The following material was reprinted from…… https://www.yamaha.com/en/musical_instrument_guide/trumpet/selection/ “Timbre will vary with the quality of the material The timbre of a wind instrument is determined by the way in which the air inside it vibrates. Hence, the timbre depends not only on the shape of the instrument and the length of its tube but also to a subtler degree on the quality of the material of the vibrating tube. The varying composition of brass Brass is the most commonly used material for making “brass” instruments such as the trumpet. Brass is an alloy of copper and zinc and has long been…