The bass trumpet is a type of low trumpet which was first developed during the 1820s in Germany. It is usually pitched in 8' C or 9' B♭ today, but is sometimes built in E♭ and is treated as a transposing instrument sounding either an octave, a sixth or a ninth lower than written, depending on the pitch of the instrument. Although almost identical in length to the trombone, the bass trumpet possesses a tone which is harder and more metallic than that of the trombone. Although it has valves and the same tubing length as a trombone, the bass trumpet is very different from the valve trombone. Note that certain modern manufacturers offering 'tenor horns' in upright shape, 'valve trombones' and 'bass trumpets' are actually using the same valve cluster, bell, tubing and bell flare, just bent differently - in these cases the bass trumpet would be identical to the valve trombone. Wikipedia [ - ]

The bass trumpet is a type of low trumpet which was first developed during the 1820s in Germany... [ + ]