Search Results (35)

In this paper, a set of digital signal processing (DSP) procedures tailored for the analysis of complex musical tones with prominent inharmonicity is presented. These procedures are implemented within a MATLAB-based application and organized into three submodules. The application follows a structured DSP chain: basic signal manipulation; spectral content analysis; estimation of the inharmonicity coefficient and the number of prominent partials; design of a dedicated filter bank; signal decomposition into subchannels; subchannel analysis and envelope extraction; and, finally, recombination of the subchannels into a wideband signal. Each stage in the chain is described in detail, and the overall process is demonstrated through representative examples. The concept and the accompanying application are initially intended for rapid post-processing of recorded signals, offering a tool for enhanced signal annotation. Additionally, the built-in features for subchannel manipulation and recombination enable the preparation of stimuli for perceptual listening tests. The procedures have been tested on a set of recorded tones from various string instruments, including those with pronounced inharmonicity, such as the piano, harp, and harpsichord. Full article

Chinese traditional instruments are diverse and encompass a rich variety of timbres and rhythms, presenting considerable research potential. This work proposed a deep-learning framework for the automated classification of Chinese traditional instruments, addressing the challenges of acoustic diversity and cultural preservation. By integrating two datasets, CTIS and ChMusic, we constructed a combined dataset comprising four instrument families: wind, percussion, plucked string, and bowed string. Three time-frequency features, namely MFCC, CQT, and Chroma, were extracted to capture diverse sound information. A convolutional neural network architecture was designed, incorporating 3-channel spectrogram feature stacking and a hybrid channel–spatial attention mechanism to enhance the extraction of critical frequency bands and feature weights. Experimental results demonstrated that the feature-fusion method improved classification performance compared to a single feature as input. Meanwhile, the attention mechanism further boosted test accuracy to 98.79%, outperforming baseline models by 2.8% and achieving superior F1 scores and recall compared to classical architectures. Ablation study confirmed the contribution of attention mechanisms. This work validates the efficacy of deep learning in preserving intangible cultural heritage through precise analysis, offering a feasible methodology for the classification of Chinese traditional instruments. Full article

This article discusses the innovative application of a Cartesian robot manipulator with acoustic feedback for calibration and precise positioning of a string-excitation element in investigating stringed instruments. It describes an experiment in which an acoustic guitar string is automatically excited with different guitar picks. The robot’s end effector positioning system utilizes limit switches, acting as a mechanical sensor, which provides feedback to the linear actuators that are equipped with stepper motors. The authors detail the research challenges they faced and propose a positioning algorithm that makes use of a microphone as an acoustic sensor, improving the calibration of the end effector’s position. Full article

The mechanical properties of music wire are contingent upon its microstructure, which in turn influences its applications in music. Chinese stringed instruments necessitate exacting standards for comprehensive performance indexes, particularly with regard to the strength, resilience, and rigidity of the musical steel wires, which differ from the Western approach to musical wire. In this study, SWP-B music wire was selected for investigation through metal heat treatment, which was employed to regulate its microstructure characteristics. Furthermore, a spectral analysis was conducted to evaluate the musical expression, encompassing attributes such as pitch and timbre. In conclusion, the governing law of the impact of the microstructure of music wire on its musical expression was established. The results demonstrate that steel wire subjected to a 200 °C annealing treatment for cementite spheroidization can effectively reduce stress concentration, thereby reducing the probability of fracture and consequently improving tonal uniformity and richness while increasing tensile strength from 2578 MPa to 2702 MPa. Conversely, the high-temperature annealing treatment alters the crystalline structure of the material and refines the grain structure, thereby improving the material’s performance and sound quality. The fine microstructure of the music steel wire displays enhanced uniformity. As the annealing temperature increases, the strength of the ferrite phase <110>//ND (<010>//ND, indicating that the <010> direction of the crystal is parallel to the normal direction of the material) and the cementite phase <010>//ND demonstrates a gradual decline. However, this also results in a more pronounced harmonic performance, which, in turn, affects the overall music expression. Full article

A number of rectified nylon harp strings, having the same nominal diameter, were subjected to different sequences of applied stress steps. Each string was tested continuously for several weeks to allow sufficient time for the stretching responses to be clearly observed. Qualitatively, much of the observed behaviour was in accordance with established expectations. However, the quantitative data gathered here are believed to be novel, and revealed some surprises. The strings displayed a combination of elastic stretching, fully recoverable viscoelastic stretching, and apparently non-recoverable plastic stretching. The elastic and recoverable viscoelastic stretching behaviour was quite straightforward, but the plastic creep behaviour was more complicated, with a number of the strings displaying an unanticipated phenomenon. When the applied stress was left unchanged, or was stepped down and back up again, it was noticed that, in some cases, the extent of the subsequent plastic stretching, when the applied stress was next increased beyond its previous maximum, was significantly less than might have been expected. The tests revealed that this apparent plastic creep ‘constraint’ mechanism seemed to depend primarily on the length of time between successive overall rises in the applied stress, with a threshold somewhere in the range of 30–40 days. It is suggested that this phenomenon may be due to a gradual increase in the polymer crystallinity during this rest period. Two of the strings, which were tested over a wider range of applied stress levels, revealed another aspect of the creep behaviour. There appeared to be an initial ‘straightening’ phase during which the plastic stretching rose with the applied stress in a diminishing manner to reach a stretching limit. As the applied stress was increased, this initial straightening was overtaken by an unlimited main stretching phase, which rose slowly at first before approaching a linear increase with the applied stress. Full article

Violin is one of the most complex musical instruments to learn. The learning process requires constant training and many hours of exercise and is primarily based on a student–teacher interaction where the latter guides the beginner through verbal instructions, visual demonstrations, and physical guidance. The teacher’s instruction and practice allow the student to learn gradually how to perform the correct gesture autonomously. Unfortunately, these traditional teaching methods require the constant supervision of a teacher and the interpretation of non-real-time feedback provided after the performance. To address these limitations, this work presents a novel interface (Visual Interface for Bowing Evaluation—VIBE) to facilitate student’s progression throughout the learning process, even in the absence of direct teacher intervention. The proposed interface allows two key parameters of bowing movements to be monitored, namely, the angle between the bow and the string (i.e., α angle) and the bow tilt (i.e., β angle), providing real-time visual feedback on how to correctly move the bow. Results collected on 24 beginners (12 exposed to visual feedback, 12 in a control group) showed a positive effect of the real-time visual feedback on the improvement of bow control. Moreover, the subjects exposed to visual feedback judged the latter as useful to correct their movement and clear in terms of the presentation of data. Although the task was rated as harder when performed with the additional feedback, the subjects did not perceive the presence of a violin teacher as essential to interpret the feedback. Full article

The design of musical instruments is a discipline that is still carried out in an artisanal way, with limitations and high costs. With the additive manufacturing technique, it is possible to obtain results for the generation of not only electrical but also acoustic instruments. However, it is necessary to generate a procedure to evaluate the influence of the process on the final result of the acoustics obtained. This study focuses on investigating the relationship between the construction of acoustic guitars and their final sound. The reinforcement structures at the top of the instrument are analysed, as well as how this design affects the vibratory behaviour of the top in the first five vibratory modes. Specifically, this article presents a procedure for the design of customised acoustic guitars using additive manufacturing through parametrisation and a vibrational analysis of the designed tops using finite element (FEA) and experimental physical tests, in order to develop a methodology for the study of stringed instruments. As a result, an 11% increase in the high-frequency response was achieved with a printing direction of +45°, and a reduction in the high-frequency response with ±45°. In addition, at high frequencies, a relative error of 5% was achieved with respect to the simulation. This work fulfils an identified need to study the manufacture of acoustic guitars using polylactic acid (PLA), and to be able to offer the musician a customised instrument. This represents a breakthrough in the use of this manufacturing technology, extending its relationship with product design. Full article

Cretan lyra is a stringed instrument very popular on the island of Crete, Greece, and an important part of its musical tradition. For stringed musical instruments, the air mode resonance plays a vital part in their sound, especially in the low frequency range. For this study, the air mode resonance of a Cretan lyra is investigated with the use of finite element method (FEM). Two different FEM acoustic models were utilized: First, a pressure acoustics model with the Cretan lyra body treated as rigid was used to provide an approximate result. Secondly, an acoustic–structure interaction model was applied for a more accurate representation. In addition, acoustic measurements were performed to identify the air mode resonance frequency. The results of this study reveal that the acoustic–structure interaction model has a 3.7% difference regarding the actual measurements of the resonance frequency. In contrast, the pressure acoustics solution is approximately 13.8% too high compared with the actual measurements. Taken together, the findings of this study support the idea that utilizing the FEM acoustic–structure interaction models could possibly predict the vibroacoustic behavior of musical instruments more accurately, which in turn can enable the determination of key aspects that can be used to control the instrument’s tone and sound quality. Full article

The purpose of the study was to analyze the influence of the quality class and the orthotropy of wood upon the sound absorption coefficient, the reflection and the impedance ratio of two species widely used for stringed musical instruments, namely spruce (Picea abies L. Karst) and maple (Acer pseudoplatanus L.). An impedance tube for the frequency range 100–6400 Hz was used in these experimental determinations. Knowing the influence of porosity and tortuosity on the acoustic absorption, these properties were also determined, as well as the sound reduction coefficient and the maximum values of the acoustic absorption coefficients in relation to frequency. The main results highlighted the differences between the anatomical quality class of the wood within each species, but also concerning the sound direction relative to the three main sections of wood, as an orthotropic material. The article highlights the acoustic performance parameters related to the frequency of the wooden material and its relationship to density, porosity and quality class. The results represent useful information for musical instruments manufacturers and more. Full article

Music education, whether professional or amateur, includes learning musical instruments. Intonation is a critical factor in their training. The main objective of this research work is the design and validation of online educational software for the real-time training and evaluation of intonation in non-fixed pitch musical instruments, such as fretted string instruments (violin, viola, and cello) and brass instruments (trumpet, horn, and trombone). This software is intended to create a practice artefact for novice music students. A design sciences research methodology is adopted to achieve a product tested for functionality and usability. Novice students carry out the validation phase through a study consisting of previous practice with the software and the administration of a questionnaire with open-ended items grouped in technical-didactic, emotional, and overall dimensions, plus two additional questions. The results show evidence that the software was well received, confirming previous studies on the design and validation of educational music education software. Full article

Acoustical properties of various materials were analyzed in order to determine their potential for the utilization in the three-dimensional printing process of stringed musical instruments. Polylactic acid (PLA), polyethylene terephthalate with glycol modification (PET-G), and acrylonitrile styrene acrylate (ASA) filaments were studied in terms of sound reflection using the transfer function method. In addition, the surface geometry parameters (Sa, Sq, Sz, and Sdr) were measured, and their relation to the acoustic performance of three-dimensional-printed samples was investigated. It was found that a higher layer height, and thus a faster printing process, does not necessarily mean poor acoustical properties. The proposed methodology also proved to be a relatively easy and rapid way to test the acoustic performance of various materials and the effect of three-dimensional printing parameters to test such a combination at the very beginning of the production process. Full article

An integrated method, which combines Electronic Speckle Pattern Interferometry, impulse response measurements, finite element method simulations, and psychoacoustic tests, is proposed to evaluate the vibroacoustic behavior of a carbon fiber bouzouki. Three of the carbon fiber instruments are manufactured, and one is qualified via interferometric experimental measurements with reference to a traditional wooden bouzouki, which was evaluated for its sound and playability by the proposed method. Psychoacoustic tests were used to evaluate the sound and playability of the newly qualified carbon fiber bouzouki, which was further modeled by the finite element method and simulated. The simulation results agreed well with the experimental measurements. Furthermore, finite element simulation results of the qualified carbon fiber bouzouki were demonstrated with reference to the traditional wooden bouzouki experimental results, providing new findings crucial for the optimization of the manufacturing and the vibroacoustic behavior of the carbon fiber instrument. The proposed integrated method can be applied to a variety of carbon fiber stringed musical instruments. Full article

Music occupies a unique and multi-faceted role in spatial representation of the Holocaust, both in terms of documenting its horrors and in cultivating legacy. This uniqueness derives from music’s dual temporal and physical essence as it is represented by written scores that serve as a blueprint, as sonic events that fill both time and space, and as musical instruments that operate as conduits for both. String instruments, in particular, have occupied a vital place in Jewish culture and, consequently, during the Holocaust. In the most tragic sense, some of these instruments even became actual containers of genocidal evidence as with violins played outside concentration camp crematoria that filled with the human ash that fell. This article will demonstrate that, when played, these instruments transform into living artifacts and musical witnesses, with voices that can speak for those who have been silenced, and that the resulting music that resonates from the printed page fills a sonic space that serves as a powerful medium for memory and representation. The phrase “bearing witness” often refers to representing the stories of people, places, and experiences through words, either written or spoken. But material culture also has a role to play in representation. While objects, art, and architecture certainly support language-based witness, they also provide their own unique lens and conduit for testimony. This seems especially true for music, which has the ability to exist as and cross between both words and objects. Nevertheless, music as material witness remains a complex and often understudied aspect of historical testimony. As a result, this paper will explore through an interdisciplinary approach the divergent nature of music as an aural form, as a creative art, and as a cultural artifact and will offer examples of how music can enhance, elucidate, and complicate Holocaust representation. Full article

Rich intercultural music engagement (RIME) is an embodied form of engagement whereby individuals immerse themselves in foreign musical practice, for example, by learning a traditional instrument from that culture. The present investigation evaluated whether RIME with Chinese or Middle Eastern music can nurture intercultural understanding. White Australian participants were randomly assigned to one of two plucked-string groups: Chinese pipa (n = 29) or Middle Eastern oud (n = 29). Before and after the RIME intervention, participants completed measures of ethnocultural empathy, tolerance, social connectedness, explicit and implicit attitudes towards ethnocultural groups, and open-ended questions about their experience. Following RIME, White Australian participants reported a significant increase in ethnocultural empathy, tolerance, feelings of social connection, and improved explicit and implicit attitudes towards Chinese and Middle Eastern people. However, these benefits differed between groups. Participants who learned Chinese pipa reported reduced bias and increased social connectedness towards Chinese people, but not towards Middle Eastern people. Conversely, participants who learned Middle Eastern oud reported a significant increase in social connectedness towards Middle Eastern people, but not towards Chinese people. This is the first experimental evidence that participatory RIME is an effective tool for understanding a culture other than one’s own, with the added potential to reduce cultural bias. Full article

Different music training involves different hand coordination levels and may have a significant influence on brain oscillation for the executive function. However, few research has focused on the plasticity of executive function and the brain oscillation modulated by different musical instrument training modules. In this study, we recruited 18 string musicians, 20 pianists, and 19 non-musicians to perform a bimanual key pressing task during EEG recording. Behavioral results revealed that pianists have the highest accuracy and the shortest response time, followed by string musicians and non-musicians (p < 0.05). Time-frequency analyses of EEG revealed that pianists generated significantly greater theta power than the other groups from 500 ms to 800 ms post-stimulus in mid-central, frontal brain areas, and motor control areas. Functional connectivity analyses found that the pianists showed significantly greater connectivity in the frontal-parietal area in theta band based on phase-locking value analysis, which suggests that piano training improves executive function and enhances the connectivity between prefrontal and mid-central regions. These findings contribute to a better understanding of the effects of different music training on executive function. Full article