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If it quacks like a duck…

Sal1950

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I don't know their history well enough to comment or vote. Is John Curl really one of the "measurements only go so far" folks? And was McGowan ever not?
I don't have the tech chops to comment on much of Curls ideas on capacitors and such but he is probably right the the best cap is no cap whenever possible?
As to Paul, there was a time going back to the 80s when PS Audio specialized in bringing the best possible sound at a very low cost to the market.
I owned the PS III phono stage for many years that gave excellent results with both high end MC and MM needles.
Then he caught on that there was a LOT of money to be made with very expensive products and pseudo-science claims. The rest is history.
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mansr

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I don't have the tech chops to comment on much of Curls ideas on capacitors and such but he is probably right the the best cap is no cap whenever possible?
I'm not familiar with with Curl's ideas, so I can't comment on them directly. That said, in a settled branch of engineering, such as audio amplifiers, when someone has unorthodox ideas, they are usually bad ideas. Sometimes a little digging will reveal them to be a resurrection, intentional or accidental, of a design long abandoned for good reason.

As for capacitors, the best choice depends on the purpose of the component. If we're talking about power supply filtering, any capacitor is better than no capacitor. I'm guessing the statement you're referencing was in regard to DC blocking on the input or output of an amp. This has to be done somehow, and a capacitor is one way. Other methods have their own advantages and drawbacks. "Capacitors bad" is an overly simplistic view.
 

SIY

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I don't have the tech chops to comment on much of Curls ideas on capacitors and such but he is probably right the the best cap is no cap whenever possible?

I do and I have. Another one of those "there's a germ of truth, but it's been completely blown up into something it's not" deals. Curl took the correct idea that some dielectric types have higher DA (dielectric absorption) than others into the notion that this somehow makes low DA caps better for coupling. This is what started out the cap rolling craze. DA is important in timing circuits. It is absolutely irrelevant to coupling caps, and I've posted measurements to prove it.

For caps used in filters, there can be some small measured differences between dielectric types, but once a certain point is reached, it's not terribly relevant. For example, polypropylene (cheap) will measure better than polyester and is preferable. Polystyrene (more expensive) is slightly better, Teflon (extremely expensive) slightly better yet. But PS and Teflon both have major disadvantages which don't get considered by the cap crowd, and of course, polypropylene already gets you to the point where the distortion is beyond negligible.

Of course, all of this is dismissed because "everyone knows Teflon sounds better" or somesuch. Here's a list of actual controlled listening tests supporting these claims:








Oops.
 

Sal1950

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As for capacitors, the best choice depends on the purpose of the component. If we're talking about power supply filtering, any capacitor is better than no capacitor. I'm guessing the statement you're referencing was in regard to DC blocking on the input or output of an amp.
Yes that was it. In conventional power supplies, the bigger the better is usually the case. ;)

Of course, all of this is dismissed because "everyone knows Teflon sounds better" or somesuch. Here's a list of actual controlled listening tests supporting these claims:
I've heard oil caps sound the smoothest. :)
 

Hipper

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If it quacks like a duck..... it could be a magpie!

A story on the radio reported that there was a house with a pet magpie in a cage in a living room with a cat. The living room opened to a large garden and quite often ducks would waddle across the lawn. If the cat saw this it ran out to chase them off. One day apparently the magpie mimicked the ducks quaking sound and the cat steamed out to do his duty but was puzzled that no ducks were about.
 

graz_lag

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If it looks like a duck, walks like a duck and it quacks like a duck then it's a duck.

I read it some time around Nov-2016 but do not remember to whom it was referring ... ;)
 
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