I am attempting to design a low-pass filter for a subwoofer, as the audio amplifier that is connected to it does not filter any of the sound coming in, and it is getting pumped full of high frequency sound. I have settled on a Butterworth LC filter, and want a crossover frequency of around 200Hz. I have determined that I want a capacitor somewhere in the range of 140-160 uF and an inductor in the range of 4.5-6.5 mF to hit that frequency, and from a circuit standpoint, it seems to make sense. Source: this website
Here is where I hit a difficulty. I am aware that I don't want an inductor with very much DC resistance and is rated for a high current throughput (possibly in excess of 5A). I don't know which to choose.
I also am at a loss for the capacitor to choose, as I need one which is two-way (able to handle AC), but I am not sure for the other requirements of it. If anyone can clarify these points for me, and give suggestions as to the actual parts to use, I would be forever grateful. It is also worth noting that I am on somewhat of a budget, so please try to recommend affordable products, even if they have lower performance.