at what frequency does sound become directional and if i wanted to go to about 400-500hz would that be too directional to be mounted underneath a seat

 

I have no idea what mustang is going to allow you to mount a speaker under any seat but yes that is a little high. If you want more midbass then try to either make an enclosure for your current speakers, or even try to add some sound damping and make an enclosure out of the door. I made enclosures for my 6.5s in my stang, I show how to do it on my trucks cardomain page. You can get to it from my mustangs page in my sig

 

ttocs do your kickpanel enclosures get in the way of the clutch pedal and how deep is the enclosure. im looking more to fill the gap between the sub and my comps my components sound better hp at 125 but the gap in sound is apparent so ilv kept them hp at 70 thought some dedicated middbass speakers would help solve this problem

 

I believe sound starts to become more directional around 300..... THINK.....

 

I am aware of my kicks when I drive so I don't put my foot through them but the only real loss was of the dead pedal.

My midbass enclosures are my 6.5s in the doors.

 

i kno i just want to kno how much space i have to make a pod on the kick panel

 

should i go with kicker ss midbass speakers or kicker cvt 6.5 subs?

 

the kick panels were not made with the enclosure in mind. The angle that the speakers are pointing and 10X more important then the enclosure that the 4" has.

I have never been a fan of kicker and because of this have never looked at any of their product lines. I would not know what of thier stuff to recomend since I would not own it.