Wow this thread keeps filling up with more and more HORRIBLE advise 
. I don't even know if I should bother correcting it. Never heard of a twitter lol. The brands that are being recommended are crucifiable. AND FOR CHRIST SAKE ... what the hell is hardcore rattling in reference to extreme loud? Are you a retard? Never mind that was a rhetorical question. 
The entire idea of rear fill is to simply add sound in the rear. The only time you do components rearward is when you have a large vehicle, like a SUV, or doing a surround setup like 4.1 or 5.1 Dolby. Also if you care about the rear passengers lol. If you use the rear deck you can make a sealed pod, ported or IB (infinity baffle) whatever sounds better for the application. The reality is to maximize rear fill you have to angle them or "toe them in" torwards the front. Bouncing sound off glass is gonna sound like **** regardless. You can also do some custom fiberglass work in the rear doors, along with cutting sheet metal. I will say it again... if you front speakers don't satisfy you, keep working on the front stage. You might have to spend upwards of $250 on components and more on an amp to get what you are looking for. Time alignment works friggin wonders. A lot of upper end decks have them built in. Eclipse has it even in the lower line I believe. Alpine took it a step further with being able to use a mic and correct it by a computer.
. I don't even know if I should bother correcting it. Never heard of a twitter lol. The brands that are being recommended are crucifiable. AND FOR CHRIST SAKE ... what the hell is hardcore rattling in reference to extreme loud? Are you a retard? Never mind that was a rhetorical question. The entire idea of rear fill is to simply add sound in the rear. The only time you do components rearward is when you have a large vehicle, like a SUV, or doing a surround setup like 4.1 or 5.1 Dolby. Also if you care about the rear passengers lol. If you use the rear deck you can make a sealed pod, ported or IB (infinity baffle) whatever sounds better for the application. The reality is to maximize rear fill you have to angle them or "toe them in" torwards the front. Bouncing sound off glass is gonna sound like **** regardless. You can also do some custom fiberglass work in the rear doors, along with cutting sheet metal. I will say it again... if you front speakers don't satisfy you, keep working on the front stage. You might have to spend upwards of $250 on components and more on an amp to get what you are looking for. Time alignment works friggin wonders. A lot of upper end decks have them built in. Eclipse has it even in the lower line I believe. Alpine took it a step further with being able to use a mic and correct it by a computer.
