Auralex! The sound company I worked for in the 1990s used this product in some night clubs including a very large amount of Sheetblok to keep sound from getting in or out of a club in Laguna California on South Coast HWY which was once a Lodge of some sort, Elks I believe. The final sound figures came in -6dB less than the city requirement. The only mistake made not by us was the Fire Doors at the back of the space. After my boss was adamant to the customer, they still failed to have the steel door frames filled with sound deadening material. We were making the final EQ of the night club sound system (at around 3AM). I played a CD by Queen of the Hammond B3, Shirley Scott and the musical selection "When A Man Loves a Woman". The pedal bass tones not only to our awe seemed to shake the building, but the fire department claimed it also shaking the apartments directly behind. The Good Ole Days! :D