Hi,
In an article on audio cables I wrote over a decade ago I called these "first order" effects and ascribed MOST gross subjective differences between cables of dramatically different construction and electrical parameters, especially in cases where certain cables cause "bad sound".
I even allowed for such factors as dielectric absorption, conductance and RF-Shielding limiting RFI as "second order" effects.
I also postulated that there may exist "third order" differences, that is for example caused by metal purity, alloy/base metal chosen and so on.
For third order effects I cannot really postulate any reasonable explanation for audibility at this time (it can be made quite safely for the 2nd and 1st order effects though), however I am unwilling to reject the possibility of such existing on any evidence presented so far and am more inclined towards a position that leaves this whole are as unproven, but with a large body of anecdotal evidence for the presence of such third order effects.
I would probably expect tube amplifiers generally to by far less sensitive to speaker cable effects, but tube preamplifiers generally to be more sensitive to interconnect cable effects then their counterparts due to the obvious technical reasons.
I would suggest that we are quite safe to reject the hypothesis as quoted, though I would not safe to accept or reject the hypothesis that what I call third order effects are responsible for the remainder of the audible differences widely reported, or that other factors are responsible...
As others have reported here, I have too done trials with multiple cables build up to exactly the same geometry, same RLC parameters AND same second order parameters with respective parameters optimised to minimise any impact of first and second order effects on the signal (in this case RCA interconnects made with very low capacitance [< 10pF/m], very low DA [mostly air dielectric] AND with the same Neutrik Pro RCA Plugs on all cables.
The cables where visually identical, except for marking of A, B and C and where given to prospective buyers for audition, it was indicated that the cables would all cost the same and had only minor differences.
The only differences where the signal conductors materials (all bare wires with different conductor materials and different coatings or non).
At the time I had at least ten cases where the potential buyers all preferred ONE of the cables significantly and asked their cables to be made to this one pattern, not to the other, incidentally, they all also bought the cables, at a fairly high price for line level cables, voluntarily, without any heavy sales talk etc.
Ciao T
In an article on audio cables I wrote over a decade ago I called these "first order" effects and ascribed MOST gross subjective differences between cables of dramatically different construction and electrical parameters, especially in cases where certain cables cause "bad sound".
I even allowed for such factors as dielectric absorption, conductance and RF-Shielding limiting RFI as "second order" effects.
I also postulated that there may exist "third order" differences, that is for example caused by metal purity, alloy/base metal chosen and so on.
For third order effects I cannot really postulate any reasonable explanation for audibility at this time (it can be made quite safely for the 2nd and 1st order effects though), however I am unwilling to reject the possibility of such existing on any evidence presented so far and am more inclined towards a position that leaves this whole are as unproven, but with a large body of anecdotal evidence for the presence of such third order effects.
I would probably expect tube amplifiers generally to by far less sensitive to speaker cable effects, but tube preamplifiers generally to be more sensitive to interconnect cable effects then their counterparts due to the obvious technical reasons.
I would suggest that we are quite safe to reject the hypothesis as quoted, though I would not safe to accept or reject the hypothesis that what I call third order effects are responsible for the remainder of the audible differences widely reported, or that other factors are responsible...
As others have reported here, I have too done trials with multiple cables build up to exactly the same geometry, same RLC parameters AND same second order parameters with respective parameters optimised to minimise any impact of first and second order effects on the signal (in this case RCA interconnects made with very low capacitance [< 10pF/m], very low DA [mostly air dielectric] AND with the same Neutrik Pro RCA Plugs on all cables.
The cables where visually identical, except for marking of A, B and C and where given to prospective buyers for audition, it was indicated that the cables would all cost the same and had only minor differences.
The only differences where the signal conductors materials (all bare wires with different conductor materials and different coatings or non).
At the time I had at least ten cases where the potential buyers all preferred ONE of the cables significantly and asked their cables to be made to this one pattern, not to the other, incidentally, they all also bought the cables, at a fairly high price for line level cables, voluntarily, without any heavy sales talk etc.
Ciao T
Sy,
Sy, so far no-one has been able to demonstrate any number of things at particle level. Nor has anyone been able to reliable demonstrate the absence of different metals in cables being audible, at least not in a peer reviewed journal in a peer reviewed double blind test, though enough people have done their own testing, often blind, which suggests that there is an audible difference and that dull, stodgy, reliable, conventional engineering has gotten it likely as right as it had about that little invention of the bicyle repairmen Orville and Wilbur..
As far as conventional engineering goes, dull and stodgy at that, I had a great demonstration today of what that does in terms of reliability! A Toyota car (of very recent manufacturing and fresh from the 5,000 miles checkup too) had precisely the "no breaks, accelerator full" event that Toyota had been recalling cars a few years back.
It so happens the car was travelling downhill in a fairly tight curve (yes, that is double plus ungood). The speed with the lack of control over the car was quite scary and I normally scare worth a damn.
The driver managed by sheer luck to avoid the concrete blockhouse at the bottom of the hill on the side where the high speed was pushing the car and instead smashed through barriers and seriously damaged the cars right front bleeding speed off by smashing up the little flower patch in the middle of the road which ripped the wheel nearly off and helped the car to temporarily prove the theorem that "heavier than air" flight is indeed possible.
Gear set to park and the hand-break which I pulled on eventually got us to stop... To say the security people in that blockhouse where pissed over the flower patch and barrier and about having to jump aside (we nearly got one of the guys) until they heard the story would be putting it mildly.
Despite the rather large impacts along the way the airbags did not deploy and the computer seemed to show all the lights on the dash in a "tilt" response to all of this and was sulking (and not deploying the f..king airbags).
Due mostly to luck we all walked away with only minor contusions, concussions and scrapes. Had we hit the concrete blockhouse, who knows...
All in all a fun-filled afternoon full of thrill rides, all courtesy of dull, stodgy, "reliable", conventional engineering. I guess I should send a thank you note!
Maybe those people freed up can work on finally fixing these problems in those Toyota Cars? Then I shall not complain that the question of which metal to use in audio cables remains unsettled a while longer.
Anyway, just because it seems inaccessible to the average engineer and was not thought at Uni does not mean a effect does not exist. I mean, heck, most engineers probably still believe in "Electrons"...
And all of us generally are lucky to be alive.
Seems I am rather using up those nine lives I have as a cat though, counting NDE's since that time falling from a tree at age six I think I'm down around seven of those nine lives, I think I need to slow down some.
Ciao T
Sy, so far no-one has been able to demonstrate any number of things at particle level. Nor has anyone been able to reliable demonstrate the absence of different metals in cables being audible, at least not in a peer reviewed journal in a peer reviewed double blind test, though enough people have done their own testing, often blind, which suggests that there is an audible difference and that dull, stodgy, reliable, conventional engineering has gotten it likely as right as it had about that little invention of the bicyle repairmen Orville and Wilbur..
As far as conventional engineering goes, dull and stodgy at that, I had a great demonstration today of what that does in terms of reliability! A Toyota car (of very recent manufacturing and fresh from the 5,000 miles checkup too) had precisely the "no breaks, accelerator full" event that Toyota had been recalling cars a few years back.
It so happens the car was travelling downhill in a fairly tight curve (yes, that is double plus ungood). The speed with the lack of control over the car was quite scary and I normally scare worth a damn.
The driver managed by sheer luck to avoid the concrete blockhouse at the bottom of the hill on the side where the high speed was pushing the car and instead smashed through barriers and seriously damaged the cars right front bleeding speed off by smashing up the little flower patch in the middle of the road which ripped the wheel nearly off and helped the car to temporarily prove the theorem that "heavier than air" flight is indeed possible.
Gear set to park and the hand-break which I pulled on eventually got us to stop... To say the security people in that blockhouse where pissed over the flower patch and barrier and about having to jump aside (we nearly got one of the guys) until they heard the story would be putting it mildly.
Despite the rather large impacts along the way the airbags did not deploy and the computer seemed to show all the lights on the dash in a "tilt" response to all of this and was sulking (and not deploying the f..king airbags).
Due mostly to luck we all walked away with only minor contusions, concussions and scrapes. Had we hit the concrete blockhouse, who knows...
All in all a fun-filled afternoon full of thrill rides, all courtesy of dull, stodgy, "reliable", conventional engineering. I guess I should send a thank you note!
Maybe those people freed up can work on finally fixing these problems in those Toyota Cars? Then I shall not complain that the question of which metal to use in audio cables remains unsettled a while longer.
Anyway, just because it seems inaccessible to the average engineer and was not thought at Uni does not mean a effect does not exist. I mean, heck, most engineers probably still believe in "Electrons"...
And all of us generally are lucky to be alive.
Seems I am rather using up those nine lives I have as a cat though, counting NDE's since that time falling from a tree at age six I think I'm down around seven of those nine lives, I think I need to slow down some.
Ciao T
Hi,
Expense was middeling, exotic? I don't know, depends on your definition. I bought it from a Biotech Research supply house as "scientific wire" (it even says so on the reel).
So the choice of the customers agreed with science, as they selected "scientific wire" as preferable to "unscientific wire".
BTW, the customers had no non-destructive way to open the cables to see what material was used, due to their construction and non destroyed the cables.
I got at least 10/10 results (possibly as many as 15 Customers), which analysed according to classic statistics with a significance of .05 makes it a significant result, incidentally.
Ciao T
Expense was middeling, exotic? I don't know, depends on your definition. I bought it from a Biotech Research supply house as "scientific wire" (it even says so on the reel).
So the choice of the customers agreed with science, as they selected "scientific wire" as preferable to "unscientific wire".
BTW, the customers had no non-destructive way to open the cables to see what material was used, due to their construction and non destroyed the cables.
I got at least 10/10 results (possibly as many as 15 Customers), which analysed according to classic statistics with a significance of .05 makes it a significant result, incidentally.
Ciao T
Scientific wire! Gotta get some of that. 
Sounds like an interesting test, you should write it up in detail and maybe start a thread. The identities of the materials don't have to be revealed, if you need to keep a secret.
Seems like you had way too much excitement today. Glad you're OK. Time to kick back with a drink. I've lost steering at high speed (link broke), it's a very scary feeling to no longer control the car.
Sounds like an interesting test, you should write it up in detail and maybe start a thread. The identities of the materials don't have to be revealed, if you need to keep a secret.
Seems like you had way too much excitement today. Glad you're OK. Time to kick back with a drink. I've lost steering at high speed (link broke), it's a very scary feeling to no longer control the car.
Duh, just as i was about to ask you out on a Guinness stout match, winner gets to shove the other cat's head down the toilet bowl.
Hi,
It's the name of company that makes it, actually.
I did that in 2004 or so for reasons of my own, and not as such as a test for metal audibility. Many of my blind tests are like that, they answer questions I have at the time, in my ways, to my satisfaction, without excessive scientific rigor, they are not really intended for publication.
So let's count it as more anecdotal evidence, shall we?
Thanks for the concern. I'll open a little bottle of red in a while.
BTW, the original cable post was on my screen in preview when I left to go and quickly do something with the real estate agent who drove, down the hill...
To be honest, my legs and hands stopped shaking around 10 seconds after I got out of the car, not that exciting really. It's just loosing these cat's lives so quickly that bothers me, I have decades ahead of me (only the good die young) and looks like I'll be out of luck pretty soon the rate I'm going.
Ciao T
Scientific wire! Gotta get some of that.
It's the name of company that makes it, actually.
I did that in 2004 or so for reasons of my own, and not as such as a test for metal audibility. Many of my blind tests are like that, they answer questions I have at the time, in my ways, to my satisfaction, without excessive scientific rigor, they are not really intended for publication.
So let's count it as more anecdotal evidence, shall we?
Thanks for the concern. I'll open a little bottle of red in a while.
BTW, the original cable post was on my screen in preview when I left to go and quickly do something with the real estate agent who drove, down the hill...
To be honest, my legs and hands stopped shaking around 10 seconds after I got out of the car, not that exciting really. It's just loosing these cat's lives so quickly that bothers me, I have decades ahead of me (only the good die young) and looks like I'll be out of luck pretty soon the rate I'm going.
Ciao T
I'm not sure what you mean by any of that, but I'm glad you survived your adventure courtesy of the cost-accountant mentality that seems to reign at many auto companies (so far, we've had excellent luck with Kia and Hyundai).
Scientific Wire, the name fooled me at first. I was thinking stuff like Keithley's exotic low noise tri-ax, etc. In any case I will be able to compare the 00 zip cord to that multistrand experiment I mentioned last month. BTW Thorsten I decided to only do your suggested arrangement with a little 100 hole PC board termination. The experiment was bundling 10 10 wire teflon ribbon cables into a square array. Thorsten recommended the totally alternating arrangement, which I think maximizes C and minimizes L. To be fair I should compute the exact equivalent guage zip cord and use equal lenghts.
Scott,
Actually the test has gotten flipped! I mention to some tweaky folks I have a method to measure resistor distortion, excess noise and thermo electric effects and their response is that they just use their ears and don't need no stinkin test, or equivalent. Then they ask about how their favorite type fared! Turns out they all ask about the same four resistors types, all of which measured very very well.
Anecdotal.. yes, but it is still interesting!
SY
I think there are some issues that need to be cleared up. As I suspect you know there is the critical band theory of hearing and to completely over simplify things there are about 50 bands that we use to receive sound.
So if for example you have a signal at 70 db centered around 50 hertz and add a secondary tone at 60 db 50 hertz even in an A/B comparison that is below the perception threshold. If you look at the Fletcher Munson curves and you understand the two signals (random phase) do not add up to a single db level increase.
If you did the same for any two signals in the same critical band you would at the most sensitive bands detect a difference when the combined level rose by around 1 db. (Not gonna argue with the exact threshold but some would go down to .25 db.) However if you have a primary signal around 50 hertz and a secondary signal at 3000 hertz there would be virtually no masking. If you look at the F/M curves you would see a tremendous difference in sensitivity. You also would pick up at least another 30 db from the band filtering action. (Again some make this number much higher.)
Now If we look at musical instruments, virtually no interesting musical timbre is a pure sine wave. Instrument makers designed their toys to have harmonics. The most common are of course second and third. Pianos for example have felted hammers to reduce the higher order harmonics. Now with second and third being generated you also can get fourth, fifth and ninth. Seventh is considered one of the non musical harmonics, as is eleventh and most of the higher orders.
I picked ninth as even though it can occur in musical instruments it is far enough from the fundamental to allow the ear's mechanism to show it's filtering.
The other important issue is musical energy level. The most music energy is found around 150 to 300 hertz (Again some folks will argue the exact range.) It then rolls off about 3 db per octave above and below this. (A.S.F.W.A.T.E.R.) So when you combine the F/M curves with the energy in music and the ear's filter ability there is reasonable research to explain the ability to perceive high order distortion and also why masking of similar spectra signals occurs.
The perception of the higher order annoyance may be biological or cultural, as not all musical instruments are made the same.
24 Bits!
The thermal noise level of a high quality microphone is around -134 db re 1mw/600 ohm voltage level. (A.S.F.W.A.T.E.R. 132!) A high quality analog mixing console will do +24 minimum output that is 158 db or 26 bits+ (but not 27) !
In live music the console operator will turn things up and down in level, so much of the range is actually used. However the power amplifiers are often only around 110 db S/N. But in a large system they are bandwidth limited and used in groups of 100 or more! So the ultimate S/N may approach 140 db! However as there is a crowd at such applications so you will never really hear that.
Now if anyone actually has a 24 bit converter that will do 100 KSPS please let me know.
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Ed,
Actually, "common" capacitor microphones used for recording have between 26 to 30dBA self noise, around 10mV output at 94dB SPL.
Few of those microphones will handle much more than 130dB and to be honest, to get those 130dB you need to shove the mike right into a trumpet, no minimalistic 2-Mike arrangements.
At the average mike positions I used to use classical orchestras at ffff used to hit mid 90's dB in average, with around 15dB crest factor. So we are talking about around 110dB peak with 26dBA noisefloor, or around 84dBA dynamic range, the way we used to characterise it in these old, long forgotten analogue days when we actually measured stuff, instead of making up the milkmaid numbers.
Then again, ribbon mikes with the right transformers could produce lower noise, if one really insisted...
Ciao T
Actually, "common" capacitor microphones used for recording have between 26 to 30dBA self noise, around 10mV output at 94dB SPL.
Few of those microphones will handle much more than 130dB and to be honest, to get those 130dB you need to shove the mike right into a trumpet, no minimalistic 2-Mike arrangements.
At the average mike positions I used to use classical orchestras at ffff used to hit mid 90's dB in average, with around 15dB crest factor. So we are talking about around 110dB peak with 26dBA noisefloor, or around 84dBA dynamic range, the way we used to characterise it in these old, long forgotten analogue days when we actually measured stuff, instead of making up the milkmaid numbers.
Then again, ribbon mikes with the right transformers could produce lower noise, if one really insisted...
Ciao T
That would assume the inputs see no gain. Put a 40dB preamp on the mike and now you have 118dB. Of course I have no idea if you are talking about spot noise, A weighted rms, or what. A moderately large digital recorder company posted pictures of highly averaged long FFT's of their A/D response and claimed -150dB noise floor.
Yes the noise level is for a ribbon or equally low output impedance microphone.
The gain is operator controlled. So in theory when there is no signal there is no gain. There also may be multiple microphones in use so the final s/n may go up!
In most of the large systems I do the final S/N is greater than 110 db.
If there is perceived noise out of the loudspeakers in the empty room when there is no signal source that is a bad S/N ratio. If you put your head in the same place during use, well you won't have to worry about perceiving low levels ever again!
Now is there anyone who wants to argue 16 bits is enough? It really doesn't work for even electronic reverb systems in performing arts spaces.
My design goal for sound system components is 160 db S/N. If you set your sights low... vs. setting them high. Now if I ever get there...
Scott, A weighted fast response IEC standard measurement is useful for the low level signals such as noise. Flat weighting is used for theoretical nonsense and assumed to be BW limited to 15,700 hertz.
The U47-FET lists 18dBA, 8mV/Pa, and 137dB SPL at .5% THD. A 34mm capsule can be made to have 5-7dBA self noise at about the physics limit.
Does anyone have a link to the self noise of a classic ribbon? I could only find Audio Technica's at 22dB.
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