So I installed an Alpine CDA-9883 a few months ago

 

6 1/2's aren't made to have bass cranked on them. What your hearing is distortion from feeding the speaker a "clip" from the internal amp of the headunit. You should get an amp first off , but if you looking for more bass you need a sub.

 

The "overpowering" sound is probably not the speakers and probably the Alpines internal amplifier distorting.

 

yes that's called a "clip" that's when the top of the sound spectrum hits the roof rather than doing a smooth wave.