The Wagner tuba, also known as the Bayreuth tuba, is a brass instrument that was invented by Richard Wagner for use in his operas. It is a unique instrument that looks like a cross between a French horn and a tuba, with a conical bore and a wide bell.

The Wagner tuba was first used in Wagner’s opera Das Rheingold, which premiered in 1869. Wagner wanted a new sound for his orchestra that would blend the richness of the horn with the power of the tuba, so he created the Wagner tuba to achieve this effect. The instrument was played by four musicians, each with a different pitch: the bass Wagner tuba in B-flat, the tenor Wagner tuba in E-flat, the baritone Wagner tuba in F, and the contrabass Wagner tuba in C or B-flat.

The Wagner tuba is similar in design to the French horn, with a wide bell and a conical bore. It is played with a cup-shaped mouthpiece and has a range that extends from the bass clef up to the treble clef. The instrument is usually made of brass, but can also be made of silver or gold.

One of the most famous uses of the Wagner tuba is in the Ride of the Valkyries from Wagner’s Die Walküre, where it is used to create a rich, powerful sound that is both majestic and ominous. The instrument is also featured prominently in other Wagner operas, such as Tristan und Isolde and Parsifal.

The Wagner tuba is not commonly used outside of Wagner’s music, but it has had an influence on later composers. Gustav Mahler, for example, used the instrument in his symphonies, and it has also been used by other 20th-century composers, such as Richard Strauss and Igor Stravinsky.