Euphonium are the tuba-euphonium quartet or larger tuba-euphonium ensemble; the brass quintet, where it can supply the tenor voice, though the trombone is much more common in this role; and other mixed brass ensemble. Such ensembles are almost non-existent: they are more likely to be semi-professional or amateur in nature. Most of the United States Armed Forces service bands include a tuba-euphonium quartet made up of players from the band that occasionally performs in its own right. The euphonium is not traditionally an orchestral instrument and has not been common in symphony orchestras. However, there are a few works from the
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.