Next step for my system?

I just got a new F150 truck and made some upgrades from my last system.

* I have a Alpine 9807 & Alpine 6 disc CD changer * MTX 564 (I am guessing around 70 watts x 4 for 3 homs) feeding boston's Pro60's in the front and in the rear (mini door) * MTX 502 (500 x 1) feeding a kicker 10" sub (I guees thier base model?).

I listen to metal. I am getting good sound out of my system now. However some of my music is not the best recording quality, so I would like to make some adjustments for certain CDs.

I am not educated about equalizers, crossovers, preamps, processors ect. Any suggestions on what to add next or change? I know it is a wide open question, but if you had $300 to $500 what should be my next step?

I had some major sound problems when I got it installed. I had upgraded all my speakers and the sub amp. I did not get a good sound, I was very frustrated after spending all that money. I had MTX truck box speakers that I thought sounded better. But then after spending time with the manufactures I found out that my installer never turned off my head unit power. That made a world of difference. Boston was a huge help and was willing to spend the time with me.

An Audio Control EQS would be my next upgrade in this system (aside from a Eclipse cd player of course). Let's use what you have first.

www.audiocontrol.com

The Three.1 will allow you to tweak everything from up front. The EQS would probobly mounted by your amplifiers (out of reach of tweaking). I would probobly get the EQS if you think you will be doing alot of tweaking (which it sounds like you will) and the EQS if you will just set it and forget it. If you have the room up front you could maybe fiberglass a mount that puts it in reach of the drivers seat.

Some of the music I am getting my highs and lows too far appart and not enough mids. I would like to be able to put the mids more up front. It is only on some of the CDs that are not of the best recording. I guees during some music put some more crunch in the guitar or little deeper vocals.

I looked at the EQS specs and saw that it has a remote hook up. What is that for. Can I bipass the EQS with this remote control? Also reading up on it, it talks about having more amprage to get better power out of the amps. Will this give me better sound quality. The THREE.1 only has two imput channels, the EQS has six. Since my Alpine has 6, I would want the EQS for the best sound and flexability?

What are the differences. A crossover cuts out frequencies to allow only certain high or lows to the amps. A EQ boosts or cuts the true sounds?