Help crossover Boston A20

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Hi,

I bought this Bostons A20 and the sound pretty good, but i want them to upgrade the caps...as the speakers looks like they are from the 80 i think (couldnt find any info online)

Im not really sure what to get, Any recomendations for caps? They are betwen 20-100 mfd bipolar 50 vw

Would make any difference to get a more high end cap for this crossover/speaker?

Cheers!
 

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If you want inexpensive, smooth, dark, Mundorf MKPs are something you can try. Let them break in for 2-4 days of playing.



Clarity CSA after that.



I would do them in ascending order. That usually means, the tweeter, then the mid, and finally anything on the woofer portion.



Keep your prices small, and treat this like a learning experience and this way you'll have fun and start to figure out what you are doing.



You may want to get XSim to help you draw out your crossover before you begin.


Best,


E
 
A picture is worth 1000 words.
Look again.
I believe the 2 left most caps, and the 1 right most cap are Bipolar.
I believe the 2 middle caps are Not Bipolar.

But I do notice another possible issue.
The largest inductor has an Iron or Steel Core.
I would consider replacing it with an Air Core inductor (it will be Much larger, and will need to have Much larger wire). That way you can get the same inductance, and the same DCR.

I am not opposed to keeping the original inductor . . .
But I would like some others to give there comments about non-air core inductors.
They are generally for woofers, and so they have the largest signal currents.
I think the only thing that reduces the harmonic distortion of non-air core inductors is the low pass capacitor that is connected across the woofer (but the attenuation of those harmonics is not a sharp cut off).
 
A picture is worth 1000 words.
Look again.
I believe the 2 left most caps, and the 1 right most cap are Bipolar.
I believe the 2 middle caps are Not Bipolar.

But I do notice another possible issue.
The largest inductor has an Iron or Steel Core.
I would consider replacing it with an Air Core inductor (it will be Much larger, and will need to have Much larger wire). That way you can get the same inductance, and the same DCR.

I am not opposed to keeping the original inductor . . .
But I would like some others to give their comments about non-air core inductors.
They are generally for woofers, and so they have the largest signal currents.
I think the only thing that reduces the harmonic distortion of non-air core inductors is the low pass capacitor that is connected across the woofer (but the attenuation of those harmonics is not a sharp cut off).
 
I believe the 2 left most caps, and the 1 right most cap are Bipolar.
I believe the 2 middle caps are Not Bipolar.
I think you mean that the 2 left most caps, and the 1 right hand cap appear to be NP electrolytic types.

The 2 middle caps would appear to be NP film types.

Normally, it is only worth changing old, out of spec, electrolytic capacitors for new ones. Film caps do not age and can be left alone.

P.S. The steel or ferrite cored inductor is OK for low bass duties where a small amount of distortion is tolerable.
 
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