The Grotrian Concert Royal Add-On from Pianoteq features an authorized modeled version of the Grotrian Concert Royal grand piano, an instrument originally developed with the help of prominent pianists, such as Clara Schumann, Franz Liszt, and Anton Rubinstein. The piano itself is known for the attention given by the Grotrian company to its tone production, playing mechanism and construction, which allows the instrument to meet the very highest standards of quality and refinement. Today, the pianos are still hand made in Germany, with the production of each instrument taking eight months. The add-on requires Pianoteq version 5.8 or above.