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Crossover A Klipschorn cap replacement help


Aoran994

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People may not be getting physically hurt, but in the audiophile world I do think there should be a little better consumer protection to not get financially hurt. Of course nobody is holding a gun to anyone's head to purchase anything but the sales literature I feel on many things is false advertising.

 

Take a pharmaceutical company selling a pill for say flu treatment but it's only a sugar pill. There would be reviews of people claiming the pills worked and made them feel better from placebo effect. Then whatever agency finds out that the pills are a scam and they are just sugar pills. The company could claim nobody was hurt and people actually benefited from the placebo effect. Morally these companies are not supposed to conduct themselves in this way and there should be consequences. There is a certain amount of trust.

 

Taking advantage of human behavior is wrong no matter what the industry in my opinion. If you spent your life educating yourself in a field and you use your knowledge to dupe people for profit  then that's wrong.

 

People read the sales literature and they make it very convincing due to the technical language and regular people that aren't engineers aren't going to know what they are talking about but it sure sounds legit. I'm not saying the theory isn't correct and with capacitors that have very high dielectric absorption there could be a benefit but I'm sorry, for someone to claim that it makes a "huge difference" with a capacitor that has a DA of .01% then I say that's rubbish. When we are talking about changing something that's -140db or lower it's just not going to make a lick of audible difference due to the transducers always being the weak link in the chain. We are all limited by our speakers, transducers are the weak link in the chain because driver distortion is always going to be far higher than the distortion in the electronics. Tube amps can sound excellent and they are known to have higher distortion than their SS counterparts. Tube amp people will argue distortion isn't everything in regard to sound quality in these situations  so then why waste time with trying to improve a capacitor that is showing no distortion down to -140db? Especially when their SET amplifier is producing 5% THD at 2 watts do they really believe they are going to hear a change of .00001%?   Essentially you are saying you can hear the difference between 5% THD and 5.00001% THD. See how silly that is?

 

Since they have given us the mechanism, and it's well understood. The DA can cause distortions of the waveform around the zero crossing so then it should be easily measurable. The problem is that with a cap that has a DA of .01% most of us can't measure distortion down that far, let alone hear it. Especially when the transducer is giving us 1% THD and that's being fair. We call that a problem we don't need to worry about, there are bigger fish to fry in the signal chain.

 

https://www.syclotron.com/capacitor-obsessions-the-zombie-awakes/

 

 

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1 hour ago, captainbeefheart said:

I'm not saying the theory isn't correct and with capacitors that have very high dielectric absorption there could be a benefit but I'm sorry, for someone to claim that it makes a "huge difference" with a capacitor that has a DA of .01% then I say that's rubbish.

 

 

The 'Huge difference' kind of got me too, seems to hurt the credibility of the claim. 

 

So what caps would you use in the 250 TIs? 

 

In the last ten years I have stuck to Clarity Caps and Jantzen Standard Caps.

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8 hours ago, henry4841 said:

 As stated previously technicians repairing audio gear use a film cap from a reliable source they have in stock when they have a need to replace one. Which is very, very rare for a film cap even 50 years old. Electrolytics are the one that deteriorate with time. 

 

 

 

IO just recapped some Fortes and Chorus with Jantzen Standard Z Caps, they sound great. 

 

I want to see the cost of meters come down more so an occasional user can test ESR.  That would be very helpful. 

 

Funny you mention 50 years.  I was restoring some L100 Centuries and Dean had mentioned that the caps in those are very high quality sealed caps that will last 50 years.  I thought ah heck, I don't need to replace these, until I realized the speakers are 50 years old. 

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40 minutes ago, tigerwoodKhorns said:

The 'Huge difference' kind of got me too, seems to hurt the credibility of the claim. 

 

So what caps would you use in the 250 TIs? 

 

In the last ten years I have stuck to Clarity Caps and Jantzen Standard Caps.

 

That's what gets me, they inflate the claims so much that you almost feel you have to be doing this since it makes such a "huge" difference. I have seen the improvement first hand with caps that have terrible DA characteristics but that's pushing the capacitor into an area of operation to see the hysteresis. I.e. lots of signal across the capacitor. This would mean that signals beyond and below the corner frequency would be where the distortion arises. In a balance/crossover network application, the signals below the corner frequency are the ones we are filtering out and away from passing through the driver. So even if this is where we are starting to see some distortion from the capacitor it's kinda moot since these are not really frequencies of interest. The frequencies we want to pass through the driver aren't going to see the capacitor as a high impedance, and so there isn't going to be an appreciable amount of signal across it and therefore no distortion. We heard it from the horses mouth that the selection for capacitors in these networks were made to retain the desired transfer function and that was the primary criteria. I did not hear him mention low distortion as a major design parameter when selecting replacement capacitors for legacy products.

 

As for what caps to use in the JBL 250, I'll be honest I don't have much experience with these speakers other than hearing them a handful of times. That, and I kinda chuckle at the schematic with all their bypass capacitors. For example on the woofer section they use smaller caps to bypass the larger ones but then tie all the grounds together and run them through a resistor back to the source. Why would you give the high frequencies a low impedance path around the larger caps only to impede them with a resistor? I figure the resistor is there to dampen some resonance but if they really wanted to give the high frequencies a low impedance path back to the source why also run them through the resistor? I can't see any reason to having these bypass caps for the mid-frequency or even high frequency drivers, but possibly for the ultra high frequency driver. Personally I wouldn't touch any of the capacitors unless they needed to be replaced and then I would simply stick with the same type of capacitor. It's a more complex network compared to most of our heritage Klipsch networks and so I really couldn't give an excellent analysis without sitting down and working through the entire design with drivers included.

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9 hours ago, henry4841 said:

very rare for a film cap even 50 years old. Electrolytics are the one that deteriorate with time. 

 

I agree with films rarely fail. The metallized types that are self healing repair themselves but the "clearing" action of these failed spots cause a decrease in capacitance value since essentially that small section of dielectric film and plates have been vaporized and surface area has been reduced.

 

Along with Aluminum Electrolytic caps paper in oil types are prone to fail from age due to the paper absorbing moisture. If the PIO construction has an excellent seal then they can last quite a long time but most of the regular molded paper types are junk now.

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32 minutes ago, captainbeefheart said:

 paper in oil types are prone to fail from age due to the paper absorbing moisture.  

PIO's are quite tough  ,heavyweight grade  paper  absorbs moisture  , + 0 chemicals  or acidity ,  then  you have  the military types/glass sealed  ,  100 years durability 

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13 minutes ago, OO1 said:

PIO's are quite tough  , they use a heavyweight grade  paper that absorbs moisture  , + 0 chemicals  or acidity ,  then  you also have some that are military grade being glass sealed  , we're talking 100 years durability 

 

Yes indeed, that's why I said if they are sealed correctly they can last a long time. Unfortunately in many vintage receivers they are not hermetically sealed.

 

I am a big fan of high quality PIO capacitors in certain applications. Lots of industrial equipment still use paper or hybrid paper/film.

 

I was curious to try these in my Heresy Type E's but the price isn't great and I can get Russian military PIO much cheaper from Bulgaria.

 

2uF paper 1kV (2kV peak),  good for high peak current/voltage and pulse applications so they should be excellent for audio.

 

https://www.mouser.com/ProductDetail/Cornell-Dubilier-CDE/SCRN234R-F?qs=9I6i58cghus89mz%2F6eojrA%3D%3D

 

 

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On 12/16/2022 at 3:08 PM, Aoran994 said:

I contacted jem audio and the price are to expensive to ship here in Italy sadly,like crazy expensive 

I know, and that is exactly the reason why I recommended the caps from Mouser for a small handful of dollars. The result will be similarly good.

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14 minutes ago, geoff. said:

…try the polyester caps @KT88 suggests

 

Your tweeters will thank you, your squawkers will stay reserved, and you will be as close as it gets to the way it is supposed to sound without spending a weeks take home pay

 

This is the last missing cap that I use in combination with those 1.5uF and 4.7uF polyester types I posted above a few days ago to reach 13 uF

 

https://www.mouser.de/ProductDetail/KEMET/A50IT4680AA60J?qs=Jv4FAWB%2B0HY9xI8CEcLngw%3D%3D

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On 12/16/2022 at 9:08 AM, Aoran994 said:

  the price are to expensive to ship here in Italy  

 USPS  

First-Class Package International Service™**

First-Class Package International Service™**

Other than rolls: Min. length 6", Min. height 4", Max. length 24", max length, height and depth (thickness) combined 36"
Rolls: Min. Length 4", "Max. length 36". Max length and twice the diameter combined 42"
Value of contents can not exceed $400.00
Select a Delivery Option Expected Delivery Day Retail Click-N-Ship®
Normal Delivery Time Varies by destination $17.40 $17.40

 

 

 

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8 hours ago, OO1 said:

 USPS 

First-Class Package International Service™**

First-Class Package International Service™**

Other than rolls: Min. length 6", Min. height 4", Max. length 24", max length, height and depth (thickness) combined 36"
Rolls: Min. Length 4", "Max. length 36". Max length and twice the diameter combined 42"
Value of contents can not exceed $400.00
Select a Delivery Option Expected Delivery Day Retail Click-N-Ship®
Normal Delivery Time Varies by destination $17.40 $17.40

 

 

 

They told me 100 dollar for the shipping 🥲

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16 hours ago, KT88 said:

 

This is the last missing cap that I use in combination with those 1.5uF and 4.7uF polyester types I posted above a few days ago to reach 13 uF

 

https://www.mouser.de/ProductDetail/KEMET/A50IT4680AA60J?qs=Jv4FAWB%2B0HY9xI8CEcLngw%3D%3D

I've added to the cart 2 6.8 uF, 2 1uF, 2 4.7uF, 2 1.5uf

Am i missing something for the AA CROSSOVER? Thanks man this way is way way cheaper 

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