Agreed. It is absurd to compare speaker cable, i.e. the ones with lowest impedance and highest signal level in an audio system, with turntable input, i.e. the highest impedance and lowest signal level.
Who did that? I.E. who compared "speaker cable, i.e. the ones with lowest impedance and highest signal level in an audio system, with turntable input, i.e. the highest impedance and lowest signal level".
I've never thought about speaker cable for a phono pickup, or interconnects for speaker cable. Of course if cables didn't affect the N+D and/or contribute N+D to a signal between source and sink, it would not matter if cables were mixed up. Hmmm - coat-hangers on my MC - must try!
Sorry to be cynical, but the above is merely a logical extension to some anti-science views expressed in this thread in response to the question 'Does making distortion measurement of cable make sense?'
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No need to talk about "anti-science". I think we agree that triboelectric effect and the quality of screening concerning turn-table cables can easily be measured and heard as well. Whether or not your EMC test setup is relevant for audio is debatable imho. I understood the focus in this thread being on speaker cables, maybe I am wrong.
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It's not my thread, but clearly the thread topic, and indeed the first 20 posts, do not reference speakers or speaker cable.
Whatever, speakers cables contribute significantly to perceived sound quality as I am sure you will agree, unless you're in the camp of those who think 100m of 26AWG bell wire is 'transparent'.
If someone actually did such installation, the audible effect would be contributed by the operator error.
Sure. But what is the magic length below which degradation of signal does not occur? Or does the degradation simply continue to reduce as the length does, down to diminishing amounts that approach but are never zero?
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Above statements do not tally and certainly don't allow anyone to repeat these measurements.
Cables generate noise above that of their pure resistance and can distort with a shorted input? Amazing.
Again back to your cheesy worn trick of trying to introduce unmeasurable TASTE , which is in the Psychological realm, into a Physics (Audio) based discussion,which is based on measurable parameters,of course.
How cheap is that?
WHICH tests?
Driving license tests?
Those are CRUDE tests, with minimal requirements,pass/no pass results.
If your eyes see exact same colours different, then none is linear/flat, and both are "flawed", even if they are "good enough" 🙄 to get you a driver´s license.
Again trying to introduce the unreliable psychological "test". 🙄
That, what´s wrong with those pills which promise to increase length and girth of my ....... even if it´s imagination 😉
Cool. Why bring it to a PUBLIC forum and be ridiculed for it?
Even if you achieve to get one or two similar minds backing you?
Enjoying, fine.
Measuring is also fine, if it helps improve results.
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Again back to Psychology?
Don´t you have some solid arguments? (why am I asking this? Obviously NOT)
Maybe there´s some reason for that 🙂
How do you feel inside your own little safe cocoon of Ignorance? 😱
Tolerant DIY Audio Forum does not take competence tests to join.
That said, average level is quite high anyway .... with a few rotten apples polluting the threads.
The price of Democracy I suppose 😀
Don´t be ridiculous.
Next time you will compare beef kept in a fridge for 1 week to 5000 year old frozen woolly Mamuts in Siberia in a discussion about home Freezer brands.
Easy, when degradation is below hearing threshold.
You are poorly trying to apply Zeno´s Logical FALLACY , originally used to try to "prove" that movement is impossible (go figure).
Of course, highly intelligent Zeno said this tongue in cheek, to prove those "microfractional" examples are wrong.
In your case "you can´t prove when objectionable 100m of very thin wire becomes acceptable" , same thing.
For your information, since I doubt you read the Classics, this was debunked some 2500 years ago.
Never too late to learn something anyway. 🙂
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That's because scientific disagreements can turn in to what amounts to political debates. The idea in those debates is to win by successfully influencing audience opinion. Any dirty trick that helps win is okay in political type debates so long as it doesn't sway the audience towards arriving at an undesired opinion.
Why are cables debated that way rather than discussed in a disinterested scientific way? Apparently it is because there is a lot of expensive 'junk' being sold in the cable marketplace. A small fraction of the stuff being sold is actually exceptionally good, but there is no way for consumers to be sure which it is. The politicization seems to be an attempt to reject cable discussions by anyone until the underlying choice/selection problem for consumers is fixed.
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@JMFahey,
So I hope you got rid of your frustrations and feel much better now.
But please next time don't refer to me as the poster of this all because it's not.
In what you call a physics audio discussion about making sense of cable distortion my clear answer in #299 was, NO, just because it can't be measured, so your trick argument doesn't hold, sorry.
But I never said there can't be sound differences.
So I'm with Einstein:
“Not everything that can be counted counts, and not everything that counts can be counted.”
This quote means that not everything that you can measure has value and not everything valuable can be measured.
Hans
So I hope you got rid of your frustrations and feel much better now.
But please next time don't refer to me as the poster of this all because it's not.
In what you call a physics audio discussion about making sense of cable distortion my clear answer in #299 was, NO, just because it can't be measured, so your trick argument doesn't hold, sorry.
But I never said there can't be sound differences.
So I'm with Einstein:
“Not everything that can be counted counts, and not everything that counts can be counted.”
This quote means that not everything that you can measure has value and not everything valuable can be measured.
Hans
Well, Einstein didn´t say that, nor any of the crap attributed to him in YT and social media in general.
But how would YOU know? 😀
But how would YOU know? 😀
I happen to have some experience in designing MC and low noise amps, see for example here
Designing a universal diff-in/diff-out Head Amp
This one has a measured flat input noise of 310pV/rtHz and 140pV/rtHz EIN after Riaa and A-weighting (88db-A at 0.5mV)
I can say that noise performance was almost up to the dB accurate with and without cable, both shorted but also with a 30R Cart connected, thereby reducing EIN to 74dB-A
All powered by battery to prevent any interaction with the measuring device.
So when such a sensitive circuit does not show any evidence of cable noise, I have my severe doubts about 20dB noise reduction.
Maybe you mean that some spectral peaks from EMI where suppressed by 20dB, but mostly these are outside the A-weighting region and have no impact on EIN-A.
Hans
Measurements like: We made FFTs at both ends is simply laughable.
I presume this hints that a difference seen between the two, measures the cable distortion.
Here, we are clearly in the IgNobel scientific world.
I presume this hints that a difference seen between the two, measures the cable distortion.
Here, we are clearly in the IgNobel scientific world.
How do you know he didn’t, did you ask him to verify 😀
I hope you were a bit more polite to him.
Hans
No, I didn't put a noise generator (AKA cartridge) on the end of the cable under test. The 1kΩ termination was to simulate a noiseless cartridge, with only the Johnson noise of the resistor.
What doesn't tally? DUT → low noise amplifier → measuring device (in this case a CRO). If the test isn't going to be documented you can use your own built in measuring device, AKA ears, to make a relative test: DUT A versus DUT B; There will be obvious audible differences between two different cables unless they are both very good or very similar in electromechanical properties.
Perhaps I wasn't clear in my writing however it should be obvious, the 0Ω termination is at the far end of the cable, not the measurement end. It would not surprise anyone that EMI is picked up by the cable - no cable has a perfect screen (why does DTV specify quad-shield cable?) Microphonic signal generation is caused by a number of physical electomechanical phenomena, including but not limited to changes in capacitance and inductance as the physical relationship between screen and conductors is altered by bending or vibration, changes in series resistance and noise generated as conductors move over each other.
Do try this at home. Take you favourite interconnect cable, terminate one end in any way that suits your taste, plug the other end into a phono preamplifier, then listen through speakers or headphones to the amount of hum and buzz you get, then twist and bang the cable and listen to its microphonic behaviour. What you are hearing over and above the preamp noise floor is N+D from the cable.
I was asked to do this investigation by a store because two of the world's top selling entry level audiophile turntables come with appallingly bad interconnects as standard fitment. What I didn't expect to find was that even high end expensive turntables are often supplied with interconnects that considerably limit the fidelity of the turntable. It seems crazy to me to spend many $1,000s on a source component that is limited in N+D by crap interconnects. YMMV
I must warn you that the all-wise Moderators of DiyAudio.com take a pretty dim view of rambling threads about speaker cables, boutique capacitors, Mills resistors , biwiring. Closure might be imminent.
Seems the more pointless a thread is, the longer it rambles on for. 😕
Anyhow, being quite well informed about cables, I thought I might clear the matter up.
Your typical speaker cable is 100 ohms. And about 5m long. A Child of Ten can calculate the lumped parameter values of such a cable.
Characteristic impedance - Wikipedia
Inductance of a Straight Wire: A Calculator
Comes out at 1000pF and 0.02mH. Terminate such a cable in 8 ohms, a near short, and the worst that can happen is less than 0.02mH inductance. And voltage amps won't blink an eyelid at a bit of inductance. Is 0.02mH a lot? Not really. Most tweeters are about 0.05mH inductance. So slight rolloff at high frequencies is expected. Typically a dB or so. Interestingly most coils and voicecoils are 5-10m long.
As ever, Engineers make things just good enough to satisfy most people. This is good cost-control. Perfection is generally unprofitable and a waste of time to pursue. My advice is to use shorter cables if it all keeps you awake at night. 😀
Seems the more pointless a thread is, the longer it rambles on for. 😕
Anyhow, being quite well informed about cables, I thought I might clear the matter up.
Your typical speaker cable is 100 ohms. And about 5m long. A Child of Ten can calculate the lumped parameter values of such a cable.
Characteristic impedance - Wikipedia
Inductance of a Straight Wire: A Calculator
Comes out at 1000pF and 0.02mH. Terminate such a cable in 8 ohms, a near short, and the worst that can happen is less than 0.02mH inductance. And voltage amps won't blink an eyelid at a bit of inductance. Is 0.02mH a lot? Not really. Most tweeters are about 0.05mH inductance. So slight rolloff at high frequencies is expected. Typically a dB or so. Interestingly most coils and voicecoils are 5-10m long.
As ever, Engineers make things just good enough to satisfy most people. This is good cost-control. Perfection is generally unprofitable and a waste of time to pursue. My advice is to use shorter cables if it all keeps you awake at night. 😀
There is nothing to preclude you from having decent interconnects. The 20dB difference I measured was between Canare GS6 cable terminated with Canare RCAPs and brand name audiophile cables out of the packet in the sub AU$500 price range. Audio band EMI (hum and buzz) was measured, not spikes in the ultrasonic or RF range.
It's a small world. I noticed a reference to a cross coupled Cohen topology in your preamp thread. Graham Cohen was a colleague of mine and fellow AES Section committee member for a time who passed away a couple of years ago, sadly in his mid-fifties. He was a brilliant RF and audio designer and we worked together to develop a power amplifier based on his ideas, for professional applications. I first met Graham when he presented the amplifier's novel approach at an AES seminar and approached him about developing the design. Oddly enough he built a house in the same street as my family although I had left home by then; even came to my sister's wedding. I am not a brilliant designer, or even a middling one, but I have a tenacity to get to the bottom of why things are the way they are.
Thx for answering.
What a special experience to have worked with Graham Cohen, he was one of the smart guys who contributed to what we have today.
At the same time this gives me the opportunity to correct the 74dB-A I mentioned in #453.
With a 30R cartridge this had to be 81dB-A instead, sorry for the mishap.
Hans
What a special experience to have worked with Graham Cohen, he was one of the smart guys who contributed to what we have today.
At the same time this gives me the opportunity to correct the 74dB-A I mentioned in #453.
With a 30R cartridge this had to be 81dB-A instead, sorry for the mishap.
Hans
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