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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
erik_squires
5,268 posts
 
You can use Room EQ Wizard, or DATS to measure your caps with high accuracy and the correct ESR.

https://www.roomeqwizard.com/help/help_en-GB/html/impedancemeasurement.html

https://www.parts-express.com/dayton-audio-dats-v2-computer-based-audio-component-test-system--390-8...

Also some handheld meters I know nothing about.

Best,

E
gs5556
769 posts
 
Ditto on measuring. I would take the group of 4 caps you removed from each board and measure their capacitance in parallel and that is the value I would use for the new ones.

The design value may 26.7 but chances are the manufacturer tested every driver and tweaked the caps to allow for variations in driver paramenters to meet overall design specs. (If one of the four caps is much smaller in physical dimension than the others, then that is almost certain what they did).

Without measuring the original caps, your best bet is to install 26.7uF total.
idahifi OP
100 posts
 
I looked at my buddy's pair and his are 26.3, two 10uf,  a 4.7 and a 1.5.
Here's the question... can they be measured on the board. I have taken this crossover apart a million times and I'm not going to desolder  the finished crossover to measure each cap. 
So the question is do I put it back at what was original with the 28uf,  or do I get it close to the other side 25.7.

Or just get it as close to the 26.7, which if I leave the 6.8 in there and leave the 1uf out. I'd have 26.8 

idahifi OP
100 posts
 
Here's something kinda interesting,  the 4.7 on my buddy's pair look identical in shape and color to the 6.8 that's in place of the 4.7 on mine.  It sounds stupid but I'm wondering if the gut putting it together thought it was a 4.7 but it was actually  a 6.8
idahifi OP
100 posts
 
Also I can't measure all the original caps because the last one broke, it was damaged when I removed it.  It was the one with the stripes which came out as 1.5uF  I think 
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