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Burning in hi-pass capacitors

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  • Re: Burning in hi-pass capacitors

    Originally posted by bkeane1259 View Post
    Umm, Jensen maybe? Or are you saying Jantzen? Both have pretty good reputations for quality capacitors. I have read that the Jantzen crosscaps are not very good. I am extremely happy with the Jantzen Superior Z line.

    Everyone has an opinion. As we continue to discuss this, it really makes me curious to see what happens with the tests. Wish I had more time on my hands to get things rolling right away, but for sure we will get rocking on this next weekend.
    Here are some measurements that may shed some quantitative light on the Cross-Cap vs Superior Z-Cap discussion.

    Luckily, I had a 4.7 uF Jantzen MKP 400 V Cross-Cap and a 3.9 uF Jantzen 800 V Superior Z-Cap to test. I ran some special tests with my WT2. Not a megabuck test instrument, but a very effective one just the same. The test methodology is the subject of a forthcoming article in audioXpress magazine.

    Screenshots of the test output are below (thanks to some help from bkeane..). The test measures Capacitive reactance, phase, ESR and Capacitance from 10 to 20 kHz over 31 data points. The plots in the left window are impedance (red line) and phase (blue line) The best caps I've tested show phase at a nice flat line at the -90 deg level. Both of these do. I've seen full or 1/2 smile profiles in the blue line with vintage NPE's and other caps. Secondly, variation in the reading of phase and capacitance over the test freq. range is minimal in very good caps. To evaluate this, basic statistics are run on the phase and capacitance columnar data. I like to use coeficient of variation (st'd dev./ave) express as a % to quantify the variability. The cross cap phase was 0.52%, capacitance COV was 0.404%. The Superior Z-Cap was 0.28% and 0.38% - a little better. COV's on vintage NPE's and others's were typically well over 1% and some as high as 5%.
    Measurements taken with my TENMA LCR meter were 3.908 uF and 0.1% D.F. for the Superior Z-Cap and 4.805 uF and 0.1% D.F.

    The bottom line here is that both caps, though not identical in their capacitance, voltage values are never-the-less very close with respect to their variability.



    Last edited by carlspeak; 05-08-2011, 08:57 PM. Reason: p.s. added
    Live in Southern N.E.? check out the CT Audio Society web site.

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    • Re: Burning in hi-pass capacitors

      Originally posted by carlspeak View Post
      The cross cap phase was 0.52%, capacitance COV was 0.404%. The Superior Z-Cap was 0.28% and 0.38% - a little better. COV's on vintage NPE's and others's were typically well over 1% and some as high as 5%.
      Thanks for taking the time to run those measurements. I did DM you.

      Please correct me if I'm wrong. While you're saying that the Jantzen crosscap and Jantzen Super-Z measured similarly, you're also pointing out that some NPE's under this testing methodology are inferior to poly's? Is a capacitance COV of 5% HUGE and unacceptible if that cap is to be used in the hi-pass section of a speaker crossover?
      Bryan K.

      Midwest Audio Club

      Speedster | | The Wildeman | Sean's NLA Towers | , COUGAR II and | Triton | Lithium | J-Boom | Trym MLTL | Docere MLTL

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      • Re: Burning in hi-pass capacitors

        Originally posted by johnnyrichards View Post
        One thing that has to be done is to make sure the caps actually, you know, measure the same. Tolerances vary, and can impact things. I would guess that +/- 1% or less of each other would be adequate.
        As long as we are talking about metalized poly audio caps, I think this is the beginning and end of the whole debate. These caps tend to perform extremely well as "ideal" capacitors, but the actual capacitance can vary according to the tolerance. A 5% change may very well be audible in many cases. I have a sample "8.2 uF Gen 1 Sonicap" that is a nearly perfect 8.05 uF capacitor, not a nearly perfect 8.2 uF capacitor.
        Action speaks louder than words but not nearly as often. -- Mark Twain

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        • Re: Burning in hi-pass capacitors

          Originally posted by carlspeak View Post
          Luckily, I had a 4.7 uF Jantzen MKP 400 V Cross-Cap and a 3.9 uF Jantzen 800 V Superior Z-Cap to test. I ran some special tests with my WT2. Not a megabuck test instrument, but a very effective one just the same. The test methodology is the subject of a forthcoming article in audioXpress magazine.
          I have noticed that the measured capacitance (specifically at high frequency) varies a bit depending on the value of the shunt resistor used for the WT2 capacitance measurement. Have you tried repeating the measurement with a different shunt resistance?
          Action speaks louder than words but not nearly as often. -- Mark Twain

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          • Re: Burning in hi-pass capacitors

            Originally posted by jcandy View Post
            I have noticed that the measured capacitance (specifically at high frequency) varies a bit depending on the value of the shunt resistor used for the WT2 capacitance measurement. Have you tried repeating the measurement with a different shunt resistance?
            I didn't repeat the measurements on the Jantzen caps with different shunt resistors. But yes, the level of shunt resistance selected for the test should coincide with the level of uF being tested. I typically use 100 ohms. However, very low uF values require a much higher level of shunt resistance and the opposite for very high values of uF in order to get a good test result. The AE article discusses this.
            Live in Southern N.E.? check out the CT Audio Society web site.

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            • Re: Burning in hi-pass capacitors

              Originally posted by bkeane1259 View Post
              Thanks for taking the time to run those measurements. I did DM you.

              Please correct me if I'm wrong. While you're saying that the Jantzen crosscap and Jantzen Super-Z measured similarly, you're also pointing out that some NPE's under this testing methodology are inferior to poly's? Is a capacitance COV of 5% HUGE and unacceptible if that cap is to be used in the hi-pass section of a speaker crossover?
              I'm not saying COV's = or > 5% are unacceptable. Again, subjective assessment of the audio response is the final arbitor. I'm just pointing out that they measure with significantly more variability than better quality caps. A $1 Nichicon 4.7 uF 'crossover' cap purchased at RS had a COV of 8.74%. However, that was an exception to numerous others I tested. It's dissipation factor was also high (>10%) and ESR was 1 ohm. When shopping for caps, you should look for DF"s of 5% or less.
              Keep in mind many hundreds of thousands of commercial speakers have been sold with NPE"s in the HF path and they sounded fine for many years. I'm sure there are those who post here who still support the use of NPE's in the high-pass section.
              Last edited by carlspeak; 04-11-2011, 11:22 AM.
              Live in Southern N.E.? check out the CT Audio Society web site.

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              • Re: Burning in hi-pass capacitors

                Originally posted by jcandy View Post
                ...... I have a sample "8.2 uF Gen 1 Sonicap" that is a nearly perfect 8.05 uF capacitor, not a nearly perfect 8.2 uF capacitor.
                What you've brought up is the age-old QC concept of precision vs accuracy. http://www.google.com/imgres?imgurl=...ed=0CCYQ9QEwAw

                I think your observation is going to be a given, even with the most boutique caps.
                Last edited by carlspeak; 04-11-2011, 11:25 AM.
                Live in Southern N.E.? check out the CT Audio Society web site.

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                • Re: Burning in hi-pass capacitors

                  Burn-in has begun.....

                  Half of the brand new caps are hooked up with a 1h40m program of repeating signals (sweeps, white and pink noise, nature sounds, etc) + a variety of multi-genre music. Caps are wired in parallel. I measured the resistance at the amp speaker binding posts @ 20ohms, so the load on the amp shouldn't be a factor. Volume is moderate. I tested via phones and via a test speaker to make sure the program was indeed running, and all seems to be in order. I plan to let this run till Saturday as long as I don't experience a meltdown before then. :eek:

                  Started the burn-in program today at 10:30am CDT, so I should have 125+ hours of burn-in on these caps if I conduct the listening tests on Saturday night.



                  Bryan K.

                  Midwest Audio Club

                  Speedster | | The Wildeman | Sean's NLA Towers | , COUGAR II and | Triton | Lithium | J-Boom | Trym MLTL | Docere MLTL

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                  • Re: Burning in hi-pass capacitors

                    How were you able to post those giant pictures without exceeding the size limitation????
                    Live in Southern N.E.? check out the CT Audio Society web site.

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                    • Re: Burning in hi-pass capacitors

                      He used photobucket. Imageshack.us works well too and isn't limited either.
                      "He who fights with monsters should look to it that he himself does not become a monster. And when you gaze long into an abyss the abyss also gazes into you." Friedrich Nietzsche

                      http://www.diy-ny.com/

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                      • Re: Burning in hi-pass capacitors

                        Originally posted by Face View Post
                        He used photobucket. Imageshack.us works well too and isn't limited either.
                        Okay, thanks, but how does one use these sites? Once I find out, I'll replace those lame thumbnails in my earlier post with something readable.
                        Live in Southern N.E.? check out the CT Audio Society web site.

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                        • Re: Burning in hi-pass capacitors

                          Originally posted by carlspeak View Post
                          Okay, thanks, but how does one use these sites? Once I find out, I'll replace those lame thumbnails in my earlier post with something readable.
                          Just register and upload your pics on one of the photo hosting sites. Then you copy the embedded html code (the photo site provides the link) into your post by clicking the "Insert Image" button, and pasting the URL to your picture.

                          When you submit your post, the pictures will show up embedded in your post, and NOT as attachments.
                          Bryan K.

                          Midwest Audio Club

                          Speedster | | The Wildeman | Sean's NLA Towers | , COUGAR II and | Triton | Lithium | J-Boom | Trym MLTL | Docere MLTL

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                          • Re: Burning in hi-pass capacitors

                            I have a flickr account. I'll try that first. Thanks for the info.!
                            Live in Southern N.E.? check out the CT Audio Society web site.

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                            • Re: Burning in hi-pass capacitors

                              Flickr is pretty limited unless you are willing to pay FWIW. Still, it will handle like 100 photos if I remember correctly and it has easy editing software.

                              Dan
                              "guitar polygamy is a satisfying and socially acceptable alternative lifestyle."~Tony Woolley
                              http://dtmblabber.blogspot.com/
                              http://soundcloud.com/dantheman-10

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                              • Re: Burning in hi-pass capacitors

                                Originally posted by bkeane1259 View Post
                                Just register and upload your pics on one of the photo hosting sites. Then you copy the embedded html code (the photo site provides the link) into your post by clicking the "Insert Image" button, and pasting the URL to your picture.

                                When you submit your post, the pictures will show up embedded in your post, and NOT as attachments.
                                Can't find an 'insert image' button. I found a 'manage attachments' button. When I paste in the flickr URL it doesn't recognize it.
                                Live in Southern N.E.? check out the CT Audio Society web site.

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