[Bullseye]

Here is a good find from astroid.

Quote:

Originally Posted by astroid /img/forum/go_quote.gif found this interesting , i agree with this 100% based on the tests i have done. Cables, Interconnects and Other Stuff - The Truth

Have moved it from another thread. But it is very related to this thread here.

 

[gregorio]

Quote:

Originally Posted by bixby /img/forum/go_quote.gif Why we continue to pull out ohms law and use frequency rewponse as the onlly thing that could account for differences in cables sound I will never understand. Is it because we have only a two dimensional oscilliscope as our tool?

It's not that complicated Bixby. Audio is encoded in the analogue domain by using an alternating current to represent amplitude and frequency. That's it, there is no more. When we have two such signals then phase can become an issue but again we can measure that easily enough. Until we learn to listen to music using telepathy we'll have to stick with this rather basic alternating current idea as we have for nigh on a hundred years. Now if you want to use a Geiger counter or a set of kitchen scales to measure frequency and amplitude be my guest.

BTW, science has moved on, or have you not heard of digital audio? However, all the complex science involved in digital audio has not changed our understanding of analogue sound. I would also add that it was blind faith which led to the assumption that the Earth was flat, it took science to make us realize it wasn't.

G

 

[Drosera]

Quote:

Originally Posted by Bullseye /img/forum/go_quote.gif Yeah, drosera, they have some DBT tests like that, however I do not see that being impossible.

Maybe, perhaps, I don't know... DBT testing of audio equipment has certainly rendered some very interesting results in the past as well. And with those kinds of results, you start to realize why it's done so rarely.

But still, I actually own the DV-575. If that thing sounds the same as a 12,000 euro cd player, I'm getting out of HiFi right now.

 

[b0dhi]

Quote:

Originally Posted by gregorio /img/forum/go_quote.gif It's not that complicated Bixby. Audio is encoded in the analogue domain by using an alternating current to represent amplitude and frequency. That's it, there is no more. When we have two such signals then phase can become an issue but again we can measure that easily enough. Until we learn to listen to music using telepathy we'll have to stick with this rather basic alternating current idea as we have for nigh on a hundred years. Now if you want to use a Geiger counter or a set of kitchen scales to measure frequency and amplitude be my guest. BTW, science has moved on, or have you not heard of digital audio? However, all the complex science involved in digital audio has not changed our understanding of analogue sound. I would also add that it was blind faith which led to the assumption that the Earth was flat, it took science to make us realize it wasn't. G

All the processes involved in an analog audio signal being passed through a wire are far, far more complex than you seem to believe. You are severely oversimplifying.

Further, the curvature of the Earth wasn't originally said to be round due to science but due to the ancient Greeks' belief that spheres are "perfect" shapes, and they assumed (by happenstance, correctly) the Earth to be the same perfect shape. This fact was later verified, but before the development of what is today known as the scientific method.

 

[nick_charles]

I understand in abtract physics terms about waves being out of phase, where the peaks of one wave match the troughs of a different but identical wave or if they are even a bit out of phase there will be an effect and a new wave form will be created by the interference ?.

What I am having trouble understanding is how a short length of speaker cable can introduce phase differences between left and right channels that were not there to sart with. To do this one channel must delay the arrival time of signals relative to the other.

I can see how this might be possible using radically different cable types for left and right channels or have a really really long length of cable on one channel and a really really short length on the other but other than that how it it possible - genuinely puzzled.

 

[JaZZ]

Quote:

Originally Posted by nick_charles /img/forum/go_quote.gif What I am having trouble understanding is how a short length of speaker cable can introduce phase differences between left and right channels that were not there to sart with. To do this one channel must delay the arrival time of signals relative to the other.

You don't need two channels to get two signals with a phase relation to each other. The skin effect, e.g., does such things within one and the same cable.
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[intoart]

Gauge makes a difference for long runs. Nothing else does. That is the truth about cables.

 

[dura]

And now the TRUTH about Bumblebees. They can't fly!
Aviation engineers proved it, and they used SCIENCE!!

 

[Dreadhead]

Quote:

Originally Posted by dura /img/forum/go_quote.gif And now the TRUTH about Bumblebees. They can't fly! Aviation engineers proved it, and they used SCIENCE!!

Urban myth. They proved they couldn't be using a standard flight method which they aren't.

It's sad that so many people who depend so heavily on science (EVERYONE who's on head-fi, unless you have someone to take your smoke signals and type them for you) is so happy to disregard it when it doesn't match their beliefs. Science is not about getting your answer or my answer but working towards getting the correct answer.

 

[nick_charles]

Quote:

Originally Posted by dura /img/forum/go_quote.gif And now the TRUTH about Bumblebees. They can't fly! Aviation engineers proved it, and they used SCIENCE!!

Urban myth I am afraid, no aviation engineer ever said this. This myth is based on an entomologist (Antoine Magnan) book from 1934 which used fixed aircraft wings as the model and suggested that a plane which was the same size as a bee and was moving the same speed as a bee could not fly, it is an absurd metaphor and was a joke enjoyed by the academic engineering community until picked up later by non engineers and hopelessly misunderstood.

 

[Dreadhead]

Quote:

Originally Posted by b0dhi /img/forum/go_quote.gif All the processes involved in an analog audio signal being passed through a wire are far, far more complex than you seem to believe. You are severely oversimplifying. Further, the curvature of the Earth wasn't originally said to be round due to science but due to the ancient Greeks' belief that spheres are "perfect" shapes, and they assumed (by happenstance, correctly) the Earth to be the same perfect shape. This fact was later verified, but before the development of what is today known as the scientific method.

The greeks also thought there were 4 elements...

Please tell me how much more complex it is to transmit a signal down a wire. Are we going to talk the momentum of the electrons (negligible) or the skin effect (again negligible).

 

[Dreadhead]

Quote:

Originally Posted by nick_charles /img/forum/go_quote.gif What I am having trouble understanding is how a short length of speaker cable can introduce phase differences between left and right channels that were not there to sart with. To do this one channel must delay the arrival time of signals relative to the other.

It depends on if the media is dispersive (ie the speed of the signal depends on the frequency). This is the case for water waves (my area of expertise) and for glass (this is the effect that causes prism to separate light) and I would assume for cable. Also if the copper wire has enough inductance or capacitance to act as a filter it also can induce a phase shift because the phase response of a filter depends on frequency.

That said this effect is immeasurable for any audio cable at audio frequencies.

 

[JaZZ]

Back to the thread topic:

Some years ago a friend and I made some listening tests with the GaborLinks (a review in Portuguese here).

These elements are meant to simulate the skin effect in a cable -- in different intensity and shape. At the same time it's said to be able to compensate for phase distortion and group delay caused by cables and the entire signal path, hence to recreate a coherent phase response throughout the frequency spectrum. So far the theory.

We listened to my friend's setup with homemade speakers using (no-name) dual-cone fullrange drivers with paper membranes -- nothing spectacular in terms of sound quality or resolving capability, but also not heavily coloring. None of us was placed in the sweet spot between the speakers, and we had different listening angles.

Even with these unfavorable conditions we both could hear significant differences with the different GaborLink elements in the signal path. And astonishingly we agreed to 99% in our judgements about which of them were favorable to the sound and which weren't, to which degree and in which respect. The differences indeed reminded me of cable sound.

So I'd recommend to give the skin effect/phase distortions a try when it comes to measurings. Not in the form of phase measurings, but rather in the form of complex waveforms -- such as a cymbal crash or an excerpt of it, resp. --, if possible analogue or in high-resolution digital (96 or 192 kHz sampling rate) for better signal-shape discrimination/identification due to the avoiding of transient corruption by the antialiasing filter.
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[Bullseye]

Thanks for the link jazz, however it is not Spanish, it is Portuguese

I can understand it, but not entirely...

 

[JaZZ]

Quote:

Originally Posted by Bullseye /img/forum/go_quote.gif ...it is not Spanish, it is Portuguese

Thanks (should have noticed it) -- edited.
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