For those thinking about upgrades, a bit of reflection from my upgrade path:
1. Replaced Front and rears with Hertz Components for front DSK165.3, Coax for rear - this was for about 3 years
2. All within the last 6 months, ive been chasing a better sound, Installed Pioneer 1004
3. Butyl, Foam Rings, Close Cell Foam
4. Audison APBX aS10
5. Mosconi 6to8 DSP
Its sounds good to me now. A solid 7.5/10, with maybe a bit more to come with DSP tuning. Actually enjoying listening to any kind of music now.
I would say:
1. I wouldnt bother replacing front and rear speakers unless your are upgrading everything
2. For cheapest/bang for buck, I would start with Butly on doors with Close cell foam, and Foam rings on speakers to seal the speakers, and do what you can with Head unit EQ settings
3. 1004 makes the sound stronger but i would not say that much better as the freq/EQ remains harsh but more powerful??
4. Adding the subwoofer really made a big difference, however music sounded very 'flabby', undefined, and unballanced
5. A dsp is a must if you want to get the most out of the system, full range, hear every note, feel every kick drum, and bass line.