How cornets and trumpets differ

The lead brass instrument in many early New Orleans jazz bands was the cornet, but by the 1930s most jazz ensembles featured the trumpet. Louis Armstrong conspicuously made the transition from cornet to trumpet while at the height of his career. Although in general musicians regard the two instruments as being recognizably different, the acoustical behavior of cornets and trumpets is more difficult to distinguish. Most of the features of the two instruments, such as mouthpiece rim and cup, tuning-slide and valve section bores and bell flare, do not differ systematically; only the mouthpiece backbore and instrument leadpipe are necessarily different. This paper draws on input impedance measurements and the analysis of spectra obtained from playing tests recorded under controlled conditions to propose instrument-dependent characteristics of cornet and trumpet sounds.