I have installed a jvc hdr1 deck while maintaining the stock speakers and I am a little discouraged about the sound (98 gsr btw). I can't tell if it's better or not. I cant turn it up as loud without it distorting with this new deck. It starts sounding bad at around 28, which isn't really loud, when the deck is capable of going up to 50. The mids and highs distort pretty badly. I have adjusted the built in eq, but it doesn't seem to help. I'm hoping that it's just a speaker matter and not my HU. Is it possible that sound quality could degrade with an aftermarket HU? It's got to be the stock speakers right?

 

Probably the speakers. You ARE giving them a bit more power now.

 

change out the speakers, stock speakers can only handle at most 3-5 watts rms, once u change them out, listen to em for like a month and then, add a 4 ch if u want