On some voicing adjustments of flue organ pipes
A. W. Nolle · The Journal of the Acoustical Society of America · 1978
An adjustable organ pipe for research is described. The section is rectangular. Micrometer screws control (1) the width of the air jet opening, (2) the height of the edge, and (3) the in-out position of the air jet relative to the edge, all of which are practical voicing parameters. Modular part replacements can change the resonator length, the edge shape, and the shape of the air jet passage and the jet edges. The present survey describes the behavior of open and stopped pipes in the two-dimensional adjustment space defined by (2) and (3) above. Contours are shown for the limits of sustained oscillation, for sound pressure level, for deviation of frequency from the passive resonance value, and for the onset of abnormal modes of operation including reversion to the edge tone frequency, overblowing, multimode oscillation, and exaggeration of anharmonic content.