Polyester OK for a PS smoothing cap?

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I've got an unregulated PS for a class A amplifier with a 60,000uF CRC filter. I want to put some local filtering on the left and right channel boards, and was thinking an electrolytic + a film.

I've read all about the evils of polyester films, but I assume that's for signal path stuff, not for this application. But folks get religious about this, so I'm not sure.

How would you rank the following:

a) just a 470uF electrolytic
b) a 470uF electrolytic + 6.8uF polyester (Wima MKS40)
c) a 470uF electrolytic + 0.1uF polypropylene (Wima MKP)

Thanks,
Jeff.
 
It's sort of a cross between Pass's ZV9 and his F3. Here's the ZV9 schematic (C2 and C6 are the ones in question):

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C6 is spec'd as 10uF. A polypropylene that size won't fit on my board. (C2 got bumped from 220uF to 470uF just because I have some of those already.)

Note that in the F3 Nelson deleted C6 entirely. Thus my option (a) if a 0.1uF cap really isn't going to do much, and polyester is out.

Thanks,
Jeff.
 
Sorry, should have been more specific, meant that the polyester, with its higher esr, is less likely to ring than the polypropylene part in most situations.
Location/distance is a big factor too I have noticed, the inductance of the leads or traces can wreak havoc with certain part combinations.
The slightly higher esr parts seem to work better on power rails.
 
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