High pass filter for LSi9

blehmbo
blehmbo Posts: 179
edited December 2012 in DIY, Mods & Tweaks
After hearing what sounded like my LSi9s bottoming out during some bass heavy scenes in War of the Worlds (ran full range parallel with a subwoofer filling in below the speakers) I started wondering if integrating a high pass filter into the crossover of the lower frequency driver would be beneficial. Ideally I would like for it to start rolling off anywhere around 60hz or at least have a steeper roll off at 50hz. The bass from the LSi9s isn't very clean in the lower frequencies anyway, so I figured not much would be lost. Any input relating to how this could be achieved or if it's even feasible is welcome.

Here's a link to the LSi9 schematic in the vintage forum:
http://www.polkaudio.com/forums/attachment.php?attachmentid=18677&d=1155780535

I have a Yamaha AVR paired with a Rotel RMB-1075 and the volume was set to -20 when the sound occurred, turning the volume down to -25 made it disappear. I do not want the AVR to perform bass management for my front L&R speakers + subwoofer since the AVR is only used for HT, and my stereo preamp is used for everything else.