The FEI also does not allow the Dr. Bristol. Both Dressage and Eventing disciplines allow the Dr Bristol in our U.S. national competitions My suggestion is that for USEF National Eventing Competitions we accept the same bits that USEF National Dressage competitions do in the interest of keeping it simple.
Percussion Instruments. Bass Drum - The bass drum is a percussion instrument and is the lowest and largest member of the drum family. Bass drums are used in orchestral music as well as marching bands. Cymbals - Percussions are music instruments that are either struck, shaken or scraped and may or may not have pitch. Cymbals are a perfect example of a non-pitched percussion instrument. The type that is used in marching bands is called crash cymbals.
Some tubas are capable of being converted into a marching style, known as marching tubas. A leadpipe can be manually screwed on next to the valves. The tuba is then usually rested on the left shoulder (although some tubas allow use of the right shoulder), with the bell facing directly in front of the player. Some marching tubas are made only for marching, and cannot be converted into a concert model. Most marching bands opt for the sousaphone, an instrument that is easier to carry and almost always cheaper than a true marching tuba.