Go ahead, I won't shed a tear, but I suspect you won't. The opportunity of self promoting is certainly worth taking some verbal abuse.
Silver mica is one of the worst capacitors regarding DA. But it is appreciated by audiophiles. How is it possible? 🙂
Because they are very expensive, so they must be good. I think oil/paper is worse and they have a fan club. Let us not forget beeswax/paper/foil, someone actually went back into production making them.
I have an oil cap charging, I want to see how much voltage returns after discharge, then I can estimate the equivalent DA capacitance. (If it returns to 50% of charge voltage then the DA capacitor is equal to the base value!)
Of course there is taste involved. I was impressed by the fellow who ranked carbon composition resistors from his most to least favorites. He got the order to match the distortion measurements exactly. He even noted which two seemed almost identical. Of course his ranking was from most distortion to least.
(Just ran DA test 50 uF rated cap charged to 54.4 volts DC, shorted it and it returned to 9.34 volts! So model 17 uF as the DA capacitor model value.)
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I have a friend whose grandfather chose oil caps based on the loudness of the discharge spark when shorted, the loudest sounded best (lowest ESR?).
But you have to trust your eyes!
This is, IMO, the best version ever:
https://www.youtube.com/watch?v=FFq-fn-nSZI
So how does DA cause distortion, if indeed it is a cause.
Mr RNMarsh (also JC,SW, Bateman and others) has done measurements and come up with the postulation that DA is one cause of throughput distortion in capacitors of various dielectrics.
The notion that a capacitor can be briefly dead shorted, and then delayed wrt the initial short circuit event return a positive, albeit high impedance voltage/energy output implies some kind of return energy slew rate function/limitation.
This effectively very slow slew rate function could cause subtle level shifting of DC operating points in the presence of asymmetric signals....IOW audio signal and not sine test tone signals.
Dan.
Mr RNMarsh (also JC,SW, Bateman and others) has done measurements and come up with the postulation that DA is one cause of throughput distortion in capacitors of various dielectrics.
The notion that a capacitor can be briefly dead shorted, and then delayed wrt the initial short circuit event return a positive, albeit high impedance voltage/energy output implies some kind of return energy slew rate function/limitation.
This effectively very slow slew rate function could cause subtle level shifting of DC operating points in the presence of asymmetric signals....IOW audio signal and not sine test tone signals.
Dan.
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Now who can argue with that? I think we're all indebted to Max Headroom for clearly stating what needed to be said. I'm particularly glad that these lovely children were here today to hear that speech. Not only was it authentic outback gibberish, it expressed a courage little seen in this day and age.
Really? I have not seen any proof that DA is the distortion mechanism. I have also made a lot of capacitor measurements, but would not say distortion was a result of DA.
DA makes longterm time domain errors, in frequency domain errors at very low frequencies, most probably linear errors rather than non-linear distortion.
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