A euphonium is a medium sized, three or, usually, four valve, conical_bore, tenor-voiced brass instrument that is part of the tuba family. It closely resembles the baritone horn, in both appearance and range, except that the bore of the latter is smaller and mostly cylindrical, its sound is brighter, and the fingering is different because it has only three valves. Both are commonly used in marching and concert bands, but infrequently in orchestral music. The euphonium's sound has been described as dark, rich and smooth.