I added an lc7i line out converter to a budget pioneer 5 ch amp, speakers and slim 12" sub. Coupled with some cheap dynamat and foam acoustic panels it sounds great. Problem with the FiST is a lot of road noise to overcome.
Replacing the head unit is not OEM quality, you lose steering wheel controls and the metra dash unit is ugly. Or you can add a digital signal processor (DSP), but $$$. Any other solutions are piggybacks and you lose steering wheel controls.Unfortunately, You can't just 'drop-in' a new head unit in most newer cars.
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