Tuba as is the case with Berlioz). In most of Europe, the F tuba is the standard orchestral instrument, supplemented by the CC or BB only when the extra weight is desired. Wagner, for example, specifically notates the low tuba parts for "Kontrabasstuba," which are played on CC or BB tubas in most regions. In the United Kingdom, the E is the standard orchestral tuba. The euphonium is sometimes referred to as a tenor tuba and is pitched in B, one octave higher than the BB contrabass tuba. The term "tenor tuba" is often used more specifically to refer to B
Brass instrument valve by Heinrich Stölzel in 1815) was an early variety. The piston valve found in the majority of valved brass instruments was invented in 1838 and patented in 1839. They are sometimes called Périnet valves after their inventor, François Périnet. They work by diverting air obliquely through ports in the stock of the valve so that a loop of tubing is included in the air stream, lowering the pitch. The stock of the valve is cylindrical and moves up and down through a larger cylindrical casing. The rotary valve works using a short circular plug housed in a larger cylindrical casing.