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Speaker crossover mod. Your advice?

I'm considering modding the crossovers of my Focal 1027s. Specifically, I am thinking about replacing the capacitor associated with the tweeter. I have received some helpful advice from another A'gon member who has done a similar mod to his crossovers (on a different model speaker from the same manufacturer).

I would greatly appreciate any suggestions from folks who have experience with this sort of thing. In particular, what sort of improvements can be achieved with this kind of mod? Any thoughts on which caps to use? Any common mistakes I should avoid? Is the whole thing a bad idea?

Thanks for your input.

Bryon
bryoncunningham
bryoncunningham OP
888 posts
 
Just spoke with Jeff from Sonic Craft. Very knowledgable and very helpful. Here is what he recommended:

1. Tweeter cap C1. Replace with (2) Mundorf s/o in parallel (1.8uF + 1.8uF)

2. Tweeter cap C2. Replace with (1) Mundorf s/o.

3. Tweeter Resistor R1. Replace with Mills MRA-12.

4. Midrange cap C3. Replace with Jupiter Vintage Flatstack + Black Gate AC series in parallel (exact values TBD).

5. Midrange caps C4 & C5. Replace with Sonicaps Gen 1.

6. Bass caps C6 & C7. Replace with Axon or Solen caps.
magfan
1,583 posts
 
NO inductor change recommendations? hmmmmmmm.
bryoncunningham OP
888 posts
 
Correct.
jeffreybehr's avatar
jeffreybehr
805 posts
 
Magfan, of the 3 types of passive components in hi-cuurrent filters, coils have the least sound. Also, their resistance helps determine the Q of the filters. So one could spend a lot of money and time buying new coils with matching inductance and resistance and produce NO audible difference in sonic quality. 'Tis much better to spend that money on higher-quality caps.

He gave me the same advice (but for specifics on tweeter caps) on the filters in my Avanti x-overs, I heeded it, and I'm thrilled with the results.

Bryon, I believe you'll be very happy with your results.
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bryoncunningham OP
888 posts
 
I have one lingering question regarding the values of the caps for the midrange. Here is how they are labelled on the caps themselves:

MIDRANGE CAPS
C3 = 56µF 63V, bottom right of this pic
C4 = 12µF 63V, bottom left of this pic
C5 = 4.7J 250V, top left of this pic

Notice that C3 and C4 are both SMALLER than C5, yet according to their labels, they are much LARGER values.

I am now wondering if C3, which is marked 56uF, is really a 5.6uF cap. Likewise, I am wondering if C4, which is marked 12uF, is really a 1.2uF cap.

Could C3 and C4 really be 56uF and 12uF and still be much smaller than C5 which is 4.7uF? Or can I infer from their small size that they are really 5.6uF and 1.2uF, even though there are no decimal points on the caps' labels?

I just don't want to order the wrong midrange parts.

Bryon
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