Tuba after American bandmaster John Philip Sousa, resembles a hélicon with the bell pointed up (in the original models as the J. W. Pepper prototype and Sousa's concert instruments) and then curved to point forward (as developed by Conn and others). Some ancestors of the tuba, such as the military "bombardon", had unusual valve and bore arrangements compared to modern tubas. During the American Civil War, most brass bands used a branch of the brass family known as "saxhorns", which, by today's standards, have a narrower bore taper than tuba—the same as true cornets and baritones, but distinct from trumpets, euphoniums,
Brass instrument characteristics. Trumpets, trombones, and tubas are characteristically fitted with a cupped mouthpiece, while horns are fitted with a conical mouthpiece. One interesting difference between a woodwind instrument and a brass instrument is that woodwind instruments are non-directional. This means that the sound produced propagates in all directions with approximately equal volume. Brass instruments, on the other hand, are highly directional, with most of the sound produced traveling straight outward from the bell. This difference makes it significantly more difficult to record a brass instrument accurately. It also plays a major role in some performance situations, such as in marching bands.