Upgrade speakers or head unit.

[boostin_7]

A mate of mine said the guy he lives with got awesome results by amping the stock speakers & running a sub in the rear.
He reckons the stock speakers pump, its just that they're under powered from the stock setup

 

[mike1303]

Your friend hasn't seen a stock speakers magnet vs an aftermarket one
Hell, if they blow up it's no loss!

 

[boostin_7]

Yeah he didn't see the speakers but heard it & said it was pretty decent. .. he does the audio in all his cars so id take his opinion as alright.
It was in a 2013 st if that makes any difference.

 

[silvernavman]

I'll be honest, the stock speakers are paper based dual cone speakers. They are average. A simple speaker upgrade makes some difference but no doubt an amp plus head unit etc would be much better again