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Why are my crossovers different

So the schematic on my m1 crossovers says that c2 circuit (midrange circuit) should total 26.7uF
The crossover that I just recapped had the c2 circuit at 25.7uF.
The crossover I’m working on right now has the c2 circcuit at 28.1.
It does not appear these have not been tampered with since the factory.
So the question is should I make the second c2 circuit match the 25.7 of the first or should I put it back the way it was at 28.1

I could make the second one a 26. 8uF. I accidentally damaged a 1.3uF that was in the 28.1. So I’m debating on whether I should replace it or leave it out.

Your input would be appreciated
idahifi
idahifi OP
100 posts
 
Update

So measured the old caps.

In speaker A, the midrange circuit measures 24.7
In speaker B, the midrange circuit measures 26.3
It's a 1.3 uF  difference. 

Speaker A midrange circuit has been replaced with 25.7

Now I'm trying to determine  whether I should put speaker B the same as speaker A (25.7) or back to where it was at (26.3) or 26.7 which is what the schematic calls for. 
Your thoughts 

idahifi OP
100 posts
 
Not sure it makes a difference  but speaker A is actually 25uF, not 24.7
idahifi OP
100 posts
 
On speaker B I could use 2, 10uF and a 6.8, or
2, 10uF a 4.7 and a 1.5.

Is there a benefit to using the 4.7 and the 1.5 over using the 6.8
erik_squires
5,268 posts
 
There is a small amount of series inductance that is proportional to the capacitance. The smaller the cap, the smaller the unintended inductance.

Modern caps have gotten a lot better at reducing inherent inductance, so this is less of an issue than it was before. Chances are good this no longer matters.

But, given a choice of all things being equal, choose the combination with the smallest cap.

However, that's from the design perspective. What you really should do is match both sides identically to ensure they have the same characteristics of capacitance as well as inductance and equivalent series resistance.


Best,

E
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