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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 11 responses by pauly

pauly OP
1,012 posts
 
@oldhvymec

Yep, taller & wider (diameter). I’m sticking to the same value. I’m looking at 47uF/400v. 

Yep, radial, if that means both leads exiting on the same end.  😂🤣


pauly OP
1,012 posts
 
Are you using the Audio Note KAISEI caps? Great caps!


I’m looking into kaisei caps - the value I’ll need to get has snap on connectors -> 50uF/500v. They have a 50uF/350v with leads but I’m uncomfortable going down to 350v given the board specifies 47uF/400. The actual caps are 47uF/450v so …

I was also looking into Mundorf MTubes, but if anything they’ll be more challenging to mount than the kaisei. 
I was also thinking of drilling holes in the PC board that match the cap spacing and the routing the leads to the existing holes underneath the board. I’d need to glue the caps in place with some non conductive epoxy. 
I’ll look into Soundcoat . Never heard of it before.


pauly OP
1,012 posts
 
@grannyring 

Have you used glue on PC boards before? I'm worried an epoxy may be too much and you end up with a hole in the board when you want to change later on. A friend of mine used a glue gun but that is way to much heat for my liking. 
pauly OP
1,012 posts
 
@grannyring 

I’ve taken a peek inside my 2A3 monos, and over there I have all the space in the world for cathode bypass caps. I was wondering if you have tried Solen PB caps for cathode bypass? 
I’m thinking they’re film, which beats an electrolytic all day long, and they’re very inexpensive. Size is not a problem. 
pauly OP
1,012 posts
 
@grannyring

Why not Clarity CSA?

I wasn’t aware of the Clarity caps.


Honestly, after posting I saw VH makes both a 47uF ODAM and 47uF OIMP, so I had been thinking of going for one or the other. The Clarity is about half the price of the VH audio caps, so that’s probably the more sensible choice.




pauly OP
1,012 posts
 
Jeez, the Clarity caps aren't really small are they? Wow. 


pauly OP
1,012 posts
 
@grannyring


I’ve put the Clarity in a cathode bypass position on a driver tube and it sounds very good. It added a ‘gentle’ but detailed quality. Thanks for advice; good call as always!


You mentioned Solens are ok in a power supply. I’d love to use Clarity but they are just too big. Is it worthwhile to swap out the cheap electrolytic with Solens?


Also, would it be worth looking into using large value Solens bypassed by a smaller Clarity - Lets say a 51uf Solen and a 10uF Clarity? I’m talking power supply decoupling caps.


Thanks
pauly OP
1,012 posts
 
@grannyring 

Yep, I keep uF the same (or close) and voltage I'll either go up or at least keep the same. 

Sizewise I cannot swing Clarity or Mundorfs. At a pinch I can squeeze in Solens, but as you mentioned they're not very good. If they aren't an improvement over electrolytics, I won't bother. 







pauly OP
1,012 posts
 
@grannyring 

Thanks, I’ll look into them. I’ll probably go for one of the three prong MLytics. Given the cost of the kaiseis, I’ll use them on cathode bypass positions only. On a power supply the cost would run up pretty fast. 

Reading between the lines, you really don’t like Solens, do you? 😂🤣
pauly OP
1,012 posts
 
Got you. I am interested in using film for both better sound and reliability. I’m going to try and see if I can squeeze Mundorf Tubecaps in. 
The 30uFs are rectangular and if I can superglue them against the sidewall I’ll get them enough of them in. Maybe. 
pauly OP
1,012 posts
 
@grannyring


Ok, short of taking a hacksaw to my chassis, I cannot use Tubecaps. I think I’m going to have to settle the Mundorf Mlytic. Do recommend bypassing them? 

I want to use the 50+50uF three prong. The ODAM is a little too expensive for bypassing - I need to replace 4 caps per amp. I’m a little under spec, the current electrolytic are 56uF. What would you recommend?
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