Contrabass bugle

The contrabass bugle (usually shortened to contra or simply called the marching tuba) is the lowest-pitched instrument in the drum and bugle corps and marching band hornline. It is essentially the drum corps' counterpart to the marching band's sousaphone: the lowest-pitched member of the hornline, and a replacement for the concert tuba on the marching field.

It is different from the other members of the marching band and drum corps hornlines in that it rests on the shoulder of the player, rather than being held in front of the body. Because the contrabass bugle can get in the way of commonly worn headgear, such as a shako, it is not uncommon for contrabass players to wear a beret instead of whatever else the rest of the ensemble is wearing for headgear. This also gives the players some distinction from the rest of the brass ensemble.

The first contrabass bugle was developed in the 1960s by Whaley Royce, a Canadian instrument manufacturer which produced bugles for many drum corps of that era. Matching all other competition bugles at the time, these early contrabass bugles were pitched in the key of G, making them significantly larger than all tubas to that date, save the large E♭ and BB♭ concert tubas used in all brass bands.

The contrabass bugle is the only member of the drum corps bugle line that has never been produced in a valve-less style, as it was developed when the drum corps rules allowed one piston valve and one rotary valve. They changed to fit new rules along with the rest of the drum corps hornline, first receiving two vertical (or in this case, slanted for ease of use) piston valves, then 3 and later 4 valves to make the instrument fully chromatic.

Equivalent instruments in the key of BB♭ and CC were produced by instrument manufacturers for marching bands who wished to possess the sound of these contrabass bugles, generally regarded as "darker", without losing hornline sonority by having the basses in a different overtone series from the rest of the hornline (or requiring marching tubists to learn another set of fingerings for tuba parts originally written for BB♭ and CC instruments).

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