Hello, I have a 2004 base mini cooper hardtop that I bought about 3 years ago used. The car came with the HK system but te amp was fried when I bought the car. It seems these things go bad quite often. After buying the car I went to best buy and had them remove the amp and hu and put in a pioneer hu bypassing the old amp. That hu just went bad and I getting a new Sony hu installed today. I've noticed the front speakers distort at medium to high volume. Is this because there is no amp and not enough power? How much better would the setup sound if I replaced the HK speakers and added an amp? Thanks in advance!

 

You might be getting distortion because the HK speakers are 2 ohm. MOST head units aren't stable at 2ohm.

As for the second questions. You will always get better sound over factory with quality speakers and a nice amp.