On the bore‐to‐driver feedback in double‐reed conical woodwinds

Abstract

The nonlinear behavior of double‐reed drivers makes advisable the use of time domain to study bore‐to‐driver feedback. The characteristic trends of the impulse response of a conical woodwind are revised. The low intensity of the reflection coming from the first open hole shows the essential role that Bernoulli pressure plays in the reed self‐sustained oscillation (also proved by the reed squeaks that players produce to check reed readiness). Time‐domain study of these instruments leads to the convolution product relating pressure and velocity at the bore input section. The use of the impulse response h(t), the plane‐wave and the spherical‐wave reflection functions, Rp(t) and Rs(t) respectively, as kernel functions in this product is revised. The sharp fluctuations of Bernoulli pressure may impair the use of Rp(t) while R s(t) is unsuitable due to the usual taper discontinuity in the staple‐main body junction of these instruments. Computed and experimental initial transients are given for the case of a “te...