Duelund silver foil capacitor 'autopsy'

I opened a Duelund capacitor, so you don't have to do that :) I thought that Duelund capacitors are physically bigger than Jupiter Silver Foil -Vitamin-Q because they have more foil and are better quality, but I was wrong. I found a ton of epoxy instead. The manufacturer could fit to 15mm diam package as 0.01uF, But for some reason he did't. I wonder what the real size of 0.01uF.. Overall these are great capacitors, I have no complaints about the sound quality


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I'm probably best saying nothing... I'll just think it instead.

Reminds me this picture...
Exactly what I thought although I would hope the actual foil cap is probably OK as it goes.

Specialist audio is to small a business for one off specialist parts to be made (imo). Not enough demand... I'll say no more.

All very interesting.
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Looks very hand made in Denmark. The edges of the foil sticking out could overlap. Strange that it is not trimmed more precisely.
Thats what you call “extended foil construction” - it reduces inductance. the two foils are offset from one another and then the leads are soldered to to all the ‘flappy bits” as opposed to just one point on the foil(s). Not unique to Dueland very common in foil capacitors.
So I did listening comparison between potted and naked foil capacitors. As a coupling capacitors. Naked foil sounded a little more natural, just a hair. The difference was so small that it took a long time to compare. Epoxy really doesn't do anything positive :) Bigger package is just a marketing thing
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