sound quality out of alpine speakers

So, I'm guessing it's probably my speaker amplifier.. but the sound quality out of my 600 dollar speakers suck. The bass is sloppy, treble is not very clear.. the 150 dollar coaxials powered by the headunit sound better than the 600 dollar ones powered by an amp..

Here's my setup:

Headunit: Alpine iDA-X001

Front speakers: Alpine SPX-17 Pro w/ crossovers
Front speaker amp: Hifonics Titan TXi-4008 (80 dollar amp.. running 100watts to each side)

Rear speakers: Alpine Type-r coaxials, powered by headunit

I have adjusted the amp so it's set on High pass, and leveled around like 100hz... but still sounds like frequencies below are going through, and they sound really sloppy. There is no Bass boost turned up either.

Can anyone help me out?

Oh and just to inform, I recently just purchased a gallon of Second skin spectrum, 36 sq ft of overkill, and 2 speaker tweaker kits. My speakers were pretty much sitting in a hollow door, so I'm hoping that purchase helps a little..

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SQ for life.

So I have an update..

I tuned the bass down a little lower, they sound okay.

I'm guessing it has to be the quality of the songs. Every song i purchased through Itunes sounds fantastic. Every song i downloaded like I'm not supposed to do sounds terrible. So i guess that answers my question.

Also, I turned up the headunit volume pretty high, and the rear speakers are distorted hella bad. So i think i'm going to turn it up until i hear the distortion, then turn up the amp gain higher to get sound more out of the front speakers. That should solve my issues.

Am I correct?

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SQ for life.

First off, I am amused by your sig line: "SQ for life"... I had to laugh at that claim, I'm sorry...

Secondly, the source of the music files won't make any difference... "Like I'm not supposed to do" has nothing whatsoever to do with it. It's the ripping process, and or the initial recording process. MP3 is a notoriously AWFUL distribution format... it just is. The ripping cannot be controlled by people that are sharing their files, you have no idea what kind of processing they may or may not have added. Everything you are getting from iTunes is M4A format, and it IS marginally better than MP3. (STILL not SQ, by any stretch of the imagination, however. It is still a compressed file format - compressed music sounds like arse - end of story.)

Anyway, the lack of power on the fronts is due to the fact that they are powered by (at the VERY best) mediocre power. Put a good amp on them, and they'll sound much better. HiFonics USED to be far better gear than it is now; welcome to the NEW swap-meet!

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."