Why do you need to do interior sound insulation before modifying the car stereo?

Because the sound insulation is not unidirectional, but bidirectional. How to understand it? The first one is to prevent the sound of the car stereo from spreading to the outside, but this is the second one. The most important thing is to prevent the noise outside the car from entering the car.

We all know that listening to high-grade stereo at home generally requires the room to be as quiet as possible in order to hear many details of music. If the environment is noisy, the details of music will often be disturbed by noise, which will affect the listening experience.

This is why car stereos need sound insulation.