it is normal to have a low pass filter on a sub. the high pass is there to keep the 6x9 woofer from overexcursion because it can't really play below 35hz. probably not too performant below 50hz, honestly.That's interesting it's filtered on both ends.. I thought I had seen a thread with a possible way to modify this via forscan... Luckily the Dayton's frequency response is 36 to 1,100Hz, so based on what you're saying it wouldn't matter if following the OP's method.
Ford does this on all their B&O systems, 35hz high pass. Most of them use a 8" woofer and larger amp, we have something unique for the Mav.
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