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.
The anatomy of the cymbal plays a large part in the sound it creates. A hole is drilled in the center of the cymbal and it is used to either mount the cymbal on a stand or straps (for hand playing). The bell, dome, or cup is the raised section immediately surrounding the hole. The bell produces a higher pinging pitch than the rest of the cymbal.