im looking at adding to my system and know what i want but am a little lost
first this is what i currently have:
sony head unit
mtx speakers powered by 760w pioneer amp
12" kicker L5 powered by alpine mrp m500

first thing i wanted to do is add some midbass. im not sure whether i should get some midbass speakers or 8" subs. i know this is what the midbass is made for but i found some good priced 8" jbl subs that say they have a frequency respons of 35-500hz. this hould be good for midbass if i limit the hz right? or should i go with the midbass drivers? if i do go with midbass can i put them in a box? i was planning on making a center consuel type thing in the back as i have no door space

next i need ti figure out how to limit the frequency range. i dont know much about this other than lpf and hpfs on amps. any suggestions here would be helpful. also what would be the best range be. i was thinkin setting the L5 lpf at around 70hz then the jbls from about 70-400(maybe500) then the mids.

i also am planning on getting tweaters. again whats the best way to limit to the highs. i have an amp with a hpf but im not sure if its just to take out the sub bass?

 

What MTX speakers do you have? What car?

The 8" can do midbass duty but it is generally most effective to have midbass in the front of the car. Generally you will want to limit them to under 300hz as a ballpark starting point.

The best plan is to add a pair of amp channels for the midbass and an outboard 3way crossover.

 

im not sure of what speakers i have as they were in the car when i bought it. (so was all my wireing) is there anyway to tell which speakers they are short of taking the door panel off? i am getting an 760w sony for the midbass speakers it can put out 190w rms. i was looking and i can use it as a high pass at 80hz or whatevers best so what would be a good/cheap way to limt the top end. any specific products would be appreciated as i have been looking for crossovers and low pass filters online and cant find any in the range i need.

about them being at the front. ive heard of the whole soundsatge thing but im not really sold on it. i like the music commin from all around. how important is it to have them up front. does anyone have any ides if i have no room in my doors?

 

Look for a Coustic XM-5, XM-5e, or XM-6 crossover. This will give you a subwoofer output, a bandpassed output for your midbass, and a high pass output for your door speakers.

No harm in trying the midbass out back. It's a little unconventional but not unheard of and two of the best sounding cars on the planet had them in the back.

 

FWIW you might have an easier time installing dedicated midbass drivers as their motor structure & basket would likely be more manageable than that of a subwoofer.
Dukk's suggestion of the Coustic x-over is GREAT. It will allow you to tweak your HP cutoff to what works in your car. I just added some 8's to my front doors (PITA) and used a gentle 60/150hz, 6db bandpass which filled in my midbass wonderfully.