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Electrolytic capacitor replacement

I want to swap out a couple of electrolytic caps with higher quality caps, also electrolytic. The ones I am looking at are all physically bigger than the ones I am replacing, and consequently the leads don’t fit the board. The rubicon’s I want to bin are have a diameter of around 3/4’ and the caps I’m considering are between 1’ and 2’. The big issue I have is the lead spacing.

I’m considering using a spacer between the pc board and the cap giving enough room for the leads to bend enough to fit the board. I have space on the board to fit a larger cap, but not enough to mount the caps on their side. The caps new will need to sit “upright”.

Id appreciate it if somebody has figured an eloquent solution for this.

Thanks
pauly

Showing 2 responses by itsjustme

itsjustme
681 posts
 
Elegant would be more eloquent. Ditch the board. Hardwire direct. That's what I did. See the last couple pics on my system page.

:-) correct on both.  But wait, there's more.
I often drill holes in the existing PCB that match the leads, and use copper solid wire to hard wire it.  use adhesive ot hold the cap firmly in place.

Now, in what what are the new one's "superior".  If not larger, you are barking up the wrong tree. On a relative basis 'lytics suck -- all of them. Use the world's cheapest film cap in parallel and it will still b 10X better.  I suspect one is already there. if not shame on them.  I means really shame on them.
itsjustme
681 posts
 
I ought to have added, what i define as "superior" are the characteristics that affect sound quality, specifically both frequency and phase linearity. They are dissipation factor and dialectic absorption. Both are often on the datasheet. ’Lyics range from bad to worse. Films range from good to excellent, and are way more stable. But they are vastly less size efficient (small values in big packages) and so are only usefully applied in parallel to handle the frequencies that are most affected.
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