Acoustics and the vented trumpet

Vented trumpets with three or four finger-holes are widely employed in the performance of music originally written for natural trumpets without finger-holes. The way in which these finger-holes are used differs from the use of tone-holes on the cornett, the keyed trumpet and the keyed bugle. In general, vented trumpets are designed to approach the timbre of natural trumpets while facilitating control of intonation and accuracy in playing. In the present paper, the acoustical foundations for the function of the three- and four-hole systems are explored. The study draws on input impedance measurements and playing tests of typical vented and natural trumpets. Parameters quantifying the timbre of vented trumpets are compared with corresponding values for natural trumpets.