Yup; done this sort of thing often, most recently in a pair of Audio Physic Avanti IIIs. In those, the 2 caps in series with the tweeter were a 6.8uF and a 15uF. I replaced both with the highest-quality-composite cap I chose to afford, and this time I wasn't cheap. Altho the highest-value SoniCap Platinum (Teflon-film) cap Sonic Craft lists on the site is a 4uF, Glowacki had a pair of preproduction 6.8s, so I bought and installed them, and the 15uF turned into a 12uF SoniCap Gen.1 'propylene plus a 3uF Platinum. (Claity Caps were original.) Altho I'm no golden-eared audiofile the way some of my friends are, I heard MUCH-cleaner and less-edgy treble, so much so that I was able to increase the average level of listenable treble several dB. I suggest a combination such as I used or perhaps with as high a value of MultiCap RTX you choose to afford with a SoniCap Gen.1 to fill the value to the original.
What is/are the value(s) of the tweeter cap(s)?
BTW, then it's the midrange's turn. :-)
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Bryon, you need to remove the board and trace the schematic, at least for all devices connected in any way to the tweeter outputs. Then you'll know if you have a 1st-, 2nd-, or 3rd-order filter and if there are any resistors in the circuit, etc. I too would replace the resistors in the tweeter and MR circuits but would not replace the inductors, as they 'sound' the least compared with caps and resistors. For the latter, use Mills Wire-wound noninductive 12-Watt resistors; they're VERY reliable and sound quite good.
Do this in stages, Bryon, and help us help you to do it correctly.
I too would NOT use Solens except to replace 'lytics in the bass section.
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...and trace the MR section(s) too. Caps and resistors in series with that driver(s) definitely add bad stuff to and subtract good stuff from the music.
BTW what do you think your speakers are worth, generally?
Just tonite I finished the covers for the Avanti outboarded crossover boards.
http://i89.photobucket.com/albums/k220/jeffreybehr/Avanti%20IIIs/Overallfroml-rear_1280w.jpg
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Bryon, help us help you by tracing a schematic diagram of all sections of the x-over. It's really easy to tell you to replace all the film caps with other expensive film caps, but that does no one except the cap seller any good. If you think that's beyond your capability, get someone else to do it. I find it easier to start with the output sections, not the inputs. Since the output wires are clearly labeled, you have a head-start on the project.
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J indicates value tolerance; I don't know what exactly 'J' means, but I"m sure someone does.
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Bryon--of course you're free to take this advice--or not--as you wish, but--
1. Stay away from Clarity Caps. That's what I removed from my Avanti tweeter filters. 'Clarity' my a...er...eye. I've been playing with caps for about 40 years. The SoniCap Gen.1 is the overall-best-sounding affordable cap there is.
2. Build the correct values with 2 caps. I believe you'll be thrilled with the results of using SoniCap Gen.1s paralleled with MultiCap RTXs, or, if you choose to afford them, SoniCap Platinums. The higher proportion of higher-quality cap, the cleaner/quicker/smoother the sound will be; I learned that dramatically in my TWO upgrades of tweeter caps.
3. Piggyback the 2 caps. If the larger of the 2 caps won't fit on the board, put the smaller on the board with the larger above it. I use 3M double-side self-adhesive foam tape. That plus the leads will hold the caps in place forever.
4. Replace the resistors in series with Mills MRA-12s, noninductive wirewounds.
5. Unless it takes hours to get to the x-over boards, do your upgrades in stages, with the tweeter section first.
The new caps in my x-overs made the treble so much better sounding that I now listen at around 5dB higher treble levels. You can tweek your treble balance by changing the value of R1.
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Byron, the approximate voltage-rating minimum for x-over caps is about FIFTY. 250VDC caps are used by manufacturers because they're available. 100s and 200s will work perfectly.
One can always use higher-power-rated resistors to replace lower-rated ones.
In paralleling caps, one uses the SoniCap Gen.1 for most of the value and the RTX or Platinum as the 'filler'. The higher proportion of higher-quality cap, the better-overall the sound is. And remember, ending up within c. 5% of the rated values is JUST FINE.
You're making this project WAY too difficult. :-)
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I too wouldn't mix brands of caps between the 2 positions, and I wouldn't use Clarity caps if they were free.
Mundorf SOs are fine. If the caps are too large in diameter to reach the board, use a half-inch-square chunk of wood on the board as a spacer, cap on the wood, 3M foam tape holding all layers together, and a plastic ziptie thru the board.
But I'd still use SoniCap G1s and Platinums. :-)
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E-mail Jeffrey Glowacki of Sonic Craft for advice. He knows more about crossover parts than ALL of us put together.
mail@soniccraft.com
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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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Voltage is as much a determinant of size as is capacitance. Also, film caps occupy lots more volume per Farad than 'lytics.
Just make sure you read them carefully. 56uF is not unusual in a MR filter; mine had a 33uF 'lytic.
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