Now they say differences between interconnect cables are audible in blind listening tests.. :P

[Vineethkumar01]

I suspect cables may be altering frequency response, phase/fixed time delay. This would be intentional.

I personally have no experience regarding this. But, technically, for a cable to alter the frequency response, it should have filtering capabilities brought about by appropriate capacitance, inductance, and resistance properties of the cable making up the filter. I personally would try to avoid such cables. For this kind of filter to be able to cause significant amount of delay (w.r.t audible delays), it needs to be of very very high order such that the group delay of the filter will delay ,significantly, a signal traveling at almost the speed of light. Personally, I think don't even want to think of such a contraption of a cable.

In general, if the time smear related ideas with cables come from papers like this:

http://boson.physics.sc.edu/~kunchur/papers/Audibility-of-time-misalignment-of-acoustic-signals---Kunchur.pdf

I wouldn't believe it for the following reasons: 1) The journal itself is sketchy that I wont even bother to read full papers in these kind of journals, 2) Just skimming through the paper, I can see many places where grand assumptions have been made conveniently without any proper citations, which is a strict reject if I were to review it.

 

[Hari Iyer]

Thanks. I am not interested in making audio life more complicated.
Enjoy your the fruits of DIY experiments.
Cheers,
Raghu

Thanks for admission that you don't want to put efforts in doing all this. Please don't give suggestions without trying them out about skin depth and conductors.

 

[raghupb]

Skin effect calculations:
Please correct me if I'm wrong.

Mogami W2549 is a popular wire for analog ICs
Material: Copper
Effective AWG: 22
Construction: 105 strands of 44AWG
Diameter of 44AWG: 0.0508 mm (50.8 um)

Skin depth at:
- 20Hz: 14578 um (if this cable were used to carry analog audio signals)
- 20KHz: 461 um (if this cable were used to carry analog audio signals)
- 1MHz: 65 um (if this cable were used to carry digital audio signals)

Calculator used:

Skin effect depth Calculator

chemandy.com

At all these frequencies skin depth is greater than diameter of individual strand.
So I will continue to be convinced skin effect does not matter when using Mogami W2549 as an analog or digital IC.
If it sounds different vis-a-vis some other multi-stranded cable, it is not due to skin effect, but something else.

Cheers,
Raghu

 

[Hari Iyer]

My answer -
All these are just numbers. Have you tried using them?

 

[Bloom@83]

In general, if the time smear related ideas with cables come from papers like this:

http://boson.physics.sc.edu/~kunchur/papers/Audibility-of-time-misalignment-of-acoustic-signals---Kunchur.pdf

I wouldn't believe it for the following reasons: 1) The journal itself is sketchy that I wont even bother to read full papers in these kind of journals, 2) Just skimming through the paper, I can see many places where grand assumptions have been made conveniently without any proper citations, which is a strict reject if I were to review it.

I was reading your posts with interest until this comment. Here you dismiss the journal link shared by @Hari Iyer , but this very thread starts with the exact same journal link on the main topic which you yourselves shared. Pasting below :

http://boson.physics.sc.edu/~kunchur/papers/Audibility-of-cable-pathways--Kunchur.pdf

Don’t you think you should have refrained from sharing link from journals which as per your own admission is ‘sketchy’ and lack ‘proper citations’ ?

 

[Vineethkumar01]

I was reading your posts with interest until this comment. Here you dismiss the journal link shared by @Hari Iyer , but this very thread starts with the exact same journal link on the main topic which you yourselves shared. Pasting below :

http://boson.physics.sc.edu/~kunchur/papers/Audibility-of-cable-pathways--Kunchur.pdf

Don’t you think you should have refrained from sharing link from journals which as per your own admission is ‘sketchy’ and lack ‘proper citations’ ?

Did you check the journals in which these papers were published? If not, Here is that data.
The paper that started this discussion, which you posted above is:

http://boson.physics.sc.edu/~kunchur/papers/Audibility-of-cable-pathways--Kunchur.pdf

This was published in "Journal of the Audio Engineering Society". This is a reasonably reputed journal. This is what got me excited in the first place.
This paper (I didn't know that FM Hari Iyer shared the link to this paper in this thread): http://boson.physics.sc.edu/~kunchu...isalignment-of-acoustic-signals---Kunchur.pdf
was published in the journal: http://www.ejta.org/.
I don't trust this journal.
Now if you ask me which other journals I trust. I can point to IEEE transactions type journals in the relevant area. Here is one journal where I have published my papers and have been reviewing papers for: https://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=7693
Here is one of my papers: https://ieeexplore.ieee.org/document/8666153
There are similar journals as above for acoustics and electronics and other related fields.

 

[Bloom@83]

Did you check the journals in which these papers were published? If not, Here is that data.
The paper that started this discussion, which you posted above is:

http://boson.physics.sc.edu/~kunchur/papers/Audibility-of-cable-pathways--Kunchur.pdf

This was published in "Journal of the Audio Engineering Society". This is a reasonably reputed journal. This is what got me excited in the first place.
This paper (I didn't know that FM Hari Iyer shared the link to this paper in this thread): http://boson.physics.sc.edu/~kunchu...isalignment-of-acoustic-signals---Kunchur.pdf
was published in the journal: http://www.ejta.org/.
I don't trust this journal.
Now if you ask me which other journals I trust. I can point to IEEE transactions type journals in the relevant area. Here is one journal where I have published my papers and have been reviewing papers for: https://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=7693
Here is one of my papers: https://ieeexplore.ieee.org/document/8666153
There are similar journals as above for acoustics and electronics and other related fields.

I don’t doubt your credentials at all.
It’s just that the two links posted are coming from the same server , and headed by the same ‘expert’ from the same university too. In fine print , yes the underlying sources are different , however I definitely don’t want to go into the academic credentials debate on this forum.
End of the day , most DIY products are huge value for money ; a 12x7 tube phonopre made by a senior DIYer in Kolkata for me for less than 10K is at par , if not better than IFI iphono costing 500$ that I own too.
That doesn’t mean everything they claim to be as huge sonic improvements made by changing one capacitor , or wire shielding has to be taken as the gospel.

 

[Vineethkumar01]

I don’t doubt your credentials at all.
It’s just that the two links posted are coming from the same server , and headed by the same ‘expert’ from the same university too. In fine print , yes the underlying sources are different , however I definitely don’t want to go into the academic credentials debate on this forum.
End of the day , most DIY products are huge value for money ; a 12x7 tube phonopre made by a senior DIYer in Kolkata for me for less than 10K is at par , if not better than IFI iphono costing 500$ that I own too.
That doesn’t mean everything they claim to be as huge sonic improvements made by changing one capacitor , or wire shielding has to be taken as the gospel.

I have given the links of the papers from the same same author given on his website for download in both the cases.
This is because the actual published papers are behind paywalls. Often, many journals permit authors to publish a preprint of the actual journal version on personal websites. Only these can be downloaded without paying money. Hence the links to the same author's website.

This thread is not regarding value for money DIY products. I have no arguments regarding DIY products being value for money. I am also not saying that audio companies are conspiring against us by offering whatever products they offer at whatever price they do. It all depends on one's perspective and personal tastes. But when we try to question established and basic scientific principles, in my opinion, we should be careful enough and better have convincing enough reasons to show that the idea we put forward is correct/believable. Even in this case of cable related discussions, I am not going to say that the author's and/or others works/impressions in this forum/other forums are completely wrong. Its just that I am not yet convinced by the whole idea behind it and by the amount of evidence put forward to support it, yet. It may or may not be convincing enough for others.

 

[keith_correa]

End of the day , most DIY products are huge value for money ; a 12x7 tube phonopre made by a senior DIYer in Kolkata for me for less than 10K is at par , if not better than IFI iphono costing 500$ that I own too.

DIY? How is this of relevance here or even in the equation?

 

[Bloom@83]

But when we try to question established and basic scientific principles, in my opinion, we should be careful enough and better have convincing enough reasons to show that the idea we put forward is correct/believable.

Fully in accord with this.

DIY? How is this of relevance here or even in the equation?

Feel free to ignore. I believe I made my point.

 

[keith_correa]

I believe I made my point.

Maybe you did but that is besides the point. I'm just confused why you felt it necessary to make a point of something that was not even in the fray here.

 

[Decadent_Spectre]

I personally have no experience regarding this. But, technically, for a cable to alter the frequency response, it should have filtering capabilities brought about by appropriate capacitance, inductance, and resistance properties of the cable making up the filter. I personally would try to avoid such cables. For this kind of filter to be able to cause significant amount of delay (w.r.t audible delays), it needs to be of very very high order such that the group delay of the filter will delay ,significantly, a signal traveling at almost the speed of light. Personally, I think don't even want to think of such a contraption of a cable.

In general, if the time smear related ideas with cables come from papers like this:

http://boson.physics.sc.edu/~kunchur/papers/Audibility-of-time-misalignment-of-acoustic-signals---Kunchur.pdf

I wouldn't believe it for the following reasons: 1) The journal itself is sketchy that I wont even bother to read full papers in these kind of journals, 2) Just skimming through the paper, I can see many places where grand assumptions have been made conveniently without any proper citations, which is a strict reject if I were to review it.

Wouldn't this just answer the premise of the thread? That cables do make a difference. They may not be "accurate" but there is a difference.

 

[Vineethkumar01]

Wouldn't this just answer the premise of the thread? That cables do make a difference. They may not be "accurate" but there is a difference.

I was creating a hypothetical cable which could cause filtering effects in the post you quoted. I dont have experience using one. I personally don't prefer using a cable with such effects if at all one such thing exists unless i am forced to use it. Others may/maynot want it.
Anyway it all doesn't matter now. I would gladly get out of this train of thought about cables at this point and move onto much more interesting things..

 

[k-pad]

I have not heard about or known about it.
edit: Recently i heard about a paper by the same author i refered in this thread having a written a paper on time smear etc in the past. But after a lot of controversy, it was taken down or something. In other forums i see that "removing" time smear related notions are also there behind the MQA format

Hi Vineeth-bhai,
Very interesting paper and very, very interesting subsequent thread.
I have many questions, but I'll move them to PM, which you can answer at leisure whenever you have the time.
Right now, I just want to understand one thing (a doubt about the bold part):

If I understood right: The concept of time smear as a real thing goes against the fundamentals of the MQA format?
Or did you mean: Part of MQA's foundation lies in the concept of removing time smear, which means MQA proponents accept time smear as legit?

Wouldn't this just answer the premise of the thread? That cables do make a difference. They may not be "accurate" but there is a difference.

From what I have read only in this thread, I am sure, of course there is going to be a difference.
But the How and Why has really eluded me so far.
Vineeth's and Raghu's points and your questions seem to be taking it in a rightish direction.
Hope to see further discussions along those lines...

 

[Vineethkumar01]

Hi Vineeth-bhai,
Very interesting paper and very, very interesting subsequent thread.
I have many questions, but I'll move them to PM, which you can answer at leisure whenever you have the time.
Right now, I just want to understand one thing (a doubt about the bold part):

If I understood right: The concept of time smear as a real thing goes against the fundamentals of the MQA format?
Or did you mean: Part of MQA's foundation lies in the concept of removing time smear, which means MQA proponents accept time smear as legit?
Regards

What i meant is one of the ideas behind MQA is that they supposedly remove occurance of "time smear" due to the compression process.
Here is a link i found which tries to go into the depths of this and other claims:
https://www.hifilink.fr/wp-content/uploads/2020/04/MQA-Technical-Analysis-Hypotheses-Paper.pdf
It is a fascinating read for someone interested in DSP and till wherever i have read through, it is technically correct to the extent of my knowledge. Morover, it points to the original papers which show the inner working behind the hierarchical type compression scheme that forms the core of MQA.
Ultimately, in the strictest sense, "time smear" can occur whenever we try to apply a filter with bandwidth less than the the bandwidth of the original signal, howsoever small the difference is. But the extent to which it is audible depends on a lot of other factors.
I will leave the explanations about this at this point as going into the depths of the research behind this, while personally interesting for me, may be of no value add to others.
For most people interested in audio, at the end of the day, it boils down to a single question "is it audible or not?"

 

[Hari Iyer]

For most people interested in audio, at the end of the day, it boils down to a single question "is it audible or not?"

IMO, it's audible if you are looking for it. It's obviously not audible if you are not looking for it. This logic applies everywhere not only in audio. You usually don't find "anything" if you are not looking for the "thing".

 

[keith_correa]

"Bilkul saaf ghar me bhi agar jhadoo lekar nikloge toh thoda bahut kachra milega hi." or something to that effect...