The lowest pitched tuba, pitched in C or B flat (often referred to as CC and BB flat based on a now-obsolete octave naming convention). The CC tuba is used as an orchestral and concert band instrument in the USA, but BB flat tubas are the contrabass tuba of choice in German, Austrian and Russian orchestras. In the USA, the BB flat tuba is the most common in schools (largely due to the use of BB flat sousaphones in high school marching bands) and for adult amateurs.