• http://www.altavistaaudio.com/caps.html

But you know how it is. On one hand, capacitors are just two plates separated by an insulator. On the other hand, there's chemistry and electrostatics involved, and that makes them all imperfect in different ways. Depending on the interactions with other things in the circuit, some imperfections are more damning than others. Your best part really depends on the application.

Really, I like foil in oil, paper or plastic for signal caps, and metalized film for the larger values. But none of these are usually an option for power supply caps. The values just get too large. So that's where the dreaded electrolytics become attractive. Black Gate, Nichicon or Cerafine might be more in line with what you want. Keep those nice foil in oil caps for the signal path.

Then again, if you have the room for them and don't need large capacitance, give 'em a try. Let us know how they sound to you.

I noticed that Michael Elliott mentioned he liked the Continental caps for power supplies, so there's one positive reference. What I was trying to say is that generally, for power supplies, I prefer the added capacitance that electrolytics bring to the table. That's why I mentioned Black Gate, Nichicon and Cerafine. They're all current production, fairly inexpensive and high quality. They're not your average electrolytic, and some compare them to polypropylenes.

On the other hand, for supplies that don't have large current requirements, large values of capacitance aren't required. I've worked on some tube circuits that only really needed 20uF capacitance in the power supply. That's low enough that you can use capacitors other than electrolytics.

Some of these parts are tens, even hundreds of dollars for a single capacitor. So that's something to think about. And if power supply ripple is a problem, you need big values so a ten dollar premium electrolytic might be better than a hundred dollar foil in oil or polypropylene cap. That's the point I wanted to make.

Wayne

Just to give you an idea of the size of the old oil caps here is a pic of a 15 uF cap. These things were most often made to handle over 1,000 volts so they quite large.

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