First off I'll list my equipment so all you guys who do/have done a lot with car audio can point me in the right direction. I have the following:

Kenwood Excelon KDC-X889 head unit
Kenwood Excelon 5.25 components in the front (not sure the model number)
Kenwood Excelon 5.25 two-way in the back (again, nothing on the model number)
Kicker 2006 ZX350.4 amp
2 x Kicker 2006 S10L5 subs
Kicker 2006 ZX1000.1 amp
1 Farad Cap

RCA's are run down the passenger side while the power and remote turn wires are run down the drivers side, which I'm afraid is causing my less than stellar FM reception but that's a whole different issue.

I have excellent highs and lows but my midrange is almost non-existent. Some types of songs sound better than others but no matter what I adjust on the amp or on the head unit I can't make it sound right. Any ideas of what I might try? A system I've spent this much time and money on should sound better than my truck that I just tossed an inexpensive Pioneer receiver and replacement speakers in and yet they sound better overall.

 

5.25" component speakers generally aren't good at midrange. If you can find room either a couple of dedicated woofers (not subwoofers), a component set, or a couple of good 6x9's would help.

If it's not, set your low-pass crossover on the ZX1000.1 to 100hz. Don't go above that on the S10L5 but it can handle 100hz.

 

I've been considering buying some good 6 1/2 components for the front. I'd like to put the tweeter in the door and take out the tweeter pod that comes in the GT as it's impossible to get an aftermarket tweeter to fit in and it's difficult to get out and back in. Also suppose 6 1/2's in the back may work also but i'm really not sure what will fit back there. I know everyone has different brand preferences and i'm liable to get 10 different answers but what would you guys recommend?

 

I don't think you can go wrong with a set of MB Quart components as long as you're pushing them with an amp.

 

dont run your speakers on full range.. not a good idea.. put them on high pass and make sure your input voltage freq is set right.. Im guessing that headhunit has a very low output so set your amp close to o.5 volts.. also keep your highpass freq dial in the centre.. avoid changing those.. still lacking midrange.?. change the eq on your headunit... to give more punch in the 2khz ro 10khz range... still dont? what you may need is some kind of acoustic dampening ... that has been found to drastically increase mid range and bass tones in low wattage speakers.. In my car I run 200watt RMS splits so I never have had much problem.. with gear like that which could only really handle 70watt rms its difficult to get the performance you want.. if you STILL cant get much luck.. upgrade to a splits system. biggest tweeter possible to keep the gap between midrange and high very minimal.... I just noticed .. you need a 3 way speaker.. particulary a 6x9 3 way.. that mill make up for any loss.. 2 ways are more or less low mid range and high.. 3 ways have the extra stiff mid sized for the mid to mid highs which will surely compensate for the fronts.... hope this helps :s goodluck