During the restoration and conversion of Schloss Freudenstein in Freiberg to the “Saxon Mountain Archive and Mineralogical Collection" pinta phonestop V acoustic panels were installed in a pargeted fashion and, though unseen, provided for an atmosphere of resonant acoustic clarity throughout the entire structure. A particularly satisfying result was that, on the basis of the intended use and the actual structure of the building, we were able to meet the highest standards in energetics and acoustics in the historical section of the building. The type of acoustical system that was needed was one that could be fully integrated into the existing structure. The Architects AFF from Berlin designed a jointless wall area. pinta phonestop V was used in a white plastered application; pinta phonestop V, made of sintered recycled glass, added merely 5,5 cm onto the existing wall. The rendered finish is smooth, does not become chalky, and is able to withstand mechanical stress, thereby enabling the acoustic exploitation of the entire wall area - all the way from the ceiling to the floor. One can only listen to the accomplishment with astonishment