The highest level soundproofing system is the most effective. It may be used in multi-apartment residential buildings and apartments of enhanced comfort, in special purpose facilities (recording studios, conference rooms, movie and concert halls, restaurants, karaoke-bars, etc.). The system reduces all frequency range sound transmission through walls and floors and ceilings and makes the sounds inaudible for humans (at the sound volume of up to 80-85 dB). The main system elements are AcousticGyps M1 boards. Airborne sound insulation index Rw = 73 dB