Have just measured the capacitance of a NP 33uF using LIMP, here is the result 32.9106uF
Attachments
The small capacitor in parallel with the large non-polarized capacitor mitigates the effects of inductance in the large capacitor. A small capacitor is usually used across the series NP capacitor for the tweeter, but is not needed across the shunt NP capacitor for the woofer.
Ed
sadly it would seem darwinism is no longer working.
even if we take out the protections the smart have put in place, the stupid are able to reproduce faster than they die out.
we need licenses to drive, but reproduction is a free for all.
Licence to die ? (dixit James Bond)
Notice reproduction is still a part of Darwinism and selection process ...if the Dead was muting we would make a movie of that.
Notice reproduction is still a part of Darwinism and selection process ...if the Dead was muting we would make a movie of that.
Last edited:
Concerning the voltage rating of the cap, 35VAC or 50VDC is enough for 100W at 8 ohms or 200W at 4 ohms. There are huge quality differences in NP electrolytics. The ones i like to use in higher end build are the German Mundorf or ERO caps. It all depends on the power levels the xover will be dealing with, which is even more important when choosing the inductors if they have a magnetic core. With air core inductors, you just have DCR as a potential issue to deal with and sometimes it works out in your favor.
Film cap reliability is a non issue if the voltage rating is over 100V DC. Sound wise they're too close to call if you're dealing with a quality brand. Comparing two different brands in SQ is almost impossible. There are some very subtle differences with smaller film caps between dielectric materials when they're used in the HP filter of a high efficiency driver. Its a minute discrepancy and the differences are typically not repeatably noticeable to most people when a blind AB test is done. I just buy the brand thats on sale at any given time, but I generally go for the same brand as whats already used in the xover. I do prefer polypropylene over mylar when used in series with compression drivers.
Film cap reliability is a non issue if the voltage rating is over 100V DC. Sound wise they're too close to call if you're dealing with a quality brand. Comparing two different brands in SQ is almost impossible. There are some very subtle differences with smaller film caps between dielectric materials when they're used in the HP filter of a high efficiency driver. Its a minute discrepancy and the differences are typically not repeatably noticeable to most people when a blind AB test is done. I just buy the brand thats on sale at any given time, but I generally go for the same brand as whats already used in the xover. I do prefer polypropylene over mylar when used in series with compression drivers.
There is no need to do that. They are already doing that to themselves.
Carefully designed crossover network is all it takes. NPE's or other kinds of caps, is less relevant, if at all.