4x6 and 6.5 is a pretty large size gap. As all ready said the best set up will come from having speakers all the same size. IMO the best set up for a Jeep is 5.25" all around with a sub (all amped of course). Personally I have infinity kappa 5.25 in the front and 6.5" in the back because I don't want a sub taking up space and figuring out where to put another amp that wont die from water. For me the bass is fine.
I have the nalin brackets in the front with coax speakers. If I were to do it again I would also get the nalin tweeter brackets and components. Right now the front highs struggle because the dash speaker covers are so stifling and point sound down.
Correct. 5.25"s all around will be the most acoustically correct...and by far the easiest to install for 03-06 guys.
Just upgraded my sound system - happy to help where I can. 70+ mph, wide open top (half doors)... VERY nice sound! Currently designing quick disconnects so I can quickly slide bottom tray w/amps out for off-road.
As you can see on one of the last pics, I did use the Kicker 5.5" component in the roll bar mounts. Side view to show wrap around speakers that are the Quad Pod set up.
2 Quad Pods (rear 8" sub w/wrap around 6.5") each w/:
8" Kicker CompR Subwoofer
6.5" Component Speaker System
2 Versa Pods (front) each w/:
4" Rockford Fosgate Prime
2 Mod Pods (front under door) each w/:
5.5"' Kicker Coax Speaker
Polk makes some 50w 4x6's that are great for the dash speakers. They are also marine grade, so they won't mind getting a little wet. The 40w have the tweeter that sticks out too far and they won't mount properly without spacers.
4x6's suck it don't matter if they are made of gold. they suck. you will get much better sound quality and a much bigger sound range from a 5.25. imo if you are working on a tj using nalin brackets and some 5.25 components are the only options. i have installed multiple sets for customers and the difference from them to a set of 4x6's is night and day.
the only way i would stick with 4x6's in a jeep is if you have a yj and cant fit a lager size. in that situation do like i am going to do and put some 6.5s in the half doors like i am with quick discos.