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We have used Navier-Stokes-based simulations to study the spectral content of tones produced by a soprano recorder. Our focus is on the attack portion of a recorder tone and how it can be influenced and controlled by the player. We show that both the blowing speed and the time taken to initiate blowing can be used to control the amplitudes and time variations of the upper partials during the attack. Our simulations are consistent with previous experimental results reported in the literature for flue instruments and with a new analysis of tones produced by a soprano recorder. The results illustrate how a player can control the expressiveness of a recorder tone.
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Study of “half-integer” harmonics in recorder tones and some speculations about their origin
The musical notes produced by recorders and other flue instruments consist primarily of spectral components with frequencies given approximately by nf1, where n is an integer and f1 is the fundamental frequency. However, the real tones of these instruments contain other spectral components that have been observed and discussed by a number of authors. We report a study of spectral components in the tones produced by recorders that are odd half-integer multiples of f1, i.e., spectral components with frequencies n±12f1. Our results, obtained through a combination of experimental and simulation studies of soprano recorders, suggest that these components are associated with the air flow in the vicinity of the window region and the labium edge. We also show that these half-harmonics can be suppressed by modifications of the instrument that alter the pattern of air flow in those regions. Speculations concerning the importance of the half-harmonics and the degree to which they are perceptible by a listener are briefly discussed.
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- Award ID(s):
- 1806231
- PAR ID:
- 10477214
- Publisher / Repository:
- Acoustical Society of America
- Date Published:
- Journal Name:
- The Journal of the Acoustical Society of America
- Volume:
- 154
- Issue:
- 5
- ISSN:
- 0001-4966
- Page Range / eLocation ID:
- 2917 to 2927
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1121/10.0022327
