In my case: I have found that the Bose system in C5 Corvettes (I have two) is just barely okay. However if you provide a "good clean" audio input via the AUX channel that you get much better sound out... da! And if you add an external amp along with some good rear speakers and a sub you can have MUCH better sound. I feed the MP3s into the HUs from in car computer and/or iPod.
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