Design and Analysis of a Modified Kantele with Increased Loudness

The kantele, an ancient plucked string instrument, belongs to the family of zithers, and it is still used in traditional folk music in Finland, Northwest Russia, and the Baltic countries. Design rules for making the kantele louder are proposed and confirming analysis results are presented. A description of the main characteristics of the traditional design of the kantele is given, so that it supports the presentation of the design rules and analysis results. The design rules to make a plucked string instrument louder are (I) increase the string tension, (II) increase the radiation surface, and (III) isolate the top plate from the sound-box with an air gap. Rules (I) and (II) are almost self evident, for musical acousticians. Rule (III) on the other hand is more unique, since it enables a freely vibrating top plate. The design rules are confirmed by comparing the traditional design with the new one, through several methodological aspects. Results from the analysis are drawn from both analytical treatments and acoustical measurements. The effect that the new design has on the instrument’s dynamic range and perception is investigated through a playability test with several professional kantele players. Results from two listening tests are presented that support the assumption of an increase in loudness for the new kantele design. Loud plucks of the modified design are, on the average, perceived as 3 dB louder than in the traditional design. The design ideas are also applicable to other string instruments.