What Are the Three Layers of Car Sound Insulation?

[AutumnDella]

Generally, it consists of two layers of vibration damping and one layer of sound-absorbing cotton. Below are the specific details about car sound insulation: 1. First layer of insulation: Targets the internal metal panels of the door for vibration damping, effectively reducing low-frequency vibrations generated during driving. After applying the first layer, tapping the outer side of the door panel will change from a crisp sound to a dull one, showing significant improvement. 2. Second layer of insulation: Dampens the external metal panels of the door, reducing low-frequency resonance caused by vibrations. Additionally, this layer makes the door panel thicker and more sealed, enhancing the door's solidity and improving the acoustic environment for the car speakers, resulting in better sound quality. 3. Third layer of insulation: Sound-absorbing cotton is applied on top of the second layer (vibration damping board), further improving the sound insulation effect. After the first two layers reduce low-frequency vibrations, some resonance may still remain. The sound-absorbing cotton absorbs this residual resonance, ensuring a quieter cabin.