Résumé |
The saxophone is one of the wind instruments with the largest side holes. The pads, inserted inside the key play an important role on the acoustics of the instruments. The first role of a pad is to seal the side hole when it is closed. However, a lot of musicians and instrument makers consider that they have an important role on the timbre of the instrument. Indeed, early in the history of the saxophone, “resonators” (as they are called by both musicians and craftsmen) appear. These are flat disks made of metal or plastic fixed in the middle of the pad. In order to understand the role of these “resonators”, measurements of the input impedance of a cylinder topped by a key with interchangeable pads (with and without resonators) are performed. Significant differences between pads with and without “resonators” are highlighted for small key heights. A study of the vibrations of the pads shows that these differences can be explained by the high mobility of the pads without “resonator” which appear to be in practice “stiffeners”. Measurements on a whole saxophone show that the consequence of such differences on a saxophone is limited. |