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An acoustical ceiling tile having an improved sound absorption value and having a dual layer of acoustical materials. The base mat layer has either no mineral wool or a low mineral wool content. The surface layer has a high mineral wool content which provides improved sound absorption values with or

An acoustical ceiling tile having an improved sound absorption value and having a dual layer of acoustical materials. The base mat layer has either no mineral wool or a low mineral wool content. The surface layer has a high mineral wool content which provides improved sound absorption values with or without perforating or fissuring the tile. The dual layer acoustical ceiling tile has a noise reduction coefficient (NRC) value of at least about 0.50.

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1. A dual layer acoustical ceiling tile made in a water-felting process having an improved sound absorption value (NRC) comprising a low mineral fiber content base mat containing less than about 50% by weight of mineral fiber and having a thickness ranging from about 0.25 inch to about 0.625 inch an

1. A dual layer acoustical ceiling tile made in a water-felting process having an improved sound absorption value (NRC) comprising a low mineral fiber content base mat containing less than about 50% by weight of mineral fiber and having a thickness ranging from about 0.25 inch to about 0.625 inch and a mineral wool fiber-rich overlay surface layer containing at least about 75% by weight of mineral wool fibers and having a thickness ranging from about 0.125 inch to about 0.5 inch, said ceiling tile having a noise reduction coefficient (NRC) value of at least about 0.50.