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 where it is then directed through the second valve and out the bottom. This type of valve, however, had inherent problems. It forced the air to double back on itself and the 90 degree turns disrupted the bore, causing significant undesired back-pressure. These problems were improved upon later by the double-piston valve. Brass instrument valve Brass instrument valves are valves used to change the length of tubing of a brass instrument allowing the player to reach the notes of various harmonic series. Each valve pressed diverts the air stream through additional tubing, individually or in conjunction with other valves. This