The quality of exhaust sound has become one of the important factors in the motorcycle market. Therefore both an efficient sound quality evaluation method and technology to achieve ideal sound quality have become necessary. Sound quality evaluation has generally been performed by trial and error through repeated modification of exhaust silencer construction until the desired quality was obtained. This process, however, usually involved painstaking work and long times. In order to solve such problems we established an objective auditory evaluation method. We also applied principal component analysis to analyse the result of the 'Semantic Differential Method (SD method)' for determining the affecting elements. Through this analysis system, 'powerful sound' caused by relatively higher contents of the low frequency range, and 'crispy sound' caused by a cyclic sound pattern were determined to be desirable sound patterns for American type motorcycles. We established a system for approximate frequency distribution characteristic estimation for simply constructed exhaust silencers by introducing a numerical computation method (Finite Element Method (FEM)) and Boundary Element Method (BEM) to estimate the sound when component elements of the exhaust silencer were modified.
Evaluation method of exhaust sound quality of motorcycle
Methode zur Ermittlung der Charakteristik der Auspuffgeräusche von Motorrädern
1997
6 Seiten, 8 Bilder, 1 Tabelle
Conference paper
English