filters on speaker cables


I have a slightly long winded question on adding filters to my speaker cables to bleed of low frequencies. So is it possible to add a filter to each speaker cable to lessen to load on the amp when reproducing low frequencies? And if so what value,where do I get them, and how do you install them? I would like to add a stereo pair of quality subs to my system. I am using a Modwright KWI 200 integrated amp with Tyler Acoustics Woodmere II Speakers. I love the sound of the integrated but no way to add a crossover to the system as is. There are many here that say adding subs and lessening the load on the amp and main speakers has great results, so much so, that I really want to try it. So I am looking for another option without buying separates. Any advice is greatly 
mizike
No such animal. If you want to use a sub with line level you will have to go with a separate amp and preamp.
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Thanks fellas, this is what I thought the response would be, I was just hoping someone knew more than I and had a solution. I will continue so save my meager wages to some day step up to good separates and the save even more to try the subs. I seem to have my heart set on reducing the load on the amp and main speakers, maybe I'll rethink that, thanks again, Allen.
Most subs have a built in crossover that will limit the base going to your main speakers. Do a search for subs and you will find many with built in crossovers
Alan
"Most subs have a built in crossover that will limit the base going to your main speakers. Do a search for subs and you will find many with built in crossovers"

True that most subs have a built in crossover, however, it is generally a low pass filter that has no effect on bass to the main speakers. A few do have a high pass filter that is necessary to limit the bass to the main speakers, and it is usually a line level connection. Speaker level high pass filters are rarely used nowadays.

I don’t understand how bass could be a problem. Four woofers in large cabinets that are spec'ed to 25 Hz with 400 watts per speaker, since they are 4 ohm. I’m thinking there is a problem elsewhere.