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  1. #61

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    Quote Originally Posted by jcandy View Post
    The Daytons (5%) were the least expensive of the capacitors I tested. They did quite well (third out of nine). I am still collecting capacitors and am refining the test setup (I want to do multiple impedance sweeps with different shunt resistors). But in this preliminary test Jantzen, Erse, Dayton were 1,2,3. The worst were the Gen 1 Sonicaps (measuring 8.025uF versus the rated 8.2), at more than 4x the cost of the Daytons. Obviously, some of this variation is statistical, so in stage 2 of the test I will compare ensembles of the same capacitor to measure unit variation.

    My makeshift kitchen "laboratory".

    When I was doing the inductor and circuit board upgrades on my SDA CRS+'s, I took the opportunity to do further measurements on the 12 uF and 20 uF capacitors used in their crossovers.

    For the 20 uF capacitors, my findings concurred with jcandy's that the Sonicap's had the most deviation from nominal value. However, there are other factors which affect a capacitor's performance in an audio circuit besides deviation from rated value. Three of these are transient response, noise performance and dissipation factor. I would expect that anyone doing a serious quantitative study of capacitor performance in stereophonic audio circuits would demonstrate due regard for these parameters. My research indicates that there is a link between these parameters and imaging and spatial properties.

    With the 20 uF caps, the Sonicaps had the most deviation from nominal value (20.73 uF), yet sounded the best. The stock electrolytics measured the closest to nominal value (20.13 uF), yet sounded the worst. Sonicap's had the best transient response and noise performance, as measured with an oscilloscope, and the lowest power dissipation factor, as measured with an LCR meter. The stock electrolytics had the worst performance in these three categories.

    In this study, the 12 uF and 20 uF capacitors which have been used in three pairs of CRS+'s speakers were evaluated. The 20 uF capacitors were: (1) stock electrolytics, (2) Solen PB series, (3) AudioCap PPMF series, (4) Sonicap Gen I. The 12 uF capacitors were: (1) stock mylar, (2) Clarity Cap SA series, (3) AudioCap PPMF series, (4) Sonicap Gen I.

    Quote Originally Posted by jcandy View Post
    Of course, if you value something other than rated capacitance from your capacitor, then you can discount my results.
    I value a capacitor doing the least amount of damage possible to the MUSIC signals passing through it. To that end, the type and quality of dielectric material and construction technique play important roles in minimizing signal losses.

    It is not clear to me why anyone would think that a complete understanding of an electronic component's performance can be gained simply by measuring its rated value. Shouldn't we be primarily concerned with how a signal looks (i.e. maintains integrity) after it passes through a component?

    Similar to the results with my SDA inductor replacements, I found a direct correlation was between a capacitor's transient response, noise performance, dissipation factor and its sound quality relative to other capacitors. The AudioCap PPMF's were close in measurement and in sound quality to the Sonicap Gen I's, but the Sonicap's provided better spatial rendering, image weight, overall detail and bass performance.

    As I noted in my SDA SRS 1.2TL Sonicap upgrade thread (here), Soniccraft's owner, Jeff Glowaki, tried to discourage me from replacing the AudioCap's with Sonicaps. He specifically said that the Sonicap replacement wouldn't be "worth the money" and he specifically recommended bypassing the AudioCaps with small value Sonicaps. However, I politely declined his more cost effective recommendations in favor of consideration for the favorable experience reports of other speaker owners who had made the switch.

    I would add the caveat that higher quality capacitors with higher measured performance may not result in an audible difference or improvement in some audio equipment. This is particularly true with high quality capacitors constructed of the same dielectric material.
    Last edited by DarqueKnight; 04-07-2011 at 04:46 PM.
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  2. #62

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    I am quite certain there is nothing you can teach me. Your type of lecturing and lack of real world experience is certainly incongruent with my experiences and knowledge. You certainly have a right to your opinions, tests and conclusions. But that doesn't mean I have to agree or even entertain the results of your flawed hypothesis.

    Just because you can act arrogant doesn't mean what you are peddling has any more merit than anything else posted on this audio board.

    With that I'm done here because we are on opposite sides, and the chasm will never be bridged.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

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  3. #63

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    Quote Originally Posted by jcandy View Post
    How do you account for the fact that despite stories like this, no differences are heard once the testing is truly blind?

    The results show that people cannot even do better than random, and the fact is that the Daytons are as good (or better) than much more expensive caps in this application.
    I was not aware of this test until you mentioned it and I have not read it. Was the test conducted under realisitic stereophonic listening conditions? If so, I would be interested in reading it.
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
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  4. #64

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    Thanks for the write up DarqueKnight. It is nice to see someone actually do all the research needed including listening to them.

    Amazing!
    Quote Originally Posted by Timothy Smith View Post
    WOW!

    That's like working your way through Katie Perry in order to get to Rosie O'Donnell.

  5. #65

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    Quote Originally Posted by jcandy View Post
    Yes, all speakers are the same.
    JC, I'm relatively new here. I have been following what you post with an open mind, always giving you the benefit of the doubt when I wondered if what you were saying was in line with what makes common sense. With that one statement you have changed the way I think about your posts. If you think all speakers are the same you can't be thinking rationally and are indeed only looking for an argument. You won't get that argument from me so there is no need for a reply.
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  6. #66

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    Quote Originally Posted by Joe08867 View Post
    It is nice to see someone actually do all the research needed including listening to them.
    I actually haven't finished this project yet. Some of the instruments I used at home do not have the sensitivity of laboratory grade instruments, although good results were obtained. Therefore, I will be repeating the measurements in my lab at work.

    Another question I want to investigate is whether performance tests on capacitors are meaningful if the capacitors are not yet burned in. One thing that I did with the inductor upgrades that I have not yet done with capacitor upgrades was taking measurements prior to and after burn in.

    More later...
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
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  7. #67

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    Quote Originally Posted by DarqueKnight View Post
    I actually haven't finished this project yet. Some of the instruments I used at home do not have the sensitivity of laboratory grade instruments, although good results were obtained. Therefore, I will be repeating the measurements in my lab at work.

    Another question I want to investigate is whether performance tests on capacitors are meaningful if the capacitors are not yet burned in. One thing that I did with the inductor upgrades that I have not yet done with capacitor upgrades was taking measurements prior to and after burn in.

    More later...
    You mean you can't sit at home with consumer grade equipment and take a couple uncorrelated measurements over a few days and have reliable results? Who would have even entertained that aspect of the experiment being of upper most importance; and you listened to them? I don't see you jumping to any hasty conclusions.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

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  8. #68

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    Quote Originally Posted by heiney9 View Post
    You mean you can't sit at home with consumer grade equipment and take a couple uncorrelated measurements over a few days and have reliable results?
    That depends on what you are measuring. In the case of high quality metalized polypropylene film capacitors, the measurable and sonic differences between brands are often subtle and more sensitive measuring instruments may be required. I was intrigued by the fact that the AudioCap PPMF caps measured so closely to the Sonicap Gen I's, yet there were immediately apparent sonic differences between them.

    In the case of the Solen 14 AWG 16 mH inductors and the Northcreek 14 AWG 16 mH inductors used in my CRS+'s (report here), the measured and sonic differences between them were so glaring that I had no reason to take them to the lab. The Solen and Northcreek inductors had nearly the same deviation from rated inductance value, nearly the same measured DCR and nearly the same size and weight. Yet, the Solen inductors sounded and measured much better right out of their shipping boxes than the Northcreek inductors did after over 100 hours of burn in.

    Quote Originally Posted by heiney9 View Post
    ...and you listened to them?
    Of course I listened to them. You can't measure something and know how it will sound. That is like saying you can read a cake recipe and know how the cake will taste. Who in their right mind would say, or even imply, such an absurdity?

    Measurements provide some design and evaluative insight, but just as the proof of the cake is in the eating, the proof of the stereophonic audio is in the listening.

    Such Good Science.
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  9. #69

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    Quote Originally Posted by TennMan View Post
    JC, I'm relatively new here. I have been following what you post with an open mind, always giving you the benefit of the doubt when I wondered if what you were saying was in line with what makes common sense. With that one statement you have changed the way I think about your posts.
    That "one statement" was (obviously, I thought) a joke in response to a poster who suggested that I think all speakers are the same. Obviously, there are two types of speakers, the left and right one.

  10. #70

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    Quote Originally Posted by jcandy View Post
    That "one statement" was (obviously, I thought) a joke in response to a poster who suggested that I think all speakers are the same. Obviously, there are two types of speakers, the left and right one.
    OK. Fair enough. If I could I would edit my last post to remove the first part and have it simply say: "(you) are indeed only looking for an argument. You won't get that argument from me so there is no need for a reply."
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  11. #71

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    Quote Originally Posted by DarqueKnight View Post
    For the 20 uF capacitors, my findings concurred with jcandy's that the Sonicap's had the most deviation from nominal value.
    Interesting. Over what frequency range?

    Quote Originally Posted by DarqueKnight View Post
    However, there are other factors which affect a capacitor's performance in an audio circuit besides deviation from rated value. Three of these are transient response
    A transient is a sum of fourier harmonics, so a frequency-dependent sweep of the impedance is in effect a complete transient analysis.

    Quote Originally Posted by DarqueKnight View Post
    noise performance
    Although I have heard of capacitative noise reduction, I was not aware that noise was ever a problem with audio capacitors. Frequency-dependent measurements show an extremely noiseless response in all the poly. caps I measured.

    Quote Originally Posted by DarqueKnight View Post
    and dissipation factor.
    which is a combination of series resistance, leakage (parallel) resistance, and dielectric loss. All can be backed out of my impedance scans with some clever curve-fitting using well-known circuit models.

    Quote Originally Posted by DarqueKnight View Post
    With the 20 uF caps, the Sonicaps had the most deviation from nominal value (20.73 uF), yet sounded the best.
    I think the point is, how did the actual 20Hz-20kHz response look? This scan will effectively contain all required information about transient response and dissipation factor. In my scans, the metalized poly caps were very flat over the entire FR. In essence, they were nearly all perfect capacitors, only they differed in actual capacitance. As FGTV suggested earlier, L-R driver impedance differences are larger than impedance anomalies caused by different poly caps.

  12. #72

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    Default Polk tweeters any originals good?

    I've been doing a lot more reading here than posting but I need to ask this question. Polk sold a lot of speakers even with the 1000, 2000 and 2500 tweeters that have been trashed and condemned in several posts. How did they do that? Were all of us who bought these speakers back in the 80s and early 90s completely tone deaf? My Monitor 10s and 5s have the 2500 tweeters and they sound good to me and I don't intend to replace them with the RDO 198s that so many here think are much better. I realize that improvements can be made but how do improvements turn these original tweeters into something people can't even listen to?


    Gotta stop reading here so much or soon I'll be convinced to toss out all my old Polks and buy the latest and greatest which will be out soon
    I'll just continue to enjoy what I have along with a little Makers Mark which can smooth out the highs of the big Sansuis even.
    TO ERR IS HUMAN. TO FORGIVE IS CANINE.

  13. #73

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    Quote Originally Posted by DON73 View Post
    I've been doing a lot more reading here than posting but I need to ask this question. Polk sold a lot of speakers even with the 1000, 2000 and 2500 tweeters that have been trashed and condemned in several posts. How did they do that? Were all of us who bought these speakers back in the 80s and early 90s completely tone deaf? My Monitor 10s and 5s have the 2500 tweeters and they sound good to me and I don't intend to replace them with the RDO 198s that so many here think are much better. I realize that improvements can be made but how do improvements turn these original tweeters into something people can't even listen to?


    Gotta stop reading here so much or soon I'll be convinced to toss out all my old Polks and buy the latest and greatest which will be out soon
    I'll just continue to enjoy what I have along with a little Makers Mark which can smooth out the highs of the big Sansuis even.
    Ford and GM sold a lot cars in the 70's and 80's.........aren't the current offerings better in every way? Technology moves rapidly and improvements are made. Why not take advantage of those improvements? Also remember gear and source material is different, most likely better than it was 20 years ago.

    Don't know about you but I think a Chrysler 300 is much better than a Reliant K car.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

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    Quote Originally Posted by DON73 View Post
    I've been doing a lot more reading here than posting but I need to ask this question. Polk sold a lot of speakers even with the 1000, 2000 and 2500 tweeters that have been trashed and condemned in several posts. How did they do that? Were all of us who bought these speakers back in the 80s and early 90s completely tone deaf? My Monitor 10s and 5s have the 2500 tweeters and they sound good to me and I don't intend to replace them with the RDO 198s that so many here think are much better. I realize that improvements can be made but how do improvements turn these original tweeters into something people can't even listen to?
    I did FR comparisons between SL2000T and RDO-194 in the SDA2B and there was about as much difference as taking the grills on and off, and well within the realm of "preference" versus better/worse. Of course the mystics started screaming bloody murder.

  15. #75

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    Quote Originally Posted by jcandy View Post
    Although I have heard of capacitative noise reduction, I was not aware that noise was ever a problem with audio capacitors.
    This explains a lot. Thanks.
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  16. #76

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    Quote Originally Posted by jcandy View Post
    Although I have heard of capacitative noise reduction, I was not aware that noise was ever a problem with audio capacitors.
    While I'm aware of thermal(Johnson)noise that can be generated in resistors ,noise as it relates to high quality film capacitors is new terminology to me as well.I would be interested in the methodology used to quantify this aspect of capacitor performance
    As FGTV suggested earlier, L-R driver impedance differences are larger than impedance anomalies caused by different poly caps.
    While thats also likely the case my comment was in reference to frequency response.Even different samples of very good tweeters can have variances in their frequency responses of >1db over parts of their range.If significant differences occur near the crossover frequency or in the stop band then IMO they would swamp any response errors that might occur from using a (Jcandy's example) 8.025 uf cap in place of an 8.2 uf.
    Last edited by FTGV; 04-07-2011 at 09:54 PM.

  17. #77

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    Quote Originally Posted by DarqueKnight View Post
    This explains a lot. Thanks.
    So, can you elaborate?

  18. #78

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    Quote Originally Posted by heiney9 View Post
    Ford and GM sold a lot cars in the 70's and 80's.........aren't the current offerings better in every way? Technology moves rapidly and improvements are made. Why not take advantage of those improvements? Also remember gear and source material is different, most likely better than it was 20 years ago.

    Don't know about you but I think a Chrysler 300 is much better than a Reliant K car.

    H9



    I understand that improvements are being made constantly but I can't see why an RDO tweeter that may be better can turn the 2500 into trash.
    I'll reserve comments on the Chrysler 300
    TO ERR IS HUMAN. TO FORGIVE IS CANINE.

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    Anyone who says "trash" is overstating. The SL2500 and 3000 were much better than the sl2000. The RD0's are better yet than the all of them but to a lesser degree between the 2500/3000 than the sl2000. Some of the issues with the sl2000 simply have to do with age exacerbating the degradation of sound.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

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  20. #80

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    Quote Originally Posted by troll
    Although I have heard of capacitative noise reduction, I was not aware that noise was ever a problem with audio capacitors.
    From the pages at Sonic Craft by one of the most respected authorities on all things capacitor related......

    The Sonicap is well balanced and true to the source. The word "neutral" is so loosely (and incorrectly) used, that I prefer the term "balanced". While capacitors suffer from more noise (high distortion) than most audio components, the Sonicap exhibits very low noise and parasitics.
    'Political Correctness'.........defined

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    Quote Originally Posted by F1nut View Post
    From the pages at Sonic Craft by one of the most respected authorities on all things capacitor related......
    The Sonicap is well balanced and true to the source. The word "neutral" is so loosely (and incorrectly) used, that I prefer the term "balanced". While capacitors suffer from more noise (high distortion) than most audio components, the Sonicap exhibits very low noise and parasitics.

    LOL. Please explain what "noise" is, in the above context. Is it any non-capacitative effect? Is it a specific non-capacitative effect like leakage resistance? It is gnome yodelling?

    Do tell!

  22. #82

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    Mechanical resonance, which you would have known if you knew a damn thing about capacitors in the first place, sport!
    'Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."

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    Quote Originally Posted by F1nut View Post
    Mechanical resonance, which you would have known if you knew a damn thing about capacitors in the first place, sport!
    I know quite a bit about capacitors, actually. It wonder, why was the completely non-specific word "noise" used rather than "mechanical resonance" or perhaps just resonance. I think its because all you capacitor mystics spent too much time at frat parties and not enough time in physics class. I strongly suspect you don't really know what your favourite power-words actually mean.

    Here are the facts: the recent work on mechanical resonance in metalized film capacitors (by Duncan, et. al. AES 2009) is simply a measurement of the vibration of the capacitor itself, NOT a resonance that occurs in the audio signal. If you think there is any actual scientific work that connects the mechanical resonance(s) of a film capacitor to some anomaly in the capacitors capacitance, please point it out to me.

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    Quote Originally Posted by F1nut View Post
    Mechanical resonance, which you would have known if you knew a damn thing about capacitors in the first place, sport!
    Oh F1, is it really true that an electrical part like a capacitor would have some mechanical resonance that would introduce audible distortion? It's hard to believe because it sounds so, so, so, mystical.

    I vividly and fondly recall that, when I preparing to do my first speaker crossover modification, a capacitor mystic earnestly abjured me to "strap down" the big, juicy film capacitors that would be replacing those nasty old electrolytics.

    See below how I have held to that teaching to this very day? The crossovers of my venerable SDA SRS 1.2TL's are full of big, juicy Sonicap polypropylene film capacitors which are not only strapped down, but are also secured to the board with Scotch Heavy-Duty Mounting Tape (the gray stuff peeking out from under the caps).


    Little juicy straps for big juicy caps!

    With regard to alleged capacitor mysticism, there are a few papers on capacitor noise that the interested reader may want to review. The first paper, by Dr. Philip Duncan et al, is an AES convention paper that offers a fairly mathematically rigorous treatment of the subject: "Forces in cylindrical metalized film audio capacitors". This paper can be accessed free of charge at this link:


    Now, please be advised that AES convention papers are not rigorously peer reviewed. Nevertheless, the Duncan et al paper seems to go to some length to mathematically justify their position.

    The Duncan paper also cites several relevant references from IEEE journals. IEEE journals are very rigorously peer reviewed.

    Now, I fully realize and understand that some people may not want to consider the information provided by the delusional capacitor mystics at Club Polk regarding capacitor noise. The link below provides Dr. Philip Duncan's contact information at the University of Salford, UK. He seems to have done some credible research in this area.


    Quote Originally Posted by jcandy View Post
    I know quite a bit about capacitors, actually. It wonder, why was the completely non-specific word "noise" used rather than "mechanical resonance" or perhaps just resonance. I think its because all you capacitor mystics spent too much time at frat parties and not enough time in physics class. I strongly suspect you don't really know what your favourite power-words actually mean.
    This statement reflects poorly on your character. Why criticize us for being non-specific if we were not in error? Some things are assumed to be well understood by those who purport to have expertise in a technical area and who disparage others who are alleged to engage in audio mysticism.

    Quote Originally Posted by jcandy View Post
    Here are the facts: the recent work on mechanical resonance in metalized film capacitors (by Duncan, et. al. AES 2009) is simply a measurement of the vibration of the capacitor itself, NOT a resonance that occurs in the audio signal. If you think there is any actual scientific work that connects the mechanical resonance(s) of a film capacitor to some anomaly in the capacitors capacitance, please point it out to me.
    We capacitor mystics are not concerned with anomalies in a capacitor's capacitance, but rather, with a capacitor introducing anomolies in a music signal's waveform.

    Here is a quote from the Duncan AES 2009 paper (p. 9) that appears to contradict your statement that capacitor mechanical resonance does not affect audible frequencies:

    "Experiments have been carried out where capacitors have undergone rapid discharge with the discharge voltage and acoustic emissions measured and recorded as a function of time. Analysis of the time domain data shows mechanical resonance peaks in the upper audio frequency band."

    From p. 7:

    "These results show a clear resonant peak for each of the capacitors in the upper audio frequency band between 14kHz and 22kHz indicative of a mechanical resonance at that frequency."



    More later....

    Such Good Science


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    Such Good Mysticism Too!!!
    Last edited by DarqueKnight; 04-08-2011 at 01:19 PM.
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    Quote Originally Posted by DarqueKnight View Post
    Here is a quote from the Duncan AES 2009 paper (p. 9) that appears to contradict your statement that capacitor mechanical resonance does not affect audible frequencies:

    "Experiments have been carried out where capacitors have undergone rapid discharge with the discharge voltage and acoustic emissions measured and recorded as a function of time. Analysis of the time domain data shows mechanical resonance peaks in the upper audio frequency band."
    You don't understand the paper at all, do you? The measurements of mechanical resonance are measurements of the "mechanical vibrations of the capacitor body" (page 2). There is no actual link demonstrated between this mechanical resonance, and the electrical properties of the capacitor.

    Aside from the mechanical measurements of the vibrating capacitor, they performed electrical measurements (the usual ESR and dissipation factor), with the conclusion "the measurements were carried out using a Wayne Kerr 6430B component analyzer and all results obtained showed very similar trends with little or no deviation from theoretical predictions." Big surprise there, hey?

    Get yourself a cup of coffee, sit down, and actually read the paper. Then we can talk about the Emperor and his clothes.
    Last edited by jcandy; 04-08-2011 at 01:50 PM.

  26. #86

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    Quote Originally Posted by jcandy View Post
    You don't understand the paper at all, do you? The measurements of mechanical resonance are measurements of the "mechanical vibrations of the capacitor body" (page 2). There is no actual link demonstrated between this mechanical resonance, and the electrical properties of the capacitor.

    Aside from the mechanical measurements of the vibrating capacitor, they performed electrical measurements (the usual ESR and dissipation factor), with the conclusion "the measurements were carried out using a Wayne Kerr 6430B component analyzer and all results obtained showed very similar trends with little or no deviation from theoretical predictions." Big surprise there, hey?

    Get yourself a cup of coffee, sit down, and actually read the paper. Then we can talk about the Emperor and his clothes.
    The only "big surprise" is that when you are clearly shown to be wrong, you still cling to your "beliefs" with religious fervor and tenacity.

    CLARIFICATION: The underlined quote you cited above is not from the Duncan et al 2009 paper. It is from Duncan et al 2008, "Audio capacitors. Myth or reality?" Please try to keep your references straight. Otherwise, it makes it appear that you really didn't actually read the paper(s).

    You specifically said, regarding the Duncan 2009 paper:

    Quote Originally Posted by jcandy View Post
    Here are the facts: the recent work on mechanical resonance in metalized film capacitors (by Duncan, et. al. AES 2009) is simply a measurement of the vibration of the capacitor itself, NOT a resonance that occurs in the audio signal.
    I specifically pointed out:

    Quote Originally Posted by DarqueKnight View Post
    Here is a quote from the Duncan AES 2009 paper (p. 9) that appears to contradict your statement that capacitor mechanical resonance does not affect audible frequencies:

    "Experiments have been carried out where capacitors have undergone rapid discharge with the discharge voltage and acoustic emissions measured and recorded as a function of time. Analysis of the time domain data shows mechanical resonance peaks in the upper audio frequency band."

    From p. 7:

    "These results show a clear resonant peak for each of the capacitors in the upper audio frequency band between 14kHz and 22kHz indicative of a mechanical resonance at that frequency."
    Quote Originally Posted by jcandy View Post
    You don't understand the paper at all, do you?
    It is obvious that it is you who does not understand the paper. You can engage in all the face-saving, side-stepping, red herring tactics you want, but the facts are:

    1. You clearly did not have any knowledge, and understanding, of the noise generating mechanisms in capacitors until it was specifically pointed out to you. This was verified by your rash erroneous assumption that the authors did not correlate mechanical vibration to audible noise.

    2. The authors show a clear link between mechanical noise in a capacitor and the creation of audible noise, contrary to your erroneous statement that they did not address this. Did YOU read the paper?

    3. For audio applications, we can assume that established, reputable manufacturers of capacitors know how to make them with good electrical properties. Therefore, as long as the capacitor is within its tolerance from rated value we do not need to be overly concerned with the electrical properties of the capacitor. We do need to be concerned about the audible effects of those electrical properties. If you are a music lover, you should have some concern about how the noise characteristics of a capacitor will affect the music signals passing through it.

    4. Contrary to your "beliefs", there are other things which affect a capacitor's sound performance in addition to its rated value.

    5. With regard to what the authors wanted to accomplish with the paper, they are quite clear (p. 2):

    "This work presented in this paper has focused on the use of metalized film capacitors in loudspeaker crossover applications and one of the main findings has been that the capacitors used in crossover applications exhibit varying degrees of mechanical resonance. Duncan and Dodds in [6] have shown that the resultant acoustic emissions from some of the capacitors under ac current conditions have been found to be significant, and detrimental to the overall reproduced sound quality."

    "...discussions with loudspeaker manufacturers, and anecdotal evidence from within the industry suggested that mechanical vibration and resonance phenomena in crossover capacitors has a detrimental effect on the quality of the reproduced sound. This has been confirmed by the authors in a series of detailed subjective listening tests, the results of which are presented in [6]."

    The conclusion section states (p. 9)

    "These results show a clear resonant peak for each of the capacitors in the upper audio frequency band between 14kHz and 22kHz indicative of a mechanical resonance at that frequency."

    Obviously, the authors of the paper are primarily concerned with the detrimental effects of capacitor mechanical vibration on SOUND QUALITY and not whether there is a link between mechanical vibration and the electrical properties of the capacitor.

    I think it is rather ironic that a paper that you offered (Duncan et al 2009) to supposedly debunk audiophile views of audible differences in capacitors actually strongly supports it.

    Question: You appear to believe that Duncan et al 2008, "Audio capacitors. Myth or reality?", also debunks the audiophile assertion that there are audible differences in capacitors. Is that your position?

    Do tell!!
    Last edited by DarqueKnight; 04-08-2011 at 03:18 PM.
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
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    Eh....Capacitors Sucks!

    So, how about helping the OP to recap his Monitor 5 & 7?

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    I think the OP ran for cover when he heard all the talk about trolls and mysticism......

    He probably thinks we practice the dark arts.
    Quote Originally Posted by Timothy Smith View Post
    WOW!

    That's like working your way through Katie Perry in order to get to Rosie O'Donnell.

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    Quote Originally Posted by megasat16 View Post
    Eh....Capacitors Sucks!
    I agree. Capacitors do suck up electrical charges.

    Quote Originally Posted by megasat16 View Post
    So, how about helping the OP to recap his Monitor 5 & 7?
    We are. The discussion of capacitor performance is pertinent to selecting an appropriate upgrade capacitor.

    Quote Originally Posted by Joe08867 View Post
    I think the OP ran for cover when he heard all the talk about trolls and mysticism......

    He probably thinks we practice the dark arts.
    Speaking of darque arts, Clarity Cap, a manufacturer of high end, high performance capacitors, offers the following technical report to bolster thier position concerning why you should invest in big, juicy, pricey audiophile grade kapaciters:



    Now, the weekend is here once again and I will be caught up in some leisure activies. I don't know if I will be able to pop in to continue our discussion over the weekend. If not, I'll see you guys on Monday.

    Don't y'all fight, now.:tongue:
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    We are. The discussion of capacitor performance is pertinent to selecting an appropriate upgrade capacitor.



    60+ posts and no more than 2 have been directed precisely at the OPs question. Just a pissing contest in which some posters do their best to insult and disrespect each other. The OP has 6 posts..........he probably won't be back. It's a little like third grade recess or when the teacher left the room. Some here need to grow up and act like adults.
    TO ERR IS HUMAN. TO FORGIVE IS CANINE.

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