Since its foundation, in 1814, the piano workshop has had different affiliations: Hosseschrueders, Hosseschrueders y sobrinos, and Hazen, as well as various addresses in the city: Hortaleza, Luna, Valverde, Plaza de Bilbao, Fuencarral, Andrés Segovia, Juan Bravo and, finally, Arrieta. The Dutchman Jan Hosseschrueders Melsen and his nephews, Juan and Pedro Hazen, give life to the workshop, winning medals at the industrial exhibitions of 1827, 1828, 1831 and 1842, awarded by King Ferdinand VII and Elizabeth II. He closes the workshop to dedicate himself solely to marketing, going from manufacturing 150 pianos in a decade to importing 300 a year. Currently, they have in Las Rozas one of the largest private collections of pianos in the country and in Europe.