ADDT is an organic quadratic diffuser. This diffuser improves sound clarity and ambience while increasing the overall perceived space of the room. The range of the Art Diffusor® is extended over other designs by its unique organic curvature to further control specular reflections above 4 kHz. The Model D Art Diffusor deflects the sound hemispherically, a result of the bicubic concentric rings, and the various quadratic well depths.