Download Estimating the plucking point on a guitar string
This paper presents a frequency-domain technique for estimating the plucking point on a guitar string from an acoustically recorded signal. It also includes an original method for detecting the fingering point, based on the plucking point information.
Download Extraction of the excitation point location on a string using weighted least-square estimation of a comb filter delay
This paper focuses on the extraction of the excitation point location on a guitar string by an iterative estimation of the structural parameters of the spectral envelope. We propose a general method to estimate the plucking point location, working into two stages: starting from a measure related to the autocorrelation of the signal as a first approximation, a weighted least-square estimation is used to refine a FIR comb filter delay value to better fit the measured spectral envelope. This method is based on the fact that, in a simple digital physical model of a plucked-string instrument, the resonant modes translate into an all-pole structure while the initial conditions (a triangular shape for the string and a zero-velocity at all points) result in a FIR comb filter structure.
Download Vocal synthesis and graphical representation of the phonetic gestures underlying guitar timbre description
The guitar is an instrument that gives the player great control over timbre. Different plucking techniques involve varying the finger position along the string, the inclination between the finger and the string, the inclination between the hand and the string and the degree of relaxation of the plucking finger. Guitarists perceive subtle variations of these parameters and they have developed a very rich vocabulary to describe the brightness, the colour, the shape and the texture of the sounds they produce on their instrument. Dark, bright, chocolatey, transparent, muddy, wooly, glassy, buttery, and metallic are just a few of those adjectives. The aim of this research is to conceive a computer tool producing the synthesis of the vocal imitation as well as the graphical representation of phonetic gestures underlying the description of the timbre of the classical guitar, as a function of the instrumental gesture parameters (mainly the plucking angle and distance from the bridge) and based on perceptual analogies between guitar and speech sounds. Similarly to the traditional teaching of tabla which uses onomatopeia to designate the different strokes, vocal imitation of guitar timbres could provide a common language to guitar performers, complementary to the mental imagery they commonly use to communicate about timbre, in a pedagogical context for example.
Download An Interdisciplinary Approach to Audio Effect Classification
The aim of this paper is to propose an interdisciplinary classification of digital audio effects to facilitate communication and collaborations between DSP programmers, sound engineers, composers, performers and musicologists. After reviewing classifications reflecting technological, technical and perceptual points of view, we introduce a transverse classification to link disciplinespecific classifications into a single network containing various layers of descriptors, ranging from low-level features to high-level features. Simple tools using the interdisciplinary classification are introduced to facilitate the navigation between effects, underlying techniques, perceptual attributes and semantic descriptors. Finally, concluding remarks on implications for teaching purposes and for the development of audio effects user interfaces based on perceptual features rather than technical parameters are presented.