trying to figure out what bi-wiring is. A lot of people get it mixed up so I was trying to clear the air.
    Accepted. nuff said.

    Helping the poster is good, clearing up misconceptions is good (there are so many). But, as I point out, your own misconceptions with regard to biwiring did not support your argument, it would have been a more reasonable tact to ask why I stated such.

    Cheers, John

  21. #46
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    Quote Originally Posted by hermanv
    I'm pretty sure that the basic RLC parameters of a wire will not fully explain the audible results...
    That would be incorrect. However, it must be noted that RLC can be frequency dependent, and feeding a branch circuit complicates the concepts (as my trivial resistance calculations show). An industrywide lack of understanding of these interactions within low impedance loops is to blame. Given the complexity, it is expected that correlation of audibility with RLC will be lacking. That will change eventually.

    Quote Originally Posted by hermanv
    I doubt that transmisson line impedance is the issue, trying for a 4 Ohm (or so) line impedance implies some physical wire results that aren't very practical, plus the wires are driven by a source impedance that usually well under 1/10 of an Ohm....
    Transmission line theory is typically though of as an rf thing with wavelengths less than the line length. That is a simplified subset of actual transmission line theory, and is a simplification for convienience.

    Any wire pair will have a lumped L and C, and therefore a characteristic Z. The energy storage within any wire pair which drives a load (at frequencies far below line wavelengths) is minimized when the load impedance matches the line impedance. I attach a graph demonstrating this storage...the lumped capacitive, the lumped inductive, and the summation of stored energy. What is of concern is the fact that the stored energy of a typical zip approaches 5% of the energy delivered per lobe for a 10Khz signal (again, a simple back of the envelope calc done years ago).

    While I do not worry about reflections per se, what is taught as lumped element storage within the wire is indeed the result of infinite (in the limit) reflections, the lumped approximation is useable whereas reflection math is far too cumbersome.


    Quote Originally Posted by hermanv
    Many theories have been put forward as to why for example metal purity matters, most of those theories revolve around grain boundaries because the long grain cables seem to sound better. I also know that many have tried to very carefully measure the predicted effects of a grain boundary (bad diodes, localized thermionic effects, etc) and no one has been able to support these theories (at least in public) to date. I only know that they sound different enough to me to warrant the extra not inconsiderable expense.....
    Yes, the theories are rather "interesting", shall we say. It is surprising how many clearly made up garbage explanations aquire legs..

    Cheers, John
    Attached Thumbnails Attached Thumbnails Bi-wiring The question that can't be answered?-wire-energy-storage.jpg  

  22. #47
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    Quote Originally Posted by jneutron
    That would be incorrect. However, it must be noted that RLC can be frequency dependent, and feeding a branch circuit complicates the concepts (as my trivial resistance calculations show). An industrywide lack of understanding of these interactions within low impedance loops is to blame. Given the complexity, it is expected that correlation of audibility with RLC will be lacking. That will change eventually.
    My biggest problem with the RLC explanation is that bad sounding cables seem to have an additive component. This component, which sounds to me like a band limited hash, seems to be prominent at that same frquency range (within 1 to 4 KHz) that digital recordings seem to have the most problems. While energy storage as in dielectric absorbtion or in the energy stored in the reactive components can generate additive effects I wonder about the spectrum. I haven't done the energy storage math but your claim of up to 5% doesn't mention the discharge time. With 4 Ohms at one end and a very low (but rising with frequency) Z at the other end of a speaker cable how long does the energy take to discharge to let's arbitrarily say 0.1% or 0.01%?

    My second problem with the RLC explanation is that the better sounding cables do usually have lower capacitance and or inductance but that the difference between "good" and "bad" cables isn't huge, at least not compared to the change in transparancy or low level detail retrieval that I hear.

    Cables made with alloys that are magnetic (steel) do sound a little like amplifier crossover distortion. If we allow for the need of a finite AC current to flip the steel domains in the cable then this argument makes a certain amount of sense, I don't know if anyone has ever measured this. This effect would also be additive in the sense of spreading a signals spectrum or crossmodulating between two signals. The cable industry concern about metals purity could be missplaced, it might only be magnetic impurities that matter.

    Quote Originally Posted by jneutron
    ..edit..Any wire pair will have a lumped L and C, and therefore a characteristic Z. The energy storage within any wire pair which drives a load (at frequencies far below line wavelengths) is minimized when the load impedance matches the line impedance. I attach a graph demonstrating this storage...the lumped capacitive, the lumped inductive, and the summation of stored energy. What is of concern is the fact that the stored energy of a typical zip approaches 5% of the energy delivered per lobe for a 10Khz signal (again, a simple back of the envelope calc done years ago).

    While I do not worry about reflections per se, what is taught as lumped element storage within the wire is indeed the result of infinite (in the limit) reflections, the lumped approximation is useable whereas reflection math is far too cumbersome. ..edit..
    Cheers, John
    If you assume a short at one end and know the cable resistance, it's fairly easy to calculate the number of round trips in say a 2 meter long cable before the reflections damp to a small percentage. I say fairly easy, but admit to being too lazy this morning to look up the equations and do the work.

    Let me close by saying I personaly suspect a number of causes of the cable sound phenomina, the reason we can't seem to find it could easily be because there are a number of very small mechanisms at work and any one explanation won't provide a sufficient enough answer as to what is going on. There are a lot of paradoxes, why don't the wires inside a component contribute as much as those wires outside? Worse, most equipment runs the signals through PCB copper with little effort made for purity or concern about RLC constants. This does lend credence to the wire is wire crowd, the rub is that I and apparently many others can hear differences between cables and it's not particularly hard to hear those differences..
    Herman;

    My stuff:
    Olive Musica/transport and server
    Mark Levinson No.360S D to A
    Passive pre (homemade; Shallco, Vishay, Cardas wire/connectors)
    Cardas Golden Presence IC
    Pass Labs X250
    Martin Logan ReQuests.

  23. #48
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    Quote Originally Posted by hermanv
    My biggest problem with the RLC explanation is that bad sounding cables seem to have an additive component. This component, which sounds to me like a band limited hash, seems to be prominent at that same frquency range (within 1 to 4 KHz) that digital recordings seem to have the most problems. While energy storage as in dielectric absorbtion or in the energy stored in the reactive components can generate additive effects I wonder about the spectrum...
    Honestly, your biggest problem with the RLC explanation is you have not been provided a correlational link between it and what you hear. That is not your fault, but that of the industry. The end users have to rely on what is told them, and what is told them comes from the sellers for the most part. This is why there is so much in the way of "interesting" explanations out there.


    Quote Originally Posted by hermanv
    I haven't done the energy storage math but your claim of up to 5% doesn't mention the discharge time. With 4 Ohms at one end and a very low (but rising with frequency) Z at the other end of a speaker cable how long does the energy take to discharge to let's arbitrarily say 0.1% or 0.01%?...
    Discharge time is a dc style concept, which is not what I speak of. A simple inductance, for example, will simply lag the signal due to charging and discharging to the magnetic field..a simple R-L circuit, easily understood and modelled across a wide range of frequencies. What is not so simple is the difference between the energy stored with only one load present as a biwire does, and a two current energy storage that a monowire presents when feeding a two way speaker. (in the previous example, the non linear aspect was the energy loss within the wire, for inductance, it is I2L ...when the signals are combined, the magnetically stored energy is twice that of the biwire case). Twice the energy because it is only one wire?? The relevant question is..how does that energy transport to the load? It will eventually be there, the question is..when, what spectra?

    Quote Originally Posted by hermanv
    My second problem with the RLC explanation is that the better sounding cables do usually have lower capacitance and or inductance but that the difference between "good" and "bad" cables isn't huge, at least not compared to the change in transparancy or low level detail retrieval that I hear.
    As I've stated in the past, best cable is lowest practical R, cable Z equal to load, and product LC as low as possible. (note, it cannot go below LC = 1034, L in nH per foot, C in pf per foot, as that would violate the speed of light..can't go doin that, now can we?)

    Quote Originally Posted by hermanv
    Cables made with alloys that are magnetic (steel) do sound a little like amplifier crossover distortion. If we allow for the need of a finite AC current to flip the steel domains in the cable then this argument makes a certain amount of sense, I don't know if anyone has ever measured this. This effect would also be additive in the sense of spreading a signals spectrum or crossmodulating between two signals. The cable industry concern about metals purity could be missplaced, it might only be magnetic impurities that matter.
    The internal inductance of the wire is proportional to the metal's permeability, 15 nH per foot times the mu..typical magnetic steel at mu of 100 gives 1.5 uH per foot, which is certainly significant, and swamps the geometric external inductance.

    Quote Originally Posted by hermanv
    If you assume a short at one end and know the cable resistance, it's fairly easy to calculate the number of round trips in say a 2 meter long cable before the reflections damp to a small percentage. I say fairly easy, but admit to being too lazy this morning to look up the equations and do the work.
    Me too. That's why I use lumped element, there is no need to make it difficult. Using a reflective model is useful only as an academic exercise to arrive at the lumped numbers.

    Quote Originally Posted by hermanv
    Let me close by saying I personaly suspect a number of causes of the cable sound phenomina, the reason we can't seem to find it could easily be because there are a number of very small mechanisms at work and any one explanation won't provide a sufficient enough answer as to what is going on. There are a lot of paradoxes, why don't the wires inside a component contribute as much as those wires outside? Worse, most equipment runs the signals through PCB copper with little effort made for purity or concern about RLC constants. This does lend credence to the wire is wire crowd, the rub is that I and apparently many others can hear differences between cables and it's not particularly hard to hear those differences..
    The apparent paradox is fed by the tendency to treat cables as magic. It is certainly not magic. Two ugly factors are responsible for this condition..the tendency to call wires wires without regard to the underlying physics behind low impedance circuitry, and the tendency to make up ridiculous explanations using physics words pulled from a scientific thesaurus. Both are incorrect, both tend to fuel the flames within attempts to discuss the topic.

    As you can see, I take both sides to task as needed, to keep the topic focussed.

    Cheers, John

    edit.."inpedance"...sheesh
    Last edited by jneutron; 11-16-2006 at 11:20 AM.

  24. #49
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    Quote Originally Posted by jneutron
    As I've stated in the past, best cable is lowest practical R, cable Z equal to load, and product LC as low as possible. (note, it cannot go below LC = 1034, L in nH per foot, C in pf per foot, as that would violate the speed of light..can't go doin that, now can we?)
    While you've mentioned the magic 1034 constant before, I don't recall this specific refinement of "product LC as low as possible". Interesting. Here are a couple of points of reference familiar to me:

    14 gauge zip (I use in vintage system - others tout as sonically "perfect" for 8' runs) LC product=5000 .0055 ohms/ft

    JPS Labs Superconductor I use in main system LC product=1200 .0020 ohms/ft

    Nordost Valhalla (preferred by reviewer friend) LC product=1152 .0026 ohms/ft

    So far, so good!

    rw

  25. #50
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    Quote Originally Posted by E-Stat
    While you've mentioned the magic 1034 constant before, I don't recall this specific refinement of "product LC as low as possible". Interesting. Here are a couple of points of reference familiar to me:

    14 gauge zip (I use in vintage system - others tout as sonically "perfect" for 8' runs) LC product=5000 .0055 ohms/ft

    JPS Labs Superconductor I use in main system LC product=1200 .0020 ohms/ft

    Nordost Valhalla (preferred by reviewer friend) LC product=1152 .0026 ohms/ft

    So far, so good!

    rw
    Interesting. I guess you are affirming correlation.

    The actual equation is LC=1034DC. DC is the dielectric constant, epsilonr.

    This equation is derived from the coaxial equations. For coax, it is exact. For all others, it is a minimum limit.

    For others, the term DC must be replaced with epsilonrmur. Since nobody really uses magnetic material, mu is irrelevant, so the product must be replaced by a term I call "Effective dielectric coefficient", (EDC), and is used for the case of a non coaxial structure. It is related to the spillage outside the cable of magnetic and electric field.

    Whenever Gene D at AH posts any cable tests, I plug his data into LC/1034 to get the effective dielectric coeff, it pleases me to sometimes catches severe errors in the data this way, as, if that number is less than 1, there is an error. Attached is a graph of that, from one of his wire shootouts (from what I recall). While I present the data, I've no idea what each of the wires actually is nor their cost, nor their popularity..(sorry the graphs are not hi rez, saving jpegs below 100k is not very pretty.)

    The energy stored in the cable is related to EDC, and the prop velocity is also related to it via equations. So while it is possible to attribute a difference to the prop velocity, that is incorrect. The prop velocity is related to the simple LC numbers, as is the storage..

    My goal has been to correlate these parameters to "possible" audibility, you give some interesting points of data..thanks.

    Cheers, John
    Attached Thumbnails Attached Thumbnails Bi-wiring The question that can't be answered?-dielectric-coeffs.jpg  
    Last edited by jneutron; 11-16-2006 at 11:26 AM.

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