Inharmonicity of two-tones in contra octave of upright piano


  • Zoran Milivojevic
  • Milena Rajkovic
  • Dragan Milosavljevic



fundamental frequency, harmonic, inharmonic, piano


The paper describes inharmonicity of musical instruments with strings. In the first part an algorithm for determination of coefficient of inharmonicity is shown, as well as algorithm for inharmonicity estimation and estimation of mean aliquote error of two-tone. In the second part paper shows results of algorithm’s application in signal processing of tones in contra octave of upright piano “August Förster” manufactured in the year 1970.  The results are given in graphics and in tables. An estimation of inharmonicity and medium aliquote error is given by comparative analysis made with Steinway pianos and Nordiska 1 and Straud upright pianos.


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How to Cite

Milivojevic, Z., Rajkovic, M., & Milosavljevic, D. (2023). Inharmonicity of two-tones in contra octave of upright piano. South Florida Journal of Development, 4(5), 1946–1956.