I don't know much about bass blockers but my mids distort from low bass when the volume is up and it sounds like crap.

 

If you want a simple first order filter (6dB/octave) all you need is the following formula.

C = 1 / 2 x Pi x f x R

C = capacitance in micro farads (uf)
Pi = 3.1416
f = cutoff frequency in Hertz
R = impedance of the speaker (For a Monsoon mid-woofer this would be 2ohms or 4ohms for a typical after-market speaker)

So for a cutoff of 100Hz you would plug in the following figures for a Monsoon mid-woofer...

C = 1 / 2 x Pi x 100 x 2

C = 796uf or 800uf

You would then connect the capacitor in series with the speaker in the + wire.

If you want a steeper rolloff you would need a 2nd order filter (12dB/octave) which adds an inductor to the filter.

For a 2nd order Linkwitz-Riley high pass filter you would use the following formulas...

C = .0796 / R x f
and
L = .3183 x R / f

C = Capacitance in micro farads
L = Inductor in milli-henries
R = Impedance of the speaker
f = the desired cutoff frequency

So for a 100Hz cutoff using a 2ohm Monsoon mid-woofer...

C = .1796 / 2 x 100

L = .3183 x 2 / 100

C = 898 uf
L = 6.37 mh

 

I forgot to mention that for a capacitance that large you would probably need to use several smaller values in parallel with each other.

 

or just try a few sets from a local best buy and call it a day, rather than trying to figure out what the heck mr wizzard is trying to say.

look man i don't mean to make fun but its a FACTORY sound system, not a 10k billy bad a-- set up.

prob a 100 or 150 hertz should fix your issue though, a sub would be a good idea to back fill the missing bass range. and yes you can ad a sub to a factory system with out going crazy.