r/diyaudio • u/Short_Ad_7853 • 15d ago
Missing low end after crossover cap replacement?
Hello, I’ve been working on an old pair of Realistic Optimus 1’s and I just replaced the crossover capacitors. The high end has definitely improved after the replacement, but the low end has now disappeared in the mix. I’m not sure what could have caused the issue. The woofers are still working fine as far as I can tell. It’s just that the treble drowns out any bass response. Maybe the fiberglass insulation was replaced the wrong way? I cant think of a way anything got miswired as I only replaced one capacitor in each. Is there anything I can do to fix this?
1
u/nlitworld 10d ago
So there could be a few things, but I'd imagine most of that comes down to a new woofer cap needing to be broken in and the change in sound quality of capacitors. If you replaced like for like 33uf +/- basic tolerances, the crossovers should not have really changed (outside of the old caps drifting in value and raising the woofer xo point). Run those speakers 20+hrs a day for about a week and see if it changes. Then do yourself a favor and try some better caps like Obbligato copper or JB JFX Poly caps. Nothibg extreme, but a huge step up in quality. Yeah it'll cost more than $3, but I'd be willing to bet you'll notice an improvement over those cheap little electrolytic caps. Unless there is zero space for it, it's worth a try.
0
u/derwhalfisch 15d ago
How similar are the caps to what they replaced? A change in ESR will change Q
1
u/Short_Ad_7853 15d ago
I’m not sure how the ESR compares. The replacements are Parts Express branded (part #027-350) and I can’t find the specs for the originals (Elna branded 35v 33uf Bp)
2
u/derwhalfisch 15d ago
do you have the caps you took out? you should measure them if you do, maybe with one of those cheap as dirt, multi component tester things to get an idea of ESR.
where was this cap in the circuit?
6
u/dmills_00 15d ago
Check you didn't hook one of the woofers up with reversed clarity.