Capacitor upgrade for Quest Z, Recommendations?

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Agosto

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Hi folks, I posted my question already on 1/9, unfortunately without response so I am trying again: I intend to upgrade the crossover capacitors after owning my Quest Z for 25 years. Panels were replaced last year. I was searching this forum for information and found lots of info in particular about "Mundorf" capacitors. As they are out of my price range I was thinking of getting Solen PBs. I understand that they are not as good as Mundorfs but can I expect a decent improvement over my "Richey" capacitors, which most likely are no longer functioning to spec anyway after all these years?
One capacitor rating I need to replace is 470uF, which I intend to reach with 200+150+120. The Solens need a lot of space but I think I can manage.

Any recommendation?
 

ttocs

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I'm not qualified to respond to the quality difference question you pose, but I am curious as to the value/voltage ratings you are in need of?

Also, I'd recommend investigating the audio implication of "stacking" capacitors to reach a calculated value. When I've replaced series capacitors as well as capacitors in parallel in vintage electronics they've always been multiples of the same value, so my question really is pointed at using 3 different values and if this would have any negative impact.
 

JonFo

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I saw the original and did not reply, as I'm all in favor of bypassing the passive crossover and using a modern speaker processor.
But in that case, you replace the need to understand analog electronics, with the need to understand speaker and room acoustics measurement to correctly set the speaker processor. And since that later skill set is universally useful in setting up and optimizing any audio system, it's one I highly recommend learning.

But I perfectly understand that's not everyone cup of tea.
 

Agosto

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ttocs, JonFo thanks for your responses. Stacking: Yes I understand the concern but I can not find a 470uf capacitor in the "audio" category. The rated voltage of the existing Richey electrolytes is 100V but I plan to go with 400V based on recommendations here at the forum. Of course I would prefer to install just one capacitor...Any suggestions?

Speaker processor: This is more than I want to get into at this point so I plan to settle with a capacitor replacement.

Thanks again
 

Tosh

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Is this for the cap in parallel of the woofer in the low pass xo?
Use four 470uF 63V Elna RFS (Silmic II) electrolytics in series-parallel, which will give you a non-polar equivalent of a 470uF 120V cap.
 
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