LSi15 crossover mod.

McLoki

While I am waiting on the parts for my LSi7 mod to come in - I have been trying to plan out my LSi15 mod.

According to Polk - it crosses over from the 5.25" woofer to the 8" woofer at 150hz. (in the LSi25 it crosses over to the 10" woofer at 80hz). I also noticed that in the LSi25 it crosses over at 12db per octave instead of the more gradual 6db per octave used in the LSi15....

From looking at the schematic, it seems to use the 130uf caps to perform the high pass and low pass functions for this. If I wanted it more in the 100-120 range, what value cap would I need to make that happen also if it was done, would I need to slope it at 12db per octave rather than the 6db per octave it is set at now? (it is low pass filtered at 12db per octave in both speakers, it is just high pass filtered at the faster 12db per octave in the LSi25.)

Face

You can try larger caps, such as 150-160uf, but the correct way to do it would to also increase the inductor sizes. I'm currently installing air core inductors along with all film caps in a pair of LSi15's and can tell you it's a real PITA.