Originally Posted by
TJElite
I'm not saying that headunit manufacturers lie, but...
Toby
That's what you're CLEARLY saying Toby

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On top of the fact that you don't have to worry about the low power output of those internal amps, you have a lot less noise and clearer sound (as long as you have good wires that are set up PROPERLY).
Take advantage of and fine tune the crossovers built into most amps, thus allowing you to raise the volume even higher while protecting your speakers AND making them sound "better". (better being a subjective term)