Take an FFT of the noise with ca. 5Hz bins and do the same with the signal and you will see that the music pops up above the noise bins.
Hans
Wires itself have no directionality.
Cables with arrow have their shield connected to the source side together with the signal gnd.
On the recieving side only the wire with the signal ground is connected to the plug, but the shield is not connected.
Hans
Hans,
Actually, doesn't he talk about when the load impedance is high versus low? To me that specifically means there is no RF termination.
So it appears he is talking about audio frequencies exclusively, regardless of the open loop bandwidth of the driving amplifier.
On the subject of amplifier/cable interaction, most likely it is one factor to consider although maybe not the only one. The training of an EE is often to simply things as needed to make design problems practically tractable. Thus we tend to think of power supplies as separate modules from loads such as amplifiers (and use PSRR specified at LF as a sometimes rather vague justification, even though both source and load may potentially interact dynamically at much higher frequencies), interconnect wiring as separate modules from amplifiers, etc. Of course, conceptually those sorts of basic models as separate functional blocks are approximately true, but maybe not sufficiently comprehensively modeled enough to explain all audible effects?
Mark
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100R - 120R is roughly Zo for balanced cable. OTOH, my Audeze headphones are about a 30R load. A bad mismatch for a balanced cable?
Some people claim cables are always directional. Of all the things that people claim to hear, that is one that does a lot of damage to listening reports being given any credibility at all. IOW people who claim to hear differences in cable direction are giving all listening reports a bad reputation. Let's try to stick to listening reports which people 'with ears' (as they are sometimes referred to in the business) can agree upon.
I personally don't give a bad reputation to anyone.
The only problem is, we just simply don't only listen with just our ears.
If we like it or not.
We don't see with only our eyes either, nor is the perception of any sense not in large part a function of the brain. Yet, we don't know how to measure everything we can hear, at least we don't know how do so easily.
Another human perceptual bias is to over-weight what is seen in spectral analysis without admitting to ourselves that spectral analysis has rather poor predictive power for what what something will sound like. About all we really know is that poor measurements tend to correlate with poor sound. However, a convincing stereo illusion does not necessarily follow from nice looking measurements.
Another human perceptual bias is to over-weight what is seen in spectral analysis without admitting to ourselves that spectral analysis has rather poor predictive power for what what something will sound like. About all we really know is that poor measurements tend to correlate with poor sound. However, a convincing stereo illusion does not necessarily follow from nice looking measurements.
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Well..........
But besides that, even with listening, there are ways to at least minimize the bias.
What is important to understand, is that it is NOT a judgement.
Just an awareness.
That would confirm, given the steep slopes of the input signal, that the shown images are most likely smeared with reflections.
The amp’s open loop BW has nothing to do with reflections.
Terminations having an impedance way above or far below the char. Imp. are the points were reflections occur.
When this happens to be true at both ends of the cable, you may get undamped reflections as from 1/4 wavelength or higher of the cable’s propagation time.
To my opinion the mismatch between what hear and what can be measured leads to ongoing discussions.
But with the knowledge we have, we can go as far as using experiences that have proven to be beneficial.
One such thing is to prevent reflections from happening.
Hans
Not only for balanced cable, but also for non balanced cables, LS zip cords etc, etc.
Your headphones are about 30R, but also at 1Mhz and far above ?
When true, they still (over)dampen and kill reflections.
That’s the point with speakers, they are specified f.i. as 4R or 8R, but only at audio frequencies.
At HF they have impedances that will be seen by the cable as open ends.
Hans
“Let's try to stick to listening reports which people 'with ears' (as they are sometimes referred to in the business) can agree upon.”
I was unaware audiophiles agree on anything. My bad.
I was unaware audiophiles agree on anything. My bad.
Hans,
I know about reflections. Anyone who doesn't might want to read the document at: https://download.tek.com/document/55W_14601_2.pdf
The thing is, who cares about reflections if there is nothing for the reflections to interact with? For example, if an AC generator drives a pair of wires at the other end of which is connected a vacuum cleaner, do reflections change the sound of vacuum cleaner motor? Should a 100R resistor be strapped across the motor?
Then there is also the potential problem when you tell me a 100R resistor should be put in parallel with an audio input transformer. The end of the line would then have 100R in parallel with the transformer Z at RF frequencies. That parallel network at the end of the line may or may not be anywhere near 100R.
Mark
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Sorry Mark,
Let’s agree that we completely disagree. 😊
But this is not the right place for a discussion in more detail.
Hans
Let’s agree that we completely disagree. 😊
But this is not the right place for a discussion in more detail.
Hans
Assume for a moment I’m correct that all wire and cables are directional, I.e., they sound better in one direction than the other. That would cast doubt on all reviews and tests involving not only cables and interconnects, power cords and fuses but all all electronics and even speakers. This is big. Big big. Bigger than big.
Yes, I know what you’re thinking: “how can cables or fuses be directional in an AC circuit? The signal goes both ways.”
Yes, I know what you’re thinking: “how can cables or fuses be directional in an AC circuit? The signal goes both ways.”
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By 'better' you mean different? If so, specifically what is different about it?
Can you identify the direction blind? IOW, can you memorize exactly what is different about the sound, then reliably use that memory to identify the connection direction blind?
What if you move the wire around, does anything change then? Hum? Noise?
Also, how do you propose to account for AC traveling in both directions?
You just described the difference in sound due to a .2dB or so volume level difference. How are you measuring volume level is the same each time someone else either switches the cable direction or not, without you knowing which direction they put it, of course?
Don’t be silly. not even close.
I knew it wouldn’t be long before blind testing raised it’s ugly head. Results of a blind test don’t have any significance if they’re negative. Does that surprise you?
I knew it wouldn’t be long before blind testing raised it’s ugly head. Results of a blind test don’t have any significance if they’re negative. Does that surprise you?