The organ is in a continued state of evolution, tonally and mechanically, designed by the builder to meet certain expectations related to the musical aesthetics of the time. Organ building in the United States has been influenced by both European organ building traditions and American innovations. During the early twentieth century, Ernest M. Skinner emerged as one of the greatest organ builders in America. Throughout his life, Skinner's quest was to create an "ideal organ," capable of playing a variety of music. Skinner's vision was rooted in the Romantic Movement and influenced by the dynamic gradations and rich, colorful sonorities of orchestral and operatic music of the era. A number of technological developments were applied to the design of the organ which made the romantic organ possible. The prominent European organ builders of the nineteenth century created organs that defined the romantic-style instrument in their respective countries. By the end of the century, American organ builders were creating their own versions. Skinner traveled to Europe to learn what he could from the foreign builders. Skinner built organs that synthesized European and American elements, along with his own innovations, as continuation of nineteenth-century trends that brought the romantic-symphonic organ to its fullest realization. Additionally, Skinner developed many new organ timbres, including a number of stops that imitate various orchestral instruments. The result of Skinner's creative work is the the American symphonic organ. This paper attempts to illustrate how the tonal designs of organs built by Walcker, Cavaillé-Coll, and Willis influenced the work of Skinner and the American symphonic organ. The work of each builder is discussed with descriptions of their designs. The designs and innovations of Skinner are examined as related to these European builders. A number of organ specifications are provided to supplement the information presented here. Today, American symphonic organs, particularly those built by Skinner, are revered for their warmth and charm and are inspiring the work of present day organ builders who are incorporating elements of this style into their own designs.