Adolphe Sax
Adolphe Sax and the modern maker Robb Stewart have built examples of soprano ophicleides an octave above the bass. Currently, only five contrabass ophicleides are known to exist. Three are in museums, and two are privately owned: one in Portland, Oregon and one in Petaluma, California. Those in private hands were both made by Robb Stewart and are the only playable examples.