2015 Silverado stereo upgrade
 

So... Wanting to upgrade my stereo. The stock system has 6 speakers - 2 in the dash, 2 in the front door and 2 in the rear door. Are the speakers in the dash considered tweeters and connected to the front door speakers? Most amps have front, rear and sub.
OR
Has anyone attempted to add a powered sub and not bother to amplify the stock speakers. I know there are LOC out there but I cant get a straight answer from anyone on how installing a LOC will affect the stock speakers if they are not amplified or if they will be affected at all.
Also curious to get anyone's opinion. BTW - not a 20yr old looking to piss off the neighbors on the other side of the block. looking on adding a nice, compact 8" just to add a nice tight base. I mostly listen to Alt Rock, Kid Rock and the likes. Not looking to rattle fillings loose. Trying to do this on a budget.
Any help is appreciated

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