Scott
The glitches in the Geometry Matters videos (on You Tube) are due to 100-200 reflections "slowing" the rise-time of the square wave at the speaker end. This is with a basic $150 audio oscillator and a $100 Cambridge amplifier at 1 kHz. Please explain this experiment not using transmission line theory. Try it yourself!
The glitches in the Geometry Matters videos (on You Tube) are due to 100-200 reflections "slowing" the rise-time of the square wave at the speaker end. This is with a basic $150 audio oscillator and a $100 Cambridge amplifier at 1 kHz. Please explain this experiment not using transmission line theory. Try it yourself!
Very Serious Indeed! And some of the reasons are:
- Speaker cables are large audio components (in one dimension, at least)
- They are visible to the end user - unlike parts hidden inside a box
- They transmit the entire musical signal to the last component in the system
- They are easily swapped by even the least skilled audio hound
Why would they not become a fetish item and the target for marketing and argument? It's basic human nature. Nothing wrong with that.
I asked a simple question, how? What audio amplifier has <<15ns rise time and a return loss to support a 100 or more reflections. The Zobel kills the 0 output impedance at HF not that an audio amplifier has one.
Please, let-us be serious. if you can reproduce this phenomena (it was difficult to experiment, as i said), just afeter: compare with the same signal, plugging your loudspeaker as the load. And after, do this whith a microphone in front of them.
It is like polishing a 1µm stone, and hoping it will change a montain landscape.
Pano, i kiss you.
It is like polishing a 1µm stone, and hoping it will change a montain landscape.
Pano, i kiss you.
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Hi,
Yet at high frequencies your cable behaves as unterminated transmission within significant field strength EM fields. So transmission line theory does apply to the speaker cables you use, sure not in a direct manner, but an indirect one, but it applies...
As for Chlorophyll, it reflects certain parts of visible light, which in your perception are tagged "green", but which are not "green" in any sense of absolute reality, so Chlorophyll is green only in your perception and because you learned associate the particular pattern of reflected with the tag "green"...
Yet "green" is merely a collective delusion.
So yes, your speaker cables are subject to transmission line theory in the precise way in which chlorophyll is "green".
Ciao T
Yet at high frequencies your cable behaves as unterminated transmission within significant field strength EM fields. So transmission line theory does apply to the speaker cables you use, sure not in a direct manner, but an indirect one, but it applies...
As for Chlorophyll, it reflects certain parts of visible light, which in your perception are tagged "green", but which are not "green" in any sense of absolute reality, so Chlorophyll is green only in your perception and because you learned associate the particular pattern of reflected with the tag "green"...
Yet "green" is merely a collective delusion.
So yes, your speaker cables are subject to transmission line theory in the precise way in which chlorophyll is "green".
Ciao T
A nice video and I have tried it myself. The little glitches look to me like the inverted signal has been low pass filtered. At about 40-50Khz. Not something I worry too much about. It might even be beneficial.
Scott
I am describing the general details of an experiment I observed some time ago. I
do not know what the actual amp was ( in fact I think there were several)
but they would have been Class A/B S/S. I understand your natural scepticism so it
looks like Im going to have to repeat the experiment and publish the results here.
I understand its difficult to take my word for it without hard facts.
Esperado
The test was merely to show whether there was an transmission line behaviour
in speaker cables not whether there were any sonic effects caused.
I said I understand that you cannot hear any significant effects please
understand that I can.
I am describing the general details of an experiment I observed some time ago. I
do not know what the actual amp was ( in fact I think there were several)
but they would have been Class A/B S/S. I understand your natural scepticism so it
looks like Im going to have to repeat the experiment and publish the results here.
I understand its difficult to take my word for it without hard facts.
Esperado
The test was merely to show whether there was an transmission line behaviour
in speaker cables not whether there were any sonic effects caused.
I said I understand that you cannot hear any significant effects please
understand that I can.
We where unable to notice anything (but it was long time ago ;-)with amplifiers. Phenomena hiden in the Noise and EMI. So, we used high frequencies generators and oscillos.
It was the time i was tring to mesure all the mysteries of the electro acoustic audio systems.
At the end, this searchs were just like trying to record the big bang echo ;-)
So, i had change my mind, and began to record Rock'nroll bands.
That amplifier is not capable of exciting the system at 100MHz. Those glitches look a lot longer than a few micro-seconds in the first place and secondly reflections cause both plus and minus steps depending on mismatch.
In all fairness has anyone done the equivalent lumped R/L/C comparison?
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These equations continue to apply, but lose most of their relevance at audio frequencies in combination with the lengths of cable we are talking about here.
The point, on my side, is not to believe or not.. The point is to work on usefull thinks. Means you can reproduce and apply by design to your technology. And by decreasing order on importance on the quality of the product you want to build.Zeta4;2664912I said said:
What the meaning to works on details that have less impacts than a change of temperature or humidity in listening experience ? When so many things are hundred times a magnitude of effects.
As long speakers technology will stay as it is, i will no matter how are the cables to plug them. (Ok size matters).
And i prefer to work on IM distortions and slew rate of my amplifiers than on 15ns signals witch have no luck to produce any current in the loudspeakers (considering their self inductance) or any movement, considering their inertia and the frequencies of the phenomena.
Did i make myself clear ?
Of course, the situation would be a lot different id i had a lot of cables to sell and to make money with. I'm sure i would find a lot of convincing arguments to increase my margins.
Ok, Zeta, i believe you can hear the difference. Did-you believe if i says i can replace the amplifier you used with one (a good one) you will not notice any cables difference, in regard of the huge difference of sound with your actual amplifier ?
(i do not sell amplifiers or any audio equimement)
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Hi,
And?
You do not have any RF where you live? No TV Broadcast signals? No Radio Broadcasts? No Cell phone signals? Nothing?
What planet are you on?
Ciao T
And?
You do not have any RF where you live? No TV Broadcast signals? No Radio Broadcasts? No Cell phone signals? Nothing?
What planet are you on?
Ciao T
That the reason why i use a shield on my loudspeakers cables, and why i'm VERY happy to not listen any difference, listening to music, when my sun send a SMS to his girl friend.
As i said, let-us be serious.
I can agree on that.
But, its kind of eazy to prevent those rf frequrncies from affecting audio quality. AES48 has acounted for these kind of situations to.
Esperado
I have proved to myself that cables of the "impedance matched" kind sound better to me than others I have tried over the last 15 years or so. Its not a massive effect but
worth it to me. As an engineer I wanted to know why.
Sure there are many other elements that can have a much bigger effect but thats no reason to ignore something that I think matters. Ill say it again if it doesnt matter
to you then OK.
Scott
By the way its was 15ns delay not rise time.
I have proved to myself that cables of the "impedance matched" kind sound better to me than others I have tried over the last 15 years or so. Its not a massive effect but
worth it to me. As an engineer I wanted to know why.
Sure there are many other elements that can have a much bigger effect but thats no reason to ignore something that I think matters. Ill say it again if it doesnt matter
to you then OK.
Scott
By the way its was 15ns delay not rise time.
A clearly resolved 15ns step requires a signal much faster, and it's 30ns round trip not 15ns.
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