Baritone{Top} Euphonium{Down} You can see they are much alike but Baritone had only 3 valves while euphonium had 4 valves. Baritone is different than any other instrument on the planet that might attract such a name, and they had a family that was bigger. So, they needed a name for it. Someone sees an advertisement for a tenor tuba with a maker's model name, the Euphonium just to avoid confusion. Consequently, tenor tubas in the U.S. used the term they always used, which is "baritone". All the old music is marked thus. The typical American baritone differs from an English euphonium in no more ways than a typical American tuba might differ from a British or German tuba. So, with all due respect to experts like Dr. Werden, saying a euphonium has a large bore and an (American) baritone a small bore, and they are therefore different instruments, is like saying an American tuba, which its wide taper, is more or less a tuba than a British tuba, with its narrower taper.