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Analysis of Paper on Measurements of RCA Cables by Kunchur (Video)

voodooless

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More easy would be talking:

I go now left, now right, now iam on my knees in the corner, ;)
Isn't it the point of not knowing where the person is? I guess you could be lying... ;)
 

Cars-N-Cans

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I can assure you,works as a charm,tested it in more than 5 systems.Along with REW let's you correct a lot of things but in the process you have to decide what matters,that's the compromises audio has as far as I have understand.
But the above is literally what you hear,your everyday,so has it's value.
I’ll have to try it out. If they only used the portion of the HRTFs needed to supplement what the speakers provide I could see such things being quite effective.
 

Sokel

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I’ll have to try it out. If they only used the portion of the HRTFs needed to supplement what the speakers provide I could see such things being quite effective.
It even works with my desk's fostex's,I play around with them changing the dimensions,is fun!
 

PeteL

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It's not complicated at all. You pose that these papers are relevant even if they may be wrong and provide valuable knowledge. I ask: what is that knowledge? And then, no decent answer comes. What Is complicated about that?

Nitpicking? Then how can you justify the conclusion? Do you agree with it? Do you agree that his so-called experiment proves you can determine height in sound via a stereo system? From the abstract:

Again: "sufficient fidelity". What is that? How is it linked with 3D spatialization? How can you prove it was the system that made the effect work? Why and how were other factors disregarded?

Nobody said otherwise. But if you demonstrate, it should be done with care and rigor, not by strawmen.
If you say so, OK.
 

voodooless

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I answered all your questions, you just don't like my answers, we disagree that's all.
If those are your idea of answers there is nothing more I can do…
 
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danadam

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Insanity Is Doing the Same Thing Over and Over Again and Expecting Different Results
— Albert Einstein

Well, now you know what I am…
Quantum Mechanics physicist/researcher? ;)
 

Cars-N-Cans

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I can't be convinced to pay 10x more for cables that in theory "may" carry information that I know I cannot hear. It's also possible that well engineered el cheapo cables can hit that max just as well (I'm sure Topping is on it)
At audio frequencies on the signaling side of things, it’s noise that’s the principal concern. Audio doesn’t look any different than DC to wires other than the fact that it wriggles up and down (maybe skin effect, but the inner conductor diameter is too small to really impact things), and the load resistance of a DAC or amp input is usually high enough to be negligible in terms of conductor resistance. But that same high source and load resistance/impedance means it’s vulnerable to AC hum and RF pickup. Any sort of RF signal that is modulated at an audible rate can potentially be heard once amplified, and linear circuits are real good at acting as AM receivers. It’s the main reason I replaced all my cables as I got tired of hum and listening to the transmitter in my cellphone. But In my case Amazon basics cables (which are probably a copy of someone else’s) had good enough shielding to eliminate that. Granted a hand-held transceiver can still cause issues, but exposing equipment of any sort to substantial RF will have an impact. But pretty much any competent cable manufacturer will be able to make interconnects that will have “SOTA” performance.
 

PeteL

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If those are your idea of answers there is nothing more I can do…
It has been covered in this discussion Voodooles, but I'll answer. Why do I feel like you won't be satisfied? Is it so hard saying that you have a different point of view than mine?

It's not complicated at all. You pose that these papers are relevant even if they may be wrong and provide valuable knowledge. I ask: what is that knowledge? And then, no decent answer comes. What Is complicated about that?

The knowledge I get from this paper, is that perception of heigh and 3d stereo image is real, not imagined and that it can be portrayed and assessed in blind listening.
Nitpicking? Then how can you justify the conclusion?
The conclusion can be justified because, in my view it has been assessed by a test that is sufficiently controlled, in my opinion. This blind testing "to the best of my knowledge" and I don't know everything, was properly conducted.

Do you agree with it?

That a correctly set up two‐channel stereo system can in fact portray not only depth and lateral width (azimuth), but also elevation for appropriately recorded material?
Yes. I agree with this conclusion unless someone could explain to me that this test is unconclusive, then I may revise my position. You did not explain why this test is unconclusive.
Do you agree that his so-called experiment proves you can determine height in sound via a stereo system?
Yes.

From the abstract:

Again: "sufficient fidelity". What is that?
I don't know, but how about he don't know? Why would he have to know? He describe the system used for testing, with the components used and the fidelity metrics associated. What that says is, I can only tell you it's conclusive on a system of enough fidelity, I can't tell you this test can be conclusive on just any system, that's correct. You appear to really want this paper to be describing what system is necessary. He is telling you that on this specific system, it's conclusive.

How is it linked with 3D spatialization?
3D: Width(1), depth(2), height(3)

How can you prove it was the system that made the effect work?
Can you? Does he conclude to that? If he did indirectly this is really a side note that you put a lot of weight to, I may have read fast and maybe some false claimed slipped trough. As I mentioned, imperfect studies is better than no studies.

Why and how were other factors disregarded?

I don't know. are the factors you are referring to would have canceled the validity of this test? reinforced them? May I know what factors you have in mind? that question is pertinent, I don't unfortunately have the answer.
Nobody said otherwise. But if you demonstrate, it should be done with care and rigor, not by strawmen.
I agree.
 
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Blumlein 88

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It has been covered in this discussion Voodooles, but I'll answer. Why do I feel like you won't be satisfied? Is it so hard saying that you have a different point of view than mine?



The knowledge I get from this paper, is that perception of heigh and 3d stereo image is real, not imagined and that it can be portrayed and assessed in blind listening.

The conclusion can be justified because, in my view it has been assessed by a test that is sufficiently controlled, in my opinion. This blind testing "to the best of my knowledge" and I don't know everything, was properly conducted.



That a correctly set up two‐channel stereo system can in fact portray not only depth and lateral width (azimuth), but also elevation for appropriately recorded material?
Yes. I agree with this conclusion granted that someone could explain to me that this test is unconclusive, then I may revise my position. You did not explain why this test is unconclusive.

Yes.


I don't know, but how about he don't know? Why would he have to know? He describe the system used for testing, with the components used and the fidelity metrics associated. What that says is, I can only tell you it's conclusive on a system of enough fidelity, I can't tell you this test can be conclusive on just any system, that's correct. You appear to really want this paper to be describing what system is necessary. He is telling you that on this specific system, it's conclusive.


3D: Width(1), depth(2), height(3) You really ask?


Can you? Does he conclude to that? If he did indirectly this is really a side note that you put a lot of weight to, I may have read fast and maybe some false claimed slipped trough. As I mentioned, imperfect studies is better than no studies.



I don't know. are the factors you are referring to would have canceled the validity of this test? reinforced them? May I know what factors you have in mind? that question is pertinent, I don't unfortunately have the answer.

I agree.
I had read this paper on height perception some while ago. Just reread it again quickly.

I think one obvious problem is people who hear something might picture in their mind someone holding a banjo just above the belt line playing it. While a trumpet player is standing with the trumpet to his mouth and often elevates his instrument upward. As that was the only stimulus it becomes highly suspect right there.

I think much better test sounds could have been used. Like having someone play a banjo at different heights. Or two or three banjos concurrently all at different heights. The idea this paper conclusively shows height is conveyable via 2 channel stereo with 2 microphone recordings is claiming far, far too much.

Now simple stereo can show height and even makes sounds come from the sides and rear. Q-sound I mentioned earlier does this. And you don't need an extreme system. Most of the effect is there even with a junky pair of computer speakers. Philips in early DVD players had a process you could turn on for creating something like surround from two speakers for videos. It also worked fairly well at least sometimes. Both of those do some processing to trick your hearing.

As you might have guessed from my username, I have done some recording (not a lot and not a pro), and one of my preferred methods is a crossed pair of figure 8 microphones or the Blumlein configuration. The paper says the recording used was two unprocessed microphones in the Blumlein configuration.

Can it show height in normal recordings? If so my conjecture would be because with crossed pairs there is a different height between the microphones. One is higher and one is lower. At some frequencies this can cause a vertical comb filtering effect which might trick the ear by being similar to how we hear height. We hear height when the delayed reflections from our outer ear and the ear canal cause comb filtering at the entrance to the ear canal. It mostly functions between 6 khz and 11 khz. Higher frequency being heard as more height. As such I'd think any height in simple stereo recordings is likely accidental or incidental. By that I don't think it will reliably place where an instrument was. It might incidentally cause some sensation of height to be heard.
 

DonR

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It would be easy to eliminate or confirm some of the biases. Record an instrument not normally associated with height using the "height" methods outlined. Vice-versa record an instrument normally associated with height and place it down low. Use various instruments that have different frequency ranges.
 

Blumlein 88

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Try this video. The video will prejudice you of course. It is recording of fireworks with a few different microphone patterns using some high quality microphones. See if you hear height in some and not others. Now this isn't a blind test, but it lets anyone reading this hear some minimalist recordings of something definitely with height. A limiter was used in these recordings. Some are in mono. Do you hear height in mono?
 

PeteL

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I had read this paper on height perception some while ago. Just reread it again quickly.

I think one obvious problem is people who hear something might picture in their mind someone holding a banjo just above the belt line playing it. While a trumpet player is standing with the trumpet to his mouth and often elevates his instrument upward. As that was the only stimulus it becomes highly suspect right there.

I think much better test sounds could have been used. Like having someone play a banjo at different heights. Or two or three banjos concurrently all at different heights. The idea this paper conclusively shows height is conveyable via 2 channel stereo with 2 microphone recordings is claiming far, far too much.

Now simple stereo can show height and even makes sounds come from the sides and rear. Q-sound I mentioned earlier does this. And you don't need an extreme system. Most of the effect is there even with a junky pair of computer speakers. Philips in early DVD players had a process you could turn on for creating something like surround from two speakers for videos. It also worked fairly well at least sometimes. Both of those do some processing to trick your hearing.

As you might have guessed from my username, I have done some recording (not a lot and not a pro), and one of my preferred methods is a crossed pair of figure 8 microphones or the Blumlein configuration. The paper says the recording used was two unprocessed microphones in the Blumlein configuration.

Can it show height in normal recordings? If so my conjecture would be because with crossed pairs there is a different height between the microphones. One is higher and one is lower. At some frequencies this can cause a vertical comb filtering effect which might trick the ear by being similar to how we hear height. We hear height when the delayed reflections from our outer ear and the ear canal cause comb filtering at the entrance to the ear canal. It mostly functions between 6 khz and 11 khz. Higher frequency being heard as more height. As such I'd think any height in simple stereo recordings is likely accidental or incidental. By that I don't think it will reliably place where an instrument was. It might incidentally cause some sensation of height to be heard.
Good points, Yes this natural position of the instrument could have induced a bias.

On an other hand, and yes, guilty of that, it is also a "bias". I have also had my times in the music business and have had some time in a major recording studio, don't wave, I never was one of those guys, and yes, you'll tell me rightfully that it's not scientific, correct it isn't but yes, it is a constant. Mixing engineers, I can't say all but all I have interacted with, perceive their mix as a 3D space where they put elements, upstage downstage left right far and front... No really, You'll hardly find one to say all you need is left right and reverb. I't is very quite possible that some are in this group, maybe, probably, they may confirm.

They work all day filling this 3D box with element, trying to make sure everything has is spot in this 3D box.
Now, I would say that yes it's not all only to do with actual position they have recorded, there is all kind of tricks to make some element appear higher and lower, and yes a live room will be much more telling,multiple mics distance, DSP effects, really, but yes, all see their mix are having a sense of height.

That of course is not a proof of anything, But to me that still make a case, I find this hard to believe that these professionals being paid big bucks to spend all day doing all that, if they where just a bunch of nut case living in a phantasy world trying for decade to get some more elevation in their mix, litterally listening over and over until those choir appears to be on a Riser compared to the lead signer...

I don't know, it seam unlikely that It can be all only in their head when you tried all your carreer to achieve that...

That said, It doesn't remove the possibility of a bias in the test we are discussing, and I appreciate this type of insight. I don't think it's a throw away piece, but sure yes, there is a weakness to it.
 

PeteL

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Try this video. The video will prejudice you of course. It is recording of fireworks with a few different microphone patterns using some high quality microphones. See if you hear height in some and not others. Now this isn't a blind test, but it lets anyone reading this hear some minimalist recordings of something definitely with height. A limiter was used in these recordings. Some are in mono. Do you hear height in mono?
May you say who you where referring to when you said "this will prejudice you?" And what you mean by prejudice? I have been quite active and it may be me, may be not me. I definitely hear a sense the sound going up in stereo and it feels less so in mono, but it's there yes. But I mean, I definitely think we can't really take that since not only it's a position, but since High frequency content fade with distance, and the distance is automatically associated with height in our brain with fireworks, +you have the video to stimulate that impression on top of that, I'd say you can't get more biased than that. Now interresting none the less. And at the end of the day, what is "biased" in that context... It's perceived as flying up. whether it's by room reflexions and complicated HRTF... Or simply frequency content tricking your brain, in the end, there is a perception of height that can be achieve no? artificially, acoustically and why not "psychologically" The outcome is that we hear height in a mix. No?
 
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