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Materials-inspired innovation for acoustic guitar design
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... In this approach, students are shown an image of how the fingers should be positioned to play a chord, together with audio of how it should sound when played correctly [21], and a camera is then used to detect the student's finger positions via corresponding finger markers. This combination of audio overlay and 3D visual information is extremely well suited to guitar teaching [22]. ...
Despite being one of the most commonly self-taught instruments, and despite the ready availability of significant amounts of didactic material, the guitar is a challenging instrument to learn. This paper proposes an application based on augmented reality (AR) that is designed to teach beginner students basic musical chords on the guitar, and provides details of the experimental study performed to determine whether the AR methodology produced faster results than traditional one-on-one training with a music teacher. Participants were divided into two groups of the same size. Group 1 consisted of 32 participants who used the AR app to teach themselves guitar, while Group 2, with a further 32 participants, received formal instruction from a music teacher. Results found no differences in learning times between the two groups based on the variables of method and gender. However, participant feedback suggested that there are advantages to the self-taught approach using AR that are worth considering. A system usability scale (SUS) questionnaire was used to measure the usability of the application, obtaining a score of 82.5, which was higher than the average of 68 that indicates an application to be good from a user experience point of view, and satisfied the purpose for which the application was created.
... The scarcity and increasing cost of many traditional back woods has pushed guitar makers to explore alternative solutions. These have included the use of less familiar species of tropical woods that are more readily available (Ellis et al., 2008), temperate woods such as maple and walnut, laminates (French and Handy, 2006), and synthetic materials such as carbon fiber or fiberglass composites (Forbes-Roberts, 2008;Pedgley et al., 2009). ...
Some of the most prized woods used for the backs and sides of acoustic guitars are expensive, rare, and from unsustainable sources. It is unclear to what extent back woods contribute to the sound and playability qualities of acoustic guitars. Six steel-string acoustic guitars were built for this study to the same design and material specifications except for the back/side plates which were made of woods varying widely in availability and price (Brazilian rosewood, Indian rosewood, mahogany, maple, sapele, and walnut). Bridge-admittance measurements revealed small differences between the modal properties of the guitars which could be largely attributed to residual manufacturing variability rather than to the back/side plates. Overall sound quality ratings, given by 52 guitarists in a dimly lit room while wearing welder's goggles to prevent visual identification, were very similar between the six guitars. The results of a blinded ABX discrimination test, performed by another subset of 31 guitarists, indicate that guitarists could not easily distinguish the guitars by their sound or feel. Overall, the results suggest that the species of wood used for the back and sides of a steel-string acoustic guitar has only a marginal impact on its body mode properties and perceived sound.
... This is an attempt to introduce soundboards with consistent tones as those from wooden materials tend to be affected by humidity and moisture content of the surrounding air as shown by Borland [2]. Research into the potential use of an industrially moulded plastic component such as the guitar soundboard is given by Pedgley et al. [33]. ...
Research has shown that the soundboard plays an increasingly important role compared to the sound hole, back plate, and the bridge at high frequencies. The frequency spectrum of investigation can be extended to 5 kHz. Design of bracings and their placements on the soundboard increase its structural stiffness as well as redistributing its deflection to nonbraced regions and affecting its loudness as well as its response at low and high frequencies. This paper attempts to present a review of the current state of the art in guitar research and to propose viable alternatives that will ultimately result in a louder and better sounding instrument. Current research is an attempt to increase the sound level with bracing designs and their placements, control of natural frequencies using scalloped braces, as well as improve the acoustic radiation of this instrument at higher frequencies by deliberately inducing asymmetric modes in the soundboard using the concept of “splitting board.” Various mathematical methods are available for analysing the soundboard based on the theory of thin plates. Discrete models of the instrument up to 4 degrees of freedom are also presented. Results from finite element analysis can be utilized for the evaluation of acoustic radiation.
... No data on damping capacity of these composites. The need for further basic studies related to the microstructure and to the acoustical properties of thermoplastic polymers and foams was stressed by Pedgley et al. (2009). The linear damping across the spectrum of audible frequencies in carbon fiber reinforced plastic soundboards is very different from the complex non linear attenuation in wood, where some frequencies are attenuated more slowly than others. ...
The development of composite materials as substitutes for wood in musical instruments was motivated by numerous factors, such as the fragility of instruments during handling and transportation, their sensitivity to temperature and humidity variations, the scarcity of wood resources (resonance spruce and tropical hardwoods), the high variability of wood material, and the very high level of craftsmanship required. We discusse the properties of composites made with synthetic and natural fibres and nanocomposites which are the newest developments. The potential and limitation of fiber reinforced composites depend on the properties of the constituents, the fibres and the matrix. The soundboards made from composite materials should match two basic requirements, the stiffness per unit length and density per unit area of an ideal material (i.e. spruce tonewood). Matching criteria were deduced from theoretical studies of the vibration of thin orthotropic plates. Based on these criteria a substitute material for the soundboard of a concert harp was produced, which is a remarkable achievement. In 2012 it was possible to produce a grand piano made entirely in composite materials. It is pleasing to note that during the last decades, numerous string instruments for advanced students or mass production instruments have been successfully produced using composite materials to replace tonewood.
... Použitím uhlíkového vlákna v kombinácii s rezonančným drevom smreka môžeme dosiahnuť zlepšenie jeho akusticko-fyzikálnych a mechanických vlastností. V súčasnosti tieto materiály čoraz častejšie nachádzajú uplatnenie pri výrobe, jednak rezonančných dosiek gitár (PEDGLEY et al. 2009), pián (BORLAND 2010, hárf (PREISSNER a ROYSTON 1998, GUNJI et al. 2012, ale aj pri výrobe ostatných komponentov týchto nástrojov, ako ich vystužovacie a iné pomocné prvky (ANONIMUS 2012). Okrem výroby hudobných nástrojov sa používajú, aj vo výrobe drevených konštrukcií pod označením FRP (Fibre Reinforced Plastic) alebo CFRP (Carbon Fibre Reinforced Plastic) materiály. ...
The work deals with the use of carbon fiber as the "new" material to practical use on the ribs of acoustic guitars. The materials that will be used for the production of carbon fiber are analyzed in the introductory parts. Next, the work deals the design of the ribs and location of carbon fiber in the experimental composite. Experimental specimens with different location of carbon layer were then subjected to a test. There was measured the static bending modulus of elasticity (Eoh) in radial and tangential direction. Bending modulus of elasticity each files, which differentiate in location of carbon layer, were mutually compared. Results showed that the carbon, in some cases, had a significant influence on increase of modulus of elasticity. Therefore, we can state that proposed material is suitable to production of acoustic guitars ribs.
Music therapy (MT) helps with various diseases through music, where the musical instrument is an essential element, defined as the tool of communication between the patient and the music therapist. Despite the first music therapists began to appear in the twentieth century, there is still a lack of proper instruments and solutions more focused on therapy, and it is usually chosen to make changes to pre-existent instruments. Through research methods, such as bibliographic investigation, interviews and product analysis, the field of MT was investigated, as well as how it can be related to design, involving concepts like emotional design, relaxation and meditation, in order to develop an instrument that can be used in MT sessions, by both therapist and patient. A swinging wood idiophone was developed with a single note, through a Design research based on practice, called innovation inspired by materials adjusting its initial shape and ergonomics according to the desired sound which aims to prolong and oscillate the sound. This paper presents the investigation and process since the definition of shape and the inherent concepts of the proposed product, to the finishes and a brief discussion.
In this study, the disadvantages of wood, which is widely employed in producing music instruments, are discussed. For example, high moisture sensitivity, low impact resistance, and time-consuming procedure as well as various properties of different species or in several parts of one specimen which are the main problems of wooden music instruments are extensively discussed in this paper. Many materials have been employed to replace with wood in many applications. The most successful ones are wood plastic composites (WPCs) which have been extensively applied in some fields due to their better moisture and impact resistances and low-cost producing procedure (Injection molding). But, finding a suitable alternative for wood with properties required in acoustic filed is relatively difficult since many considerations have to be noted when it will be utilized in music applications. Although wood particles, which are dispersed in wood plastic composites at high concentrations, induce wood properties to the resultant composite, they could not support all acoustic requirements throughout the composite. In this paper, a new generation based on polymeric composites is introduced as suitable alternative for wood in order to produce music instruments that could resolve the above mentioned problems of wood. Application of fiber composites possessing a structure as same as wood, has been developed due to their specific vibrational and acoustical properties. In general, such fiber composites are provided using various types of synthetic and natural fibers such as glass and hemp fibers, respectively, and different kinds of resins e.g. modified polypropylene, epoxy, and polyester resins. In this study, three different kinds of fibers (i.e. glass, carbon, and Kevlar fibers) were employed to produce fiber composites for replacing with wood in music applications. Also, an unsaturated isophthalic polyester resin was used as polymer matrix. All fiber composites were produced utilizing pultrusion method and their acoustic properties were then compared with two natural wood called white Mulberry and Cedar wood. Density and elastic modulus (in longitudinal direction) of all mentioned specimens, which are the main parameters to determine acoustic properties of a material, were measured and reported comparatively. Consequently, other acoustic parameters such as sound velocity, acoustic coefficient, sound quality factor (Q) and acoustic converting efficiency (ACE) were calculated and reported in comparison with those obtained from two kinds of natural wood. Although the results show that all manufactured composites have higher densities than those of natural wood, which reduce their acoustic efficiency, their considerable high moduli improve it increasingly. Therefore, much higher sound velocities could be obtained for fiber composites compared with wood. Furthermore, the composites demonstrate higher values of sound quality factor as well as acoustic converting efficiency in compared with those calculated for natural wood. From the obtained results it can be also deducted that carbon fiber/polyester composite possesses the highest value of acoustic coefficient among others which can be ascribed to the exceptional modulus of carbon fiber inducing to corresponding composite. The results reveal that carbon fiber reinforced polyester resin shows maximum performance and as a consequence could be undoubtedly used for making high performance music instruments.
Wood is one of the main materials used for making musical instruments due to its outstanding acoustical properties. Despite such unique properties, its inferior mechanical properties, moisture sensitivity, and time- and cost-consuming procedure for making instruments in comparison with other materials (e.g., composites) are always considered as its disadvantages in making musical instruments. In this study, the acoustic parameters of three different polyester composites separately reinforced by carbon fiber, glass fiber, and hemp fiber are investigated and are also compared with those obtained for three different types of wood specimens called poplar, walnut, and beech wood, which have been extensively used in making Iranian traditional musical instruments. The acoustical properties such as acoustic coefficient, sound quality factor, and acoustic conversion factor were examined using some non-destructive tests based on longitudinal and flexural free vibration and also forced vibration methods. Furthermore, the water absorption of these polymeric composites was compared with that of the wood samples. The results reveal that the glass fiber-reinforced composites could be used as a suitable alternative for some types of wood in musical applications while the carbon fiber-reinforced composites are high performance materials to be substituted with wood in making musical instruments showing exceptional acoustical properties. POLYM. COMPOS., 2014. © 2014 Society of Plastics Engineers
The authors explore perceived sound properties of acoustic guitars built with foamed polycarbonate soundboards rather than spruce or cedar. The research seeks to establish the extent to which polymer acoustic guitars are an acoustically credible alternative to wood instruments. Data are generated through participation by members of the public (n = 320) in blind listening tests. Remarkably, participants are found unable to distinguish much beyond a 50% success rate whether sound originates from wood or polymer acoustic guitars. The findings challenge deeply rooted ideas about traditional material-instrument relationships and champion the use of design as a driver for instrument innovation and artistic engagement.
The time‐domain description of musical and other nonlinear oscillators complements the more commonly used frequency‐domain description, and is advantageous for some purposes. It is especially advantageous when studying large‐amplitude oscillations, for which nonlinearity may be severe. It gives direct insight into the physical reasons for the variation of waveform as playing conditions vary, and into certain phenomena which may seem counter‐intuitive from the frequency‐domain viewpoint, such as the musically undesirable flattening in the pitch of a bowed string when the bow is pressed too hard onto the string. It is easy to set up efficient time‐domain simulations on a small computer, a fact that has been surprisingly little exploited in musical acoustics. The simplest relevant model is described here. It demonstrates some of the basic nonlinear behavior of the clarinet,violin, and flute families with very little programming effort. Remarkably, a single set of modelequations has relevance to all three cases, at a certain level of idealization, with appropriate choices of parameter values and of linear and nonlinear characteristics. For the flute family, this simplest model gives waveforms and phase relations closely resembling those observed at resonance in the organ‐pipe experiments of Coltman [J. Acoust. Soc. Am. 6 0, 725–733 (1976)], including the triangular pressure and velocity waveforms. It can be shown (again using a time‐domain approach) that the triangular waveform is a universal limiting form, independent of detailed acoustic loss mechanisms provided losses are small.
Selection of materials in engineering design is often a routine process, resulting in gradual progress. However, materials-inspired innovations are possible and can result in genuine breakthroughs. In this survey, the characteristics of the traditional design process are described, followed by a discussion of the alternative: materials-inspired innovation. Protracted competition between old and new technologies is an inevitable fact of progress, constituting the main cause of economic risk in developing and marketing a new material.
The concept of 'designerly ways of knowing' emerged in the late 1970s in association with the development of new approaches in design education. Professor Nigel Cross first clearly articulated this concept in a paper called 'Designerly Ways of Knowing' which was published in the journal Design Studies in 1982. Since then, the field of study has grown considerably, as both design education and design research have developed together into a new discipline of design. This book provides a unique insight into a field of study with important implications for design research, education and practice. Professor Nigel Cross is one of the most internationally-respected design researchers and this book is a revised and edited collection of key parts of his published work from the last quarter century. Designerly Ways of Knowing traces the development of a research interest in articulating and understanding the nature of design cognition, and the concept that designers (whether architects, engineers, product designers, etc.) have and use particular 'designerly' ways of knowing and thinking. There are chapters covering the following topics: •the nature and nurture of design ability; •creative cognition in design; •the natural intelligence of design; •design discipline versus design science; and, •expertise in design. As a timeline of scholarship and research, and a resource for understanding how designers think and work, Designerly Ways of Knowing will be of interest to researchers, teachers and students of design; design practitioners and design managers.
The relationship of science and design is not well understood or developed but is becoming the centre of the national debate concerning technology in UK schools. This article seeks to clarify issues, define terms and develop thinking in this complex area.