The trumpet is often confused with its close relative the cornet, which has a more conical tubing shape compared to the trumpet's more cylindrical tube. This, along with additional bends in the cornet's tubing, gives the cornet a slightly mellower tone, but the instruments are otherwise nearly identical. They have the same length of tubing and, therefore, the same pitch, so music written for cornet and trumpet is interchangeable. Another relative, the flugelhorn, has tubing that is even more conical than that of the cornet, and an even richer tone. It is sometimes augmented with a fourth valve to improve the intonation of some lower notes.