Passive noise control refers to methods and materials used to reduce unwanted sound without the use of electronic devices. This can include soundproofing materials like acoustic panels, insulation, and mass-loaded vinyl, which absorb or block sound waves. These materials are often used in buildings, vehicles, and studios to create quieter environments. Unlike active noise control, which uses technology to cancel out sound, passive noise control relies on physical barriers and sound-absorbing materials. It is commonly applied in home theaters, music studios, and industrial settings to enhance comfort and improve sound quality by minimizing external noise interference.