I should add, impedance measurement tools are vastly under appreciated as diagnostic tools. Being able to measure the impedance of your entire speaker before and after mods is gold. I like DATS but you can do it with REW and a jig, and there's another popular device I forgot the brand.
Thanks, @eriksquires
You may have noticed, I have little to no knowledge in crossovers (ref - me speaking of going for caps in series instead of parallel 🙂 ). But it would be interested to learn and upgrade this crossover (may be with the assistance of a professional - but I want to know what is going on). Saying that, I may not go into the route of multiple tests of tries and errors.
So, it is meant to be an upgrade to an already not-that-cheap speaker, I will not be doing it for budget reasons, however not going insane on exotic caps.
Measurements are unlikely to happen, so no credible way to know how to correct potential cap ESR issue with adding a series resistor to compensate.
On the 120/150 uF electrolytics - I may go for film caps (that will be $40-50 per cap for basic Jantzen CrossCap MKP, not terrible, but these are like soda cans, space my be another issue), but if that will cause unpredictable impendence deviations, not worth it.
What is your take on bypassing electrolytic cap with film cap of about 10% (like the KEF R series approach discussed here: https://www.diyaudio.com/community/...acitors-for-crossover-use.365874/post-6487040). Then the problem is getting that ~10% right. I may be wrong, but Mundorf RAW 56+47 poly bypassed by an 18uF film may not be the best idea.
For the 3.9 uF at twitter I will probably go for Jantzen Silver Z / Mundofr MCap Supreme Oil.
I was advised that the parallel components at mids and twitter are not that important for sound, so may remain as is (still may change the 8,2 uF cap at mids for a e.g. Jantzen Silver Z / Mundofr MCap Supreme Oil, but the iron core coil may stay. The two series coils at bass and mids are to be changed with air coils.
You may have noticed, I have little to no knowledge in crossovers (ref - me speaking of going for caps in series instead of parallel 🙂 ). But it would be interested to learn and upgrade this crossover (may be with the assistance of a professional - but I want to know what is going on). Saying that, I may not go into the route of multiple tests of tries and errors.
So, it is meant to be an upgrade to an already not-that-cheap speaker, I will not be doing it for budget reasons, however not going insane on exotic caps.
Measurements are unlikely to happen, so no credible way to know how to correct potential cap ESR issue with adding a series resistor to compensate.
On the 120/150 uF electrolytics - I may go for film caps (that will be $40-50 per cap for basic Jantzen CrossCap MKP, not terrible, but these are like soda cans, space my be another issue), but if that will cause unpredictable impendence deviations, not worth it.
What is your take on bypassing electrolytic cap with film cap of about 10% (like the KEF R series approach discussed here: https://www.diyaudio.com/community/...acitors-for-crossover-use.365874/post-6487040). Then the problem is getting that ~10% right. I may be wrong, but Mundorf RAW 56+47 poly bypassed by an 18uF film may not be the best idea.
For the 3.9 uF at twitter I will probably go for Jantzen Silver Z / Mundofr MCap Supreme Oil.
I was advised that the parallel components at mids and twitter are not that important for sound, so may remain as is (still may change the 8,2 uF cap at mids for a e.g. Jantzen Silver Z / Mundofr MCap Supreme Oil, but the iron core coil may stay. The two series coils at bass and mids are to be changed with air coils.
I really can't emphasize how important an impedance measurement tool is. I even discovered a Focal speaker's woofer wasn't working this way. A break in the inductor very close to the board was absolutely invisible, so if you plan on doing anything, invest in DATS or the REW jig (cheap).
In the 1980's Electrolytics were a lot worse than they are now, especially in terms of ESR. If you want to upgrade with a modern bi-polar and add parallel film that works great.
Another experiment, thanks to the late great Speakerdoctor, is to use a small value copper foil cap around the smaller film caps. Around 0.1uF TruCopper ($20 each I think). Yeah, Mundorf MKP are almost the same size as the default Focal caps so a good alternative. Also much better sounding IMHO. The issue with Mundorf Supreme's is they very much have their own sound. While the Focals are strident, MKPs are dark, and Supreme's are over saturated. Great if that's what you want to hear, but definitely distinct. Also, the Mundorf MKP's are CHEEEEAP so a great way to go for a beginner.
In the 1980's Electrolytics were a lot worse than they are now, especially in terms of ESR. If you want to upgrade with a modern bi-polar and add parallel film that works great.
Another experiment, thanks to the late great Speakerdoctor, is to use a small value copper foil cap around the smaller film caps. Around 0.1uF TruCopper ($20 each I think). Yeah, Mundorf MKP are almost the same size as the default Focal caps so a good alternative. Also much better sounding IMHO. The issue with Mundorf Supreme's is they very much have their own sound. While the Focals are strident, MKPs are dark, and Supreme's are over saturated. Great if that's what you want to hear, but definitely distinct. Also, the Mundorf MKP's are CHEEEEAP so a great way to go for a beginner.