DavidDru Posted April 8, 2015 Report Share Posted April 8, 2015 Just a heads up guys, I ordered some non-polar Electrolytics 5% and when I got them they were no where near spec. Supposed to be 12uf and they were slightly above 14uf. These were from Erse. The poly film caps I got were spot on. The Erse folks are to get back to me but that has taken several days unfortunately. (harder than hell to find a phone number to call on the web site)Roy had brought this accuracy issue up recently as well so it makes sense to get it out there for all to be aware of. Be careful and test before use.In this case I was combining a couple to get to 24uf and I tested them in parallel and got a reading of 28.3! I then tested the other 2 I had left to use and they were both around 14.1. Link to comment Share on other sites More sharing options...
DavidR Posted April 8, 2015 Report Share Posted April 8, 2015 That's exactly what Roy said he has been seeing and I've also read of similar issues with their NPE caps.You won't find a number or address for Erse. It made me back away from them. Link to comment Share on other sites More sharing options...
owlsplace Posted April 8, 2015 Report Share Posted April 8, 2015 ... In this case I was combining a couple to get to 24uf and I tested them in parallel and got a reading of 28.3! I then tested the other 2 I had left to use and they were both around 14.1.Unless space is a consideration which it doesn't sound like since you are combining two of them why not just use film caps? Personally I would have used two Madisound surplus 10s with a Carli 3.9 ( ... ha, ha, beat you to it, Kent Roger Link to comment Share on other sites More sharing options...
ra.ra Posted April 8, 2015 Report Share Posted April 8, 2015 from the Erse website:You may also contact us by the following: J & C Group, Inc. 6781 Hopkins Road Mentor, OH 44060 (440) 205-9658 sales@erseaudio.com Link to comment Share on other sites More sharing options...
DavidR Posted April 9, 2015 Report Share Posted April 9, 2015 from the Erse website:You may also contact us by the following: J & C Group, Inc. 6781 Hopkins Road Mentor, OH 44060 (440) 205-9658 sales@erseaudio.comI've never run across that. THANKS for posting this. Link to comment Share on other sites More sharing options...
DavidDru Posted April 9, 2015 Author Report Share Posted April 9, 2015 Unless space is a consideration which it doesn't sound like since you are combining two of them why not just use film caps? Personally I would have used two Madisound surplus 10s with a Carli 3.9 ( ... ha, ha, beat you to it, Kent RogerSorry Roger, roy already had the same recommendation to me earlier in some correspondence. A big single 24 (or a Solen 25) looked like it might just fit, but I was trying to keep cost down on the woofer cap on this particular speaker. But, on teh crossover board there are posts that stick up that the cap is soldered to that a new cap pretty much needs to fit between. On an 8uf I had to install it on an angle between the posts to get enough room for the lead. The much smaller electrolytics would easily fit of course. Link to comment Share on other sites More sharing options...
DavidDru Posted April 9, 2015 Author Report Share Posted April 9, 2015 I've never run across that. THANKS for posting this.I found that and that is how I finally got hold of someone there. Barbra I think. They did not reply to my emails. Link to comment Share on other sites More sharing options...
DavidR Posted April 9, 2015 Report Share Posted April 9, 2015 Customer Service can make or break a company. Link to comment Share on other sites More sharing options...
iso Posted April 9, 2015 Report Share Posted April 9, 2015 Just a heads up guys, I ordered some non-polar Electrolytics 5% and when I got them they were no where near spec. Supposed to be 12uf and they were slightly above 14uf. These were from Erse. The poly film caps I got were spot on. The Erse folks are to get back to me but that has taken several days unfortunately. (harder than hell to find a phone number to call on the web site)When I have bought matched Alcaps from Falcon Acoustics couple of times they have sent flyer explaining how caps were matched. In this flyer they do say that bridge measurement has been done with calibrated bridge for accuracy reasons. As far as I understand, hand held LCR meters do measure discharge time of capacitor... does this mean that different leakage current characteristics of capacitor will compromise measuring results. In 1st order crossovers tolerance is not too critical, but when using 3rd or 4th order slopes tight tolerances are needed.Maybe Carl or Roy do have any idea how much capacitance metering method of LCR meter will compromise results, when measuring crossover capacitors. Best RegardsKimmo Link to comment Share on other sites More sharing options...
Carlspeak Posted April 9, 2015 Report Share Posted April 9, 2015 The good news (if there can be such a thing with out of spec. parts) is most folks resort to NPE's when they need a high value cap to save $ and also a NPE in a non-critical part of the XO such as a woofer Zobel or simple 2nd order parallel cap application. IN THAT CASE, IMHO, the meas. value can be 10-20 % from target and it won't significantly affect the voicing. OTOH, a relatively lower value cap, such as in a tweeter circuit, is best when used within its tol. spec. You can always consider the ERSE MET film caps which are relatively inexpensive vs MKP types and actually have ESR's closer to the NPE's ESR one is replacing.Kimmo, metering caps (if I understand your question correctly), won't affect their performance. Typical LCR meters meas. capacitance at 1 kHz. Be aware though that capacitance can vary with frequency in some caps. However, the really good ones I've measured with my WT2 setup stay very stable from 10-20,000 hz. Link to comment Share on other sites More sharing options...
Aadams Posted April 9, 2015 Report Share Posted April 9, 2015 Having a meter saves the trouble of installing out of tolerance capacitors but it doesn't remove the hassle of going back and forth with the supplier. What, if any, capacitor brands have a reputation for build quality that is within stated specifications to keep the hassle factor low. Link to comment Share on other sites More sharing options...
Carlspeak Posted April 9, 2015 Report Share Posted April 9, 2015 I don't have any details on how ERSE makes their NPE's (if at all), but would suspect any high speed cap making machinery would have an in line quick test to validate the uF value is within spec. If not, automatically kick it out into the reject bin. Why ERSE is selling caps that far out of spec. is a mystery. Link to comment Share on other sites More sharing options...
DavidR Posted April 9, 2015 Report Share Posted April 9, 2015 The good news (if there can be such a thing with out of spec. parts) is most folks resort to NPE's when they need a high value cap to save $ and also a NPE in a non-critical part of the XO such as a woofer Zobel or simple 2nd order parallel cap application. IN THAT CASE, IMHO, the meas. value can be 10-20 % from target and it won't significantly affect the voicing. OTOH, a relatively lower value cap, such as in a tweeter circuit, is best when used within its tol. spec. You can always consider the ERSE MET film caps which are relatively inexpensive vs MKP types and actually have ESR's closer to the NPE's ESR one is replacing.Kimmo, metering caps (if I understand your question correctly), won't affect their performance. Typical LCR meters meas. capacitance at 1 kHz. Be aware though that capacitance can vary with frequency in some caps. However, the really good ones I've measured with my WT2 setup stay very stable from 10-20,000 hz.Interesting and useful info Carl. When a tolerance is given on a cap, say 10%, is that not the 'operating/swing' range of the cap thru out the frequency range, or the range its used in? So a 4uF 10% cap could have a swing of 3.6uF - 4.4uF and a 4uF 1% cap could swing from 3.96uF - 4.04uF. Link to comment Share on other sites More sharing options...
Carlspeak Posted April 9, 2015 Report Share Posted April 9, 2015 Interesting and useful info Carl. When a tolerance is given on a cap, say 10%, is that not the 'operating/swing' range of the cap thru out the frequency range? So a 4uF 10% cap could have a swing of 3.6uF - 4.4uF and a 4uF 1% cap could swing from 3.96uF - 4.04uF.I suppose you could consider that as being the case. However, I'm of the opinion that tol. is around the nominal value at the (pretty much st'd) meas. freq. of 1 kHz. Good quality film caps, as I mentioned earlier, are quite stable over the entire audible freq. range, but they don't have to be. What is important is that they are stable in the range of the crossover freq. of interest because that's where they are doing the job you want them to do. Link to comment Share on other sites More sharing options...
DavidR Posted April 9, 2015 Report Share Posted April 9, 2015 Thank you.What are some of those quality film caps? Link to comment Share on other sites More sharing options...
Carlspeak Posted April 9, 2015 Report Share Posted April 9, 2015 Sonicap, Mundorf, Jantzen, Auricap, Clarity Cap and others. Link to comment Share on other sites More sharing options...
DavidDru Posted April 9, 2015 Author Report Share Posted April 9, 2015 Let's not put Erse in the grave yet on this. The poly caps I got are all great and I want to see what they have to say. The only really bad thing going right now is they have nor gotten back to me with an official response. Of course, they should and the fact it is so hard to track them down is not a good thing. Link to comment Share on other sites More sharing options...
DavidR Posted April 9, 2015 Report Share Posted April 9, 2015 David,I called that Ohio number today and got a wonderful customer service rep. J & C Group, Inc. 6781 Hopkins Road Mentor, OH 44060 (440) 205-9658 sales@erseaudio.com Link to comment Share on other sites More sharing options...
RoyC Posted April 10, 2015 Report Share Posted April 10, 2015 Thank you.What are some of those quality film caps?Frankly, I have never found any film crossover cap of any brand to measure "poorly". This includes Erse and Carli mylar caps, and Madisound "surplus" poly caps. Parts Express Daytons are usually spot on (don't waste your money on the 1% variety). It is not common for any of them to even approach the limits of their 5% tolerance specs. This is why it is hard to define "better" film crossover capacitors. Voltage ratings go up with the price, but I have never been convinced sonic characteristics improve.Regarding the npe issue, I found Parts Express and Bennic npe's to measure no better than Erse. I believe Kimmo is suggesting that the measurement method of a basic capacitance meter may provide different (possibly inaccurate?) results for npe vs film caps due to the nature of npe's. I've wondered about this myself.Carl, do you have a basic cap meter with which to compare your WT results? I don't have a functioning WT program at the moment..Roy Link to comment Share on other sites More sharing options...
DavidR Posted April 10, 2015 Report Share Posted April 10, 2015 Frankly, I have never found any film crossover cap of any brand to measure "poorly". This includes Erse and Carli mylar caps, and Madisound "surplus" poly caps. Parts Express Daytons are usually spot on (don't waste your money on the 1% variety). It is not common for any of them to even approach the limits of their 5% tolerance specs. This is why it is hard to define "better" film crossover capacitors. Voltage ratings go up with the price, but I have never been convinced sonic characteristics improve.....................................RoyOut of curiosity I took a look at the cost for those caps I find it hard to believe they sell lots of them. My Daytons were very close to stated value and I am quite happy with the results.Now I'm wondering what type and brand of cap a speaker manufacturer like Wilson would use on one of their $250,000 speakers. Link to comment Share on other sites More sharing options...
ar_pro Posted April 10, 2015 Report Share Posted April 10, 2015 Out of curiosity I took a look at the cost for those caps I find it hard to believe they sell lots of them. My Daytons were very close to stated value and I am quite happy with the results.Now I'm wondering what type and brand of cap a speaker manufacturer like Wilson would use on one of their $250,000 speakers.A good question.Wilson claims a .5% tolerance, and encases their crossovers in epoxy! Link to comment Share on other sites More sharing options...
Carlspeak Posted April 10, 2015 Report Share Posted April 10, 2015 Carl, do you have a basic cap meter with which to compare your WT results? I don't have a functioning WT program at the moment..RoyI have a LCR meter. However, it doesn't meas. ESR. The LCR meter has 2 freq. options, 1 kHz and 120 hz. When meas. caps, I keep it at 1 kHz which is the default freq. when you turn it on. I have compared results and found they correlate nicely. Link to comment Share on other sites More sharing options...
DavidDru Posted April 10, 2015 Author Report Share Posted April 10, 2015 David,I called that Ohio number today and got a wonderful customer service rep. J & C Group, Inc. 6781 Hopkins Road Mentor, OH 44060 (440) 205-9658 sales@erseaudio.comAs did I yesterday. it was day 3 after emailing and not getting a response. She said the guy that would be able to look into this was out until later this week.They need to make a phone number more available to customers that purchase stuff. There isn't even one on the invoice. Also if they want to use email for inquiries, they better answer those promptly. Link to comment Share on other sites More sharing options...
iso Posted April 10, 2015 Report Share Posted April 10, 2015 I believe Kimmo is suggesting that the measurement method of a basic capacitance meter may provide different (possibly inaccurate?) results for npe vs film caps due to the nature of npe's. I've wondered about this myself.RoyThis is what I was suggesting... Electrolytic´s seems to have higher leakage current than film caps. When I have formed some old high voltage electrolytic´s with series resistor and 400V PSU, leakage may have been something like 20+ mA and after 2-3 hours forming leakage may be less than 1 mA. I have experienced similar behavior also when I have charged say 10 old NOS electrolytic´s to rated voltage... when charging first time to rated voltage charge will drop to say 5 volts during 10 hours... when recharged charge will last considerably longer time. Is it possible that this will limit accuracy of LRC meter when measuring NPE´s or other electrolytic´s? I suppose bridge measurement does not have this disadvantage.Best RegardsKimmo Link to comment Share on other sites More sharing options...
Pete B Posted April 15, 2015 Report Share Posted April 15, 2015 Electrolytics are often measured around 100 Hz because their value is somewhat frequency dependent.The tolerance is from the rated value however they are measured not over the frequency range.It would be good Carl to measure a big NPE at both low and mid frequency on your meter. I have somedecent meters but I don't think any of them measure capacitance.I use LAUD to measure capacitors and inductors.Not all DMMs work like this, but it is one reference:http://en-us.fluke.com/training/training-library/test-tools/digital-multimeters/how-to-measure-capacitance-with-a-digital-multimeter.html Link to comment Share on other sites More sharing options...
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