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Ten Biggest Lies in Audio (1 Viewer)

chrisCo

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Dec 24, 2004
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That's just not the way electricity works. Although you may want to model the electrical signal between the amp and the speaker posts as being some multi layered, complex stream, it really is not. At any given moment it is a specific single voltage at a specific single current. If there is a variance in voltage/current between speaker and amp the speaker wire is failing to perform it function correctly. The real solution is bigger/better/fixed wire between points not an additional path of the problematic conductor. All bi-wiring does is move the jumper from between speaker posts to the amp and makes you buy twice as much speaker wire.
 

Shiu

Second Unit
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Feb 18, 2003
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I just measured the currents in my four pairs (bi-wired front channels) of cables of identical length, type, and size. Using the same track on the same CD, the LF pair carries 3 times the current of the HF pair when the bass drum hits. I tried my best to explain this in terms of electrical principles. If you insist this is not how electricity works, I would have to agree to disagree.

FeisalK, before I move on, just one last attempt, the amp does not know which wire to send but at the speaker end if the crossover networks are split, then the pair of cable that goes to the LF XO can pass mostly LF signals, not full range because the XO will tend to block the HF. Similarly the HF XO will tend to block the LF on the other pair of cable so it won't carry full range neither. A link to read what others have to say about this:

http://www.whathifi.com/newsMainTemp...ewssectionID=3

If other E.Es on this forum would like to shed some light on this, be my guest, I am done.


Thank you Chris for taking the time to discuss this controversial topic.
 

FeisalK

Screenwriter
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May 1, 2003
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1,245
I guess it makes sense that the filtering would be effective (i.e you can place the x-over anywhere) along the signal chain
 

Dick Boneske

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Dec 31, 2004
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What this article said in the year 2000 is what I have believed for many years. It's too bad people will continue to spend millions of dollars on things that DO NOT make their system sound better. Why is it so hard to convince intelligent people of the truth--especially A/B testing. This is the only positive proof of performance of any component in your system and, in most cases, can be done yourself without too much effort.
 

Jacob C

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I am not a physicist but have taken my share of physics classes and I am inclined to believe that the signal is going to be different on each line eventhough they are merged at the amp. It has been a while since my electricity class (not to mention I haven't used it since) but it would seems that it doesn't really matter where the crossover is in the line. The loop going to the tweeter is going to have different electical properties than the one going to the mid-woofer due to different drivers and crossovers. From that I believe that there are going to be measurable differences in the lines as Shiu showed.

A better question is if this is making a difference in the signal after the crossover. What I would like to see is a post crossover measurement on a single wired unit vs. a bi-wired unit. If different, there will be differences in sound but it may not be significant (i.e. audible).
 

Philip Hamm

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If you think a Tube Screamer from Ibanez makes authentic sounding tube distortion, I've got a bridge to sell you. Better yet, a Fender Blues Jr. amp which you can crank to your hearts desire....
 

ChristopherDAC

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I hope you realise that this is totally meaningless. You haven't specified what kind of meter you're using, but this is an AC signal of varying spectral content, so a normal ammeter isn't going to tell you anything.

Anyway, the point is that the instantaneous sum of the electromotive forces in the two wires will be exactly equal to instantaneous value of the electromotive force in the one-wire case. We know by Fourier's Theorem that the signals in different frequency ranges DO NOT INTERFERE WITH ONE ANOTHER, so the simple act of effectively moving the passive crossover from one end of the speaker wire to the other can have no effect at all. One might as well simply run a wire of double area to one terminal.
 

Yong Chan

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A little off topic, but pertinent to the article...Went to Best Buy/Magnolia to buy a new HDMI DVD player-the Samsung 950, I was told by the Magnolia(BB's new instore boutique for "high end" electronics) salesperson that I should also buy the high end "shielded" HDMI. Thought he was full of crap then. With a digital signal, does shielding make a difference in a digital signal? The article states, "The 0's and 1's are inherently incapable of being distorted in the signal path". This was in reference to the superiority of digital audio vs analog, but doesn't it also apply here?

YC
 

Philip Hamm

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Yeah the guy was full of it. All the sheilding you need is built into basic HDMI spec. Go to www.cablesforless.com or any of a host of other internet budget cable dealers for 100% adequate cables for a tiny fraction of the price that stores charge. Cable is the most shameless heinous rip-off in the audio/video world.
 

Shiu

Second Unit
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I did my fair share of Fourier analysis but thank you for reminding me of it. Other than that, as I said I was done with this bi-wire thing.
 

AlbertD

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If you think a Tube Screamer from Ibanez make authentic sounding tube distortion, I've got a bridge to sell you. Better yer, a Fender Blues Jr. amp which you can crank to your hearts desire....

I didn't say that I thought an Ibanez tube screamer made authentic sounding tube distortion. I said what it was supposed to do, and then actually asked if this was accurate or not. I guess from your post that it isn't, but don't quote me saying things that I never said or implied.

On the other hand, what I eventually did was buy a Traynor tube amp and put my Ibanez tube screamer on the shelf.
 

ChristopherDAC

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Sorry, it's just there's always some wakko hanging around who flatly denies the validity of the Fourier transform, or Nyquist's sampling theorem, or some equally fundamental principle of signal processing, and goes on from there to tout some "tweak" to be applied in the chain to mysteriously enhance the sound. I get so exasperated with these guys! If there's anything "magical" about live sound, which defies the rules of mathematical physics, it's gone when that sound hits the mic. From that point on, it's all electricity, and THAT plays by the rules, like it or not.
 

JeremyErwin

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Validity of the Fourier transform? What the deuce are you talking about? The Fourier series is an infinite series. Any engineering application of the underlying mathematics is, at best an approximation. It may be a good approximation. It may be a bad approximation. It may be an approximation that is so good as to have an unmeasurable error. But it is still an approximation.

Now, Shiu has gone to some trouble to measure--to actually test whether these approximations hold up. There may be something wrong with his instrumentation, but if the effect is still there and repeatable, it's time to integrate this into what is known about audio.
 

SteveCallas

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Dec 23, 2003
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475
Yong - I've read countless reviews of the Panasonic S77 with HDMI besting the Samsung, just something to look into.

It's gotten to a point where I hate even stepping into an audio store. I have to hear all their bs and try to be nice about it. The latest I heard was that if I buy bookshelves and cross them over to a sub at 80hz, I'm wasting my money, all speakers should be run full range. Ok.
 

ChristopherDAC

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I'll tell you what I'm talking about, in regards to the Fourier Transform. There's always somebody who doesn't understand that dynamic range at high frequencies and transient response are THE SAME THING. That's what I'm talking about.
It's not an approximation, it's a mathematical fact, that any waveform satisfying certain criteria so broad as to be met by virtually any waveform encountered in real life except possibly the shock from a megatonne thermonuclear bomb at a range of less than ten metres, is exactly equivalent to the sum of superimposed sinusoids of a certain amplitude-frequency distribution, which is infinite in the general case but FOR EVERY CASE OF INTEREST IN AUDIO AND VIDEO can be treated as finite in extent, and very often as made up of components at discrete frequencies.
The currents Shiu measured in his two sets of wiring are exactly the same currents he would have measured if he had run one set of wiring and applied his ammeter to the leads coming off the speaker crossovers. That's not an approximation, it's an absolute fact, and we're not dealing with "audio" here, but with a time-varying electrical quantity. Audio is what goes into the mic and what comes off the driver: everything in between is electricity!
Think about it. What effect are you going to get by moving the passive crossover from one end of the wire to the other? NONE. It's not hard to prove, on paper by theoretical means or using finite element analysis on computer, the result is the same. I'm sick and tired of people who claim that "such-and-such is only an approximation" without even thinking about what's going on! Come at this logically, and ask yourself exactly what possible, concievable effect moving the point of separation in a one-to-two signal path could have. If there were any effect at all, you could expect to get half of it by splicing the one run of speaker wire out into two runs halfway along the length, but any reasonable person can see that there's nothing happening there. Guess what: if there's no effect there, there will be no effect of moving the splicing point to one or the other of the two ends. It's only that people see the "inputs" or "outputs" at the two ends, and figure that something special must be happening there, but that is DEAD WRONG.
 

Chu Gai

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There's a little schematic and some rudimentary analysis of the whole biwiring thing over at pcavtech for those who are interested. While one can hypothesize, measure, this whole thing to death, it might be more beneficial to determine, in an unbiased and controlled fashion, if there is an audible difference between biwiring and an identical length and gauge of wire that's not biwired.
 

JeremyErwin

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Biwiring is a tweaker's paradise. It allows for a certain degree of variation-- thin wire for tweeter, thick wire for woofer-- all at a fairly reasonable price, assuming that cable exoticism is kept to a minimum. If the experiment shows a difference, all very well and good. If not-- well, perhaps you've wasted $50 worth cable and an afternoon or two. Big deal.

Now, I don't have a biwireable speaker system. If I did, it might make for a fun weekend-- but I don't. And I'm not going to pretend to know that some Infinity engineer had it right.
 

Elliot_W

Agent
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Apr 3, 2003
Messages
47



I had Paradigm Studio 20s paired with a PSB 15" sealed sub, and it sounded great....used the crossover in my AVR. In essence, you're bi-amping in such a configuration. The detail and imaging was just fantastic from the 'digms...although the base was not as accurate as one would get in a quality floorstander. My experiences anyways.
 

Shiu

Second Unit
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Feb 18, 2003
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447
ChristopherDAC and JeremyErwin, I am sorry to see you guys arguing because of something I wrote. Although I said I was done with this bi-wire thing but let me comment one more time on the electrical side.

I agree for the most part with ChristopherDAC on the Fourier thing. I also agree that the total currents would have been the same if I measured them all in one single pair of cable (i.e. no bi-wire). But he misunderstood my point completely. I was trying to say, and show, that when you bi-wire a speaker that is designed for it, you end up having the high frequency flowing in one pair and the low frequency in the other. The total is the same, but each cable will carry currents of different frequency range according to the crossover design.

And yes, I do realize my measurements did not mean much in the sense that the Hoiki meter I used is presumably designed and calibrated for 50 to 60 Hz signals. Chances are it failed to capture the true RMS currents of the time varying spectral signal that Christopher referred to. In order to get accurate measurements, I would have to capture the waveform with a Hoiki recorder or scope, and then perhaps do a Fourier analysis to get all the frequency components sorted out......., it gets too complicated for me to keep going. Last time I did any Fourier analysis was at least 10 years ago so let me stop right here as I have no intention to go through my bookcases any time soon.

That said, I hope Christopher would agree that my measurements still meant something, at least in relative term. It showed, in fact, the two identical pairs of cables carry currents of different magnitude and/or "spectral contents", granted the magnitude was inaccurate as I have already agreed to.

And I want to be clear, I have never said bi-wiring will result in any sound quality improvements. I just wanted to make the point that it would result in having two pairs of cable, each carrying a different band of frequencies as determined/enforced by the two split crossover network at the speaker terminals.

Chrisco's statement, "That's just not the way electricity works" got me started.... I shouldn't have reacted to it.
 

Elliot_W

Agent
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Apr 3, 2003
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47
Ok, for those of us without the PhDs, to bi-wire or not is a case of which ever sounds better to the listener:

i. Having the speaker's full complement of internal crossovers do the work (single wiring).

-or-

ii. Having 2 speaker wires carry different frequencies and perhaps using only the crossover at the speaker terminals (bi-wiring).

In any case, nothing to do with increased current, output from the amp, etc. Of course, the question remains if there is any scientific reason why these two methods should produce different sonics.
 

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