The tuba is the largest and lowest-pitched member of the brass family. It was patented in 1835 by Wilhelm Friedrich Wieprecht and Johann Gottfried Moritz in Prussia. Before the tuba, orchestras used instruments like the ophicleide or the serpent for bass support, but these were often difficult to play in tune and lacked the power needed for growing Romantic-era orchestras. The tuba uses a system of valves (either piston or rotary) that change the length of the tubing when pressed, allowing the player to reach different notes. Its wide conical bore gives it a deep, mellow, and resonant sound. Tubas come in various pitches, such as BBb, CC, Eb, and F. In a marching band, a specialized version called a sousaphone is often used, which wraps around the player's body and has a forward-facing bell to project sound over the crowd.