What settings do you have the head unit on for sound? With the stock speakers, I found myself setting it to "driver's seat" with the bass at neutral and treble to about 2+. I have now changed the settings to bass 1+, treble 5+ and in the "all seats" setting. I have only replaced the 6x8s with the TS-A6874Rs so far.
Sorry (Sorry-Sorry-Sorry) for answering that late - but i was working an 3.73 gears and so on.
I now prefer "All seats", Bass +3, Treble +4
I just found a few mitnutes tody this LINK
, I Think I wiill go with that, because I have a 12" Subwoofer and a 300W-Amp left
My car: 2011 V6 convertible Premium, Performance white, automatic
Mods: Pioneer&Kicker speaker, Airraid CAI, SCT-Tunes, painted mirror covers, 3.73 gears, FRPP LCA's, One-Touch-Convertible-Module, Fog lights