The wave equation for stiff strings and piano tuning

We study the wave equation for a string with stiffness. We solve the equation and provide a uniqueness theorem with suitable boundary conditions. For a pinned string we compute the spectrum, which is slightly inharmonic. Therefore, the widespread scale of 12 equal divisions of the just octave is not...

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Detalles Bibliográficos
Autores: Gràcia Sabaté, Francesc Xavier|||0000-0003-1006-4086, Sanz Perela, Tomás|||0000-0002-1210-1111
Tipo de recurso: artículo
Fecha de publicación:2017
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/101752
Acceso en línea:https://hdl.handle.net/2117/101752
Access Level:acceso abierto
Palabra clave:Differential equations, Partial
wave equation
vibrating string
stiffness
inharmonic spectrum
musical scale
dissonance
Equacions en derivades parcials
Equacions diferencials hiperbòliques
Classificació AMS::35 Partial differential equations::35G General higher-order equations and systems
Classificació AMS::35 Partial differential equations::35L Partial differential equations of hyperbolic type
Àrees temàtiques de la UPC::Matemàtiques i estadística::Equacions diferencials i integrals::Equacions en derivades parcials
Àrees temàtiques de la UPC::Matemàtiques i estadística::Equacions diferencials i integrals::Equacions en diferències
Descripción
Sumario:We study the wave equation for a string with stiffness. We solve the equation and provide a uniqueness theorem with suitable boundary conditions. For a pinned string we compute the spectrum, which is slightly inharmonic. Therefore, the widespread scale of 12 equal divisions of the just octave is not the best choice to tune instruments like the piano. Basing on the theory of dissonance, we provide a way to tune the piano in order to improve its consonance. A good solution is obtained by tuning a note and its fifth by minimizing their beats.