Trumpet, a musical instrument of brass silver, or other, metal, consisting of a tube, bent twice upon itself, cylindrical for three-quarters of its length, but opening gradually out for the remaining quarter of its length into a bell mouth. Owing to its shape and the length of the column of air, the trumpet has a peculiarly rich sound, and the many modifications introduced during and since the 18th century, though increasing its compass have tended to take away from the beauty of the sound. These changes have been in the direction of adding pistons, slides, and valves. The trumpet is very ancient; the "lituus" was its Roman equivalent and was used for cavalry calls, and the trumpet, without complications, is still used for the same purpose. The modern form of the trumpet dates from the 15th century, and the instrument is very effective in a military band, and also for orchestral purposes.