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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

Showing 15 responses by idahifi

idahifi OP
100 posts
 
So the allowable tolerance is 2%. I was just going on what was printed on the caps 
idahifi OP
100 posts
 
Maybe the caps the factory used ware not accurately labelled. Question is, how accurate are the labels on the jantzen standard z caps 
idahifi OP
100 posts
 
It's strange  because on the first crossover there is a 10uF, another 10uF, a 4.7uF and a 1uF, making 25.7

The second crossover it had a 10uF another 10uF, a 6.8uF and a 1uF making 27.8
These are only what is printed on the caps. 
Again the schematic calls for 26.7
 
I'm thinking they likely measured each cap to make the 26.7
idahifi OP
100 posts
 
I think I'll just mirror the other crossover, any thoughts on this 
idahifi OP
100 posts
 
Also on the 25.7 crossover the 1uF cap it said 1.0m100v,  I assumed this meant 1uF.
 On the other crossover the 1uF cap had the stripes, I punched in the stripe code online and it said it was 1.3uF-1.6uF at 100v

idahifi OP
100 posts
 
I've heard these older pairs were hand built, so I guess it makes sense the midrange  circuit of each speaker could be slightly different from each other. 
idahifi OP
100 posts
 
I think i will buy  the meter and test the old caps, excerpt for the broken one and see if there all as labelled,  then I can get an idea where it was set at. Maybe the factory had this one a pinch above the spec 
idahifi OP
100 posts
 
So going back-to what GS5556 said is it probable that Mirage Deviated from what the schematic said of 26.7 depending on what the drivers read. This would mean that each speakers crossover May have a different value depending on The drivers that it had.So for instance The mid range circuit in one speaker might have a total capacity its of 27.5 and the mid range circuit in a different speaker would have maybe 25 asper how they matched it to the individual drivers in the cabinet 26 being the baseline but the factory would deviate as-needed. is this likely 
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 
idahifi OP
100 posts
 
Stupid question, but can you do that on the board are no. I realize that it's the bundle that has be measured I just thought I would just add the values 

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
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