The "truth" about different speaker cables - Page 12

Would you care to elaborate on this?

What's different as far as capacitance and inductance is concerned whether a signal is steady state or transient?

Why would you want to make cables that match speaker impedance? Why would you want half of your amplifier's power going into driving the cables rather than driving the speakers?

k

He's not talking about resistance, but wave resistance: the product of capacitance x inductance. S/PDIF connections are designed for 75-ohm cables, RCA connections are designed for 50-ohm cables. You can design speaker cables with ~8 ohm wave resistance, you just need enough capacitance to suppress inductance at the same time. That's what the patent is about.
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Q

I'm calm, my problem is you have this as your signature, big BOLD and PRoud of it. YET, YET YET , YET (Ok now I'm pissed, actually I really wasnt pissed until you posted that above, I read the article and I Thought it was useful info but your post above REALLY REALLY REALLY PO'd me) YOU CLAIM its nothing, meaningless, useless pointless because its not your work. Its sheer stupidity, to claim somethings truly profound, something so spectacular and amazing, something worthy of "a signature" in BOLD, as a reference and to call it the "TRUTH" and then hide behind the statement... "I didn't write it". Although we ALL know you believe it and continue to propagate information that you have neither verified, (and from what I can tell now) nor understood.

As far as I'm concerned, if you won't uphold the statement, remove it from your sig and stop calling it "The Truth " because trust me, if I ever found the truth about anything, you better believe that I will uphold it to the very end and never say.. oops you can't touch me or make comments to me because it wasn't my idea, I didn't write it.

Just stupid.

/End Rant

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Ok now onto more pressing stuff from Koyaan I. Sqatsi's

The question about impedance lies with impedance matching for components, like how we use 75Ohm impedance coaxial cables.

As for Capacitance, inductors, and impedance, these are all time and frequency dependent devices, meaning that their behaviors are affected by the operating frequency of the system and are also time dependent. Look into what capacitors are used for particularly when they are used as filters to block or allow certain signals to pass through (the article actually covers a bit of this, but check on the net for other sources to get more info on it). In the simplest way to explain it, capacitors will act as filters, voltage sources, resistances(impedance in this case) etc... and when you're dealing with a cable covered and shielded by dielectric material, you will get some parasitic capacitance (once again the article covers this). These parasitic capacitance can add up to affect the audio signal. Seeing as capacitors are crucial to EVERY other component in audio, I would assume they matter with the cables as well.

I'm sorry for the brief and vague responses, but trust me when I tell you that all of this info is readily available online, and I would urge anyone and everyone help themselves and the community by being better informed rather than taking my word or in this case "not" Bullseye's word for it.

And to those reading this, understand that I am neither a member of the snake oil team or the super magic califragilisticexpialidoucous team. I care about what I hear and what I know. As far as I'm concerned both sides of the fence seem to be DB's who latch on to whatever tiny bit of info they have to say "Ha, you're wrong, I win, I'm smarter than you," when in reality all they have is a tiny piece of the puzzle. The stupid part is, because they have been accepted their pace in either team snake oil or team magic, they close themselves off from actual criticisms, additional research/articles etc.. and continue to self-service their group stroking their own egos until they eventually explode and find themselves surrounded by their own sticky gooo of shameless self promotion. My point is, open yourselves to other points of view, look into the articles you read, question their validity, the source etcc (from what I can tell the original article may not be from a scientific journal -the writing is all .. well odd and trust me I've read hundreds of articles since being a student and they all follow a specific format).

"A little bit of knowledge is a dangerous thing." I think this, and several other team snake oil threads certainly prove it.

I won't post here again until said poster admits their part in all this and accepts that shamelessly promoting a thread they don't believe in is BS. Just Sheer BS.

Goodluck to anyone in the search for the truth, you won't find it in these forums so long as these two parties continue to flag and flood threads, and stay closed minded.
/End second rant

What he's talking about is impedance. And I know what it is.

No, impedance is not the product of capacitance x inductance.

What the patent is about is a load of crap.

As I stated previously, a cable doesn't have a "characteristic impedance" at audio frequencies. And if your cable's impedance is in fact 8 ohms, and you're driving an 8 ohm loudspeaker, half of your amplifier's power is being used to drive the cable, not the loudspeaker.

In other words, it's fundamentally no different than if you took an 8 ohm resistor and wired it across your speaker terminals. Half of your amplifier's power is wasted driving the resistor.

Again, the patent is nothing more than a bunch of marketing BS.

k

Impedance (which is what alternating current experiences when "it" tries to move down a cable) is : Z=SQRT(R^2 + (XL - XC)^2). With XL=2*pi*f*L and XC=1/(2*pi*f*C) you should be able to establish it for yourself fairly easily that knowing the product of L and C will not give you any useful information at all. There is no change in inductance that you can compensate by just changing capacitance (and vice versa). You want to read up on telegraphers equation to know how transmission lines work, why and how the knowledge was gained (and when for that matter).

It is ironic that later in your post you use the quote "A little bit of knowledge is a dangerous thing" as your statement here provides a very good illustration of that quote.

You know enough to know that there is such a thing as impedance matching and that relates to using such things as 75 ohm coaxial cables. However it's obvious that you don't know enough about it to understand why it has no relevance to loudspeakers and speaker cables.

Impedance matching is only germane to systems where the electrical wavelengths are approaching the length of the line carrying the signal, which is generally the case for radio frequencies and above and for high speed digital transmission.

The reason impedance matching is critical in these instances is because when the electrical wavelengths are comparable to the length of the line, impedance mismatches can cause reflections and standing waves which can result in less efficient signal transmission and in the case of digital, garbled data.

However at audio frequencies, the whole notion of reflections and standing waves goes out the window as the line lengths are microscopically small compared to the electrical wavelengths.

A typical speaker cable will be around 6-10 feet in length. However the electrical wavelength at 20kHz is on the order of NINE MILES.

Furthermore, as I'd stated elsewhere, a cable doesn't have a characteristic impedance at audio frequencies. At audio frequencies, a cable's impedance is dominated by resistance and capacitance. Therefore a cable's impedance at audio frequencies varies in a linear fashion from thousands or even tens of thousands of of ohms at 20Hz to tens or hundreds of ohms at 20kHz.

It's not until you hit around 100kHz and above that the cable's impedance begins to have what's commonly known as a characteristic impedance which is the square root of L over C.

So for Goertz to say that their cable has a characteristic impedance of 20 ohms, it's only 20 ohms well above any frequency that your speakers will ever reproduce, let alone at any frequency where the loudspeaker's impedance is 8 ohms.

They simply don't know what they're talking about.

Furthermore, a typical dynamic loudspeaker's "nominal impedance" figure only applies to a rather narrow band of frequencies. A typical dynamic loudspeaker's impedance varies greatly across the audio spectrum. So even if you did want to mach impedances, you could only do so for a rather narrow range of frequencies.

Yes, the cable's capacitance acts as a simple low pass filter. So you don't want too much of it in a cable if you don't want to filter out high frequencies to any degree.

Though a cable's capacitance generally doesn't have much effect with regard to speakers which are low impedance devices. Instead, it's a cable's inductance that will tend to limit high frequency response.

k

I'm not sure what you're talking about. Wave resistance (in German Wellenwiderstand) is a product of capacitance and inductance (well, the mathematical symbol «x» is misleading, so I left it away this time). The higher the capacitance with respect to inductance, the lower the wave resistance. And vice versa. That's why there are cables specified as 50- and 75-ohm cables (and that's not their ohmic resistance, which may still be near zero!). So you can easily build a 20-ohm cable (with ~0 ohm ohmic resistance), as demonstrated by the link.
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So you're saying the whole audio industry got it wrong with its 50-ohm standard for analogue interconnects...
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Not taking up either side on this debate I can say that there is such thing as 100% absolute truth. A lot of people are relativistic in their viewpoint today. This effects how they judge everything in life including important matters like eternity and trivial matters like subjective hearing.

Care to tell about your view on the absolute truth with respect to eternity and subjective hearing (or anything else)? I'm just curious about 100% absolute truths.
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There is no 50 ohm standard for audio interconnects. The fact that an RCA plug has a characteristic impedance of 50 ohms and the fact that consumer audio gear uses RCA plugs have absolutely nothing to do with one another.

k

Thank you.

k