Meh, just saying that once you disable the Sony processing you get a far more natural sound and pure output and from there, new more efficient and better sounding speakers go a long way with the power it has too. In any case, you should do this first before adding gadgets you may not need, depending on your tastes. Sure, if you are a 1% audiophile, there's always more you can do, absolutely, I just don't see the need personally and disabling of Sony processing and far better speakers should always be the first place to start anyway.
Given that the car is rented often and my sound settings haven't been changed, I might be onto something. Of course everybody ears or should I say how you were taught to listen to music is different.
Factory speakers are cheap and have low sensitivity. Then again Infinity speakers sound better but have even lower sensitivity (in the lower 80's db 1w/1m). These are popular upgrades in both cars.I find Morels to be overpriced for what your getting. If you're going down that road, Audio Fogs are worth a look but again I find it hard to spend nearly $500 for seperates when Hertz lower end products work extremely well and are very efficiency speakers.
Also adding an amp gives you some protection from overdriving the speakers in the form of a high pass crossover.
More power and a crossover when turning off the factory protection and sound shaping is the correct move. I'd take it even a step further and look at Kicker's Key amp which offers auto EQ using a mic.
The system also suffers from a lack of deep bass.When I play songs that should pound, it doesn't... The stock speakers do a decent job but a sub improves sound so much more than some of the other options mentioned