Lsi25 ( remodeling)

AndonAndon Posts: 2
Hi to all polk lovers. I am new in this forum and I hope you guys can help me out with something that I am planing to do. I am proud owner to set of Lsi25 and I love them. The problem is that I am tired paying for amp repairs, always something with the amps! My idea is to replace the ams with simple aluminum plate with banana jack connectors, add low pass filter for the sub, use the existing mids and high crossovers, and use them as a passive speakers. Is anyone done something lake that? Will it work? And last but not least any suggestions for low pass filter?


  • K_MK_M Posts: 1,617
    edited January 5

    Welcome to the forum!

    You could always leave the amp in speaker, and run the sub directly to a stand alone sub amp, such as those that Parts Express carries.

    The stock lsi25 sub volume is only a bit over one cubic foot, mostly due to the very narrow width of the speakers, so active EQ is applied to keep response even in the deep bass range.

    So the deep bass will be much lower in volume if you run them passive.

    Many stand alone sub amps though will have a similar bass boost. I believe it is 6db at 30-35 Hz.
    Lsi15, Lsi9, LsiC,Rta11t,M5jr+,M4, SDA SRS 2.3TL, Rti6....Still listing stuff, a work in progress.
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  • mlistens03mlistens03 Posts: 2,664
    You could also use one of the Crown XLS series amplifiers. Not something you want to use for your mid/treble, but will serve you well for those subs, not to mention they are stable into 4 (and I think even 2) ohms. They have EQs built into them as well, IIRC. :)

    This was something I thought about doing when I had LSis. I never got around to it though, and the one sub was more than enough for my room. :)
    Not Tom or Trey or Jim just Micah
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    I've always thought the goal of high-end audio was not to have your neighbors bang on the wall and say, 'Turn that darn music down' but to have your neighbors bang on the wall and say, 'Tell your friends to go home and you can practice later this week'.

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  • AndonAndon Posts: 2
    Thank for the advice, as of now I run the lsi25 mids and highs only with separate sub. The speakers are powered by 2 outlaw mono blocks ( 300w per channel in 4 ohms) and they do fine. I just have the feeling that I don't use the speakers full potential that way. I am starting to think just to fix the amp and replace them with something else. Currently have my yes on 5.0 set of RBH. So, if someone wants a full set of Lsi series masage me for price. The set will include two Lsi25, ( left and right) one LsiC, two sets of Lsifx (surround on wall speakers) and sub Psw1000.
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