Physical and perceptual differences between two trumpets of the same model type

For large-scale musical wind instrument manufacturers, the ability to produce instruments in a repeatable fashion is essential. In this paper, two mass-produced trumpets of the same model type are compared in terms of physical and perceptual differences. Input impedance and bore profile measurements show significant acoustical differences due to the presence of a tiny leak in the bore of one of the two instruments. Psychophysical tests demonstrate that these acoustical differences do not necessarily result in perceptible differences in the playing characteristics of the two trumpets. Only a small number of trumpet players successfully distinguish between the instruments when subjected to a playing test, although those that do are shown to be able to provide distinct and consistent quality assessments for each one

Investigating the consistency of woodwind instrument manufacturing by comparing five nominally identical oboes

For large-scale woodwind instrument makers, producing instruments with exactly the same playing characteristics is a constant aim. This paper explores manufacturing consistency by comparing five Howarth S10 student model oboes. Psychophysical testing involving nine musicians is carried out to investigate perceived differences in the playing properties of the two Howarth oboes believed to be most dissimilar. Further testing, involving one musician and combinations of the five oboes, provides information regarding the relative playabilities of the instruments at specific pitches. Meanwhile, input impedance measurements are made on the five oboes for fingerings throughout the playing range and their bore profiles are measured. The main findings are (i) the two instruments used in the preliminary psychophysical testing are perceived as identical by most of the musicians, although differences are identified by two players when playing the note F6 and by one player when playing in the lowest register, (ii) a variation in the playability of F6 across the five oboes is due to differences in the elevation of the C key, and (iii) variations in the playing properties in the lowest register are related to input impedance differences which, in turn, appear to be at least partly due to bore profile differences

Active control applied to wind instruments

Musicians have always been interested in the evolution of their instruments. This evolution might be done either to adapt an instrument’s quality to musicians’ and composers’ needs, or to enable it to produce new sounds. In this study, we want to control the sound quality and playability of wind instruments, using modal active control. The modal active control makes it possible to modify the input impedance (frequency, gain and damping) of these instruments and to modify the instrument’s quality. The simulations for a first experiment are presented here. We simulate a control of the modes (frequency, damping) of a cylinder, which is considered as a simple ”wind instrument”. We consider the use of a microphone, a speaker, an observer and a controller to modify theses modes, then we look at the modifications on the sound and playability using Modalys. Our next goal will be to apply the control to a real cylinder, and to evaluate it in a musical context with a musician

Investigating oboe manufacturing consistency by comparing the acoustical properties of five nominally identical instruments

For large-scale musical instrument makers, the ability to produce instruments with exactly the same playing characteristics is a constant aim. Modern acoustical measurement techniques (such as acoustic pulse reflectometry and input impedance measurement methods) together with psychoacoustical testing, can help this goal be reached. This paper investigates the issue of instrument manufacturing consistency by comparing the acoustical properties and the perceptual qualities of five Howarth S10 student oboes. Input impedance measurements have been made on the five oboes for fingerings throughout the standard playing range of the instrument, acoustic pulse reflectometry has been used to measure the bore profiles of the oboes, and nine musicians have taken part in a two-alternative-forced-choice discrimination playing test using two of the instruments. The main findings are (i) the instruments are perceived as identical by most of the musicians tested, (ii) a variation in the playability of the note F6 experienced by two of the musicians is shown to be due to differences in the elevation of the pad above the C hole, and (iii) some small variations in the playing properties in the first register of the instruments are shown to be related to differences in input impedance which, in turn, appear to arise from small differences in the bore profiles of the instruments

Simulations of modal active control applied to the self-sustained oscillations of the clarinet

Modal active control enables modifications of the damping and the frequencies of the different resonances of a system. A self-sustained oscillating wind instrument is modelled as a disturbance coupled to a resonator through a non-linear coupling. The aim of this study is to present simulations of modal active control applied to a modeled simplified self-sustained oscillating wind instrument (e.g. a cylindrical tube coupled to a reed, which is considered to approximate a simplified clarinet), incorporating collocated speaker, microphone and a reed. The next goal will be to apply this control experimentally and to test it with musicians

Simulations of modal active control applied to the self-sustained oscillations of the clarinet.

This paper reports a new approach to modifying the sound produced by a wind instrument. The approach is based on modal active control, which enables adjustment of the damping and the frequencies of the different resonances of a system. A self-sustained oscillating wind instrument can be modeled as an excitation source coupled to a resonator via a non-linear coupling. The aim of this study is to present simulations of modal active control applied to a modeled self-sustained oscillating wind instrument in order to modify its playing properties. The modeled instrument comprises a cylindrical tube coupled to a reed and incorporates a collocated loudspeaker and microphone; it can thus be considered to approximate a simplified clarinet. Modifications of the pitch, the strength of the harmonics of the sound produced by the instrument, and of the oscillation threshold are obtained while controlling the first two resonances of the modeled instrument

An active mute for the trombone

A mute is a device that is placed in the bell of a brass instrument to alter its sound. However, when a straight mute is used with a brass instrument, the frequencies of its first impedance peaks are slightly modified, and a mistuned, extra impedance peak appears. This peak affects the instrument’s playability, making some lower notes difficult or impossible to produce when playing at low dynamic levels. To understand and suppress this effect, an active mute with embedded microphone and speaker has been developed. A control loop with gain and phase shifting is used to control the damping and frequency of the extra impedance peak. The stability of the controlled system is studied and then the effect of the control on the input impedance and radiated sound of the trombone is investigated. It is shown that the playability problem results from a decrease in the input impedance magnitude at the playing frequency, caused by a trough located on the low frequency side of the extra impedance peak. When the extra impedance peak is suppressed, the playability of the note is restored. Meanwhile, when the extra impedance peak is moved in frequency, the playability problem position is shifted as well

Effects of internal resonances in the pitch glide of Chinese gongs

The framework of nonlinear normal modes gives a remarkable insight into the dynamics of nonlinear vibratory systems exhibiting distributed nonlinearities. In the case of Chinese opera gongs, geometrical nonlinearities lead to a pitch glide of several vibration modes in playing situation. This study investigates the relationship between the nonlinear normal modes formalism and the ascendant pitch glide of the fundamental mode of a xiaoluo gong. In particular, the limits of a single nonlinear mode modeling for describing the pitch glide in playing situation are examined. For this purpose, the amplitude-frequency relationship (backbone curve) and the frequency-time dependency (pitch glide) of the fundamental nonlinear mode is measured with two excitation types, in free vibration regime: first, only the fundamental nonlinear mode is excited by an experimental appropriation method resorting to a phase-locked loop; second, all the nonlinear modes of the instrument are excited with a mallet impact (playing situation). The results show that a single nonlinear mode modeling fails at describing the pitch glide of the instrument when played because of the presence of 1:2 internal resonances implying the nonlinear fundamental mode and other nonlinear modes. Simulations of two nonlinear modes in 1:2 internal resonance confirm qualitatively the experimental results

Investigating the consistency and quality of musical wind instrument manufacturing

For large-scale musical wind instrument manufacturers, the ability to produce instruments in a repeatable fashion is essential. However, despite the tight manufacturing tolerances used, professional musicians are often able to discern small, but perceptible, differences between the playing characteristics of instruments manufactured in an identical way. These differences are most likely a result of tiny disparities in bore profile or in the positioning/sealing of any side holes. This talk outlines a programme of work designed to investigate the consistency with which manufacturers are able to make wind instruments and to explore the causes of any musical differences between the instruments. State-of-the-art techniques will be used to measure the internal geometries and resonance characteristics of batches of nominally identical instruments. Meanwhile, the musical qualities of the instruments will be established through a series of psychoacoustical tests. The potential effectiveness of the proposed approach will be demonstrated through a set of measurements made on two low-cost, mass-manufactured trumpets

Investigating perceptual differences between two trumpets of the same model type

Two mass-produced trumpets of the same model type have been shown to exhibit significant acoustical differences due to the presence of a tiny leak in the bore of one of the two instruments. In this paper, psychophysical experiments are presented which demonstrate that these acoustical differences do not necessarily result in perceptible differences in the playing characteristics of the two trumpets. In particular, during a listening test, very few musicians discriminate successfully between sounds produced by each trumpet. Similarly, only a small number of trumpet players successfully distinguish between the instruments when subjected to a playing test, although those that do are shown to be able to provide distinct and consistent quality assessments for each one