You know, when I first got into car audio in the 1980s, things were much simpler, as far as interfacing the system with the control systems of the vehicle. Today, if you are driving a car from the last few decades? You will need modules to make your car stereo compatible with all the different computer systems in your vehicle. Be aware of this, no matter where you buy your stereo from. Also, if you have a quality head unit from the factory, amplifier(s) can normally be hooked up to them. Rock on! read more