I agree. Custom speakers sound better. My standard factory car speakers are average. A friend of mine used to be a radio tech. He felt like a change of scenery, and is now doing electronics for some government department. He custom built his own car hi-fi. In car dvd entertainment system. Replaced all of his speakers.
Installed a nice premium quality amp. Plus a heavy duty capacitor. This capacitor is shaped as a pipe, and is a foot long by about 3 or 4 inches in diameter.

He demonstrated a " Pink Floyd " dvd movie live concert. The screen slid out smooth like silk, and into the vertical position. Then he cranked his custom audio system. I had a good listen and was drooling over the sound quality. It was just exquisite.
He enjoyed my reaction, because my face expression was that of spellbound. :drool: My factory car hi-fi is pale and mediocre in comparison. I am partial to global trance music. If i had a decent custom install, that global trance would sound glorious. I am very careful with the base adjustment. The problem being is that i like my trance music loud in the car. The volume is cranked up, and the trance is ever so joyous and uplifting when out on a cruise. :happy:
The maximum volume is 40. I have to keep the base down low. The volume is set to to 37 or 38 as a limit. I tried 40 with a bit of base, and there is far too much distortion. YUK! If i would have continued, there was a danger of damaging the factory speakers. Factory installed car speakers will never cut the mustard. :shrug: