Coming from a 2008 Lexus LS with a Mark Levinson 19 speaker system, listening to the Sony in my SHO is a big step down. So, I am looking to upgrade, starting with speakers and seeing what happens after that. I realize that this can be a rabbit hole.....been there done that. However, I'm not unreasonable, and my standards are flexible. For one, I have ZERO interest in bass that rattles the licence plates and shakes the rear view mirror. However, I DO like good, solid bass that complements the track/song. I found the other speakers are muddy and at higher volumes, treble and mids are harsh and shrill. Based on numerous posts here and elsewhere, I have decided on: 1. 5x7 components for the front doors, (replacing the tweets in the sail panels). About to pull the trigger on a set of BLAM speakers. Terrible name, phenomenal speakers. Made in France and engineered by Guy Bonneville - former sound engineer at Focal. They even look like Focals. 2 5x7 Hertz Energy coaxials for the rear doors, which I have already purchased. 3. 3.5 inch center channels front and rear. Looking at Kicker coaxials. 4. Sub - not sure yet. I was going to do Tang Band 6x9 subs, but I don't think 6x9's will give satisfying bass - even with a better quality version of a 6x9. I am leaning towards a sub box, possibly passive. Again, I'm not looking to impress the neighbours.....just my ears. Later down the road, I may add/replace the amp. One thing at a time. Has anyone used the factory sub amp to power a sub box? I thought the factory amp had a separate channel for the sub, but from what I've read and seen, the sub is powered by a completely separate amp and located beside the other amplifier. for the 3.5 speakers, I understand that just about anything will fit in the rear, but the dash is a bit more restrictive? True? Any tricks? Any and all input is as usual, appreciated.