Elejalde-García M., Macho-Stadler E., Llanos-Vázquez R.

The control techniques of buttons and bellows have great importance for the sound production of the accordion. The acoustical knowledge of these techniques contributes to do them more effective for accordion players. Accordion player can complement the basic use of the bellows (to vary the dynamics) and of the buttons (to get the diverse ways of articulation) with other expressive resources. The practical use of these techniques in accordion playing is varied. Some of these possibilities are based in the use of the different types of attack achieved by the combination of bellows and buttons. Other possibilities use the fact that the bellows is not the only source of the variation in the dynamics of the accordion: the player can obtain small but perceptible variations of the sonority modifying the button pulsation. In this work, we study the role of buttons and bellows in the sound production of the accordion. We focus on the analysis of the acoustical properties of different attacks and the influence of the button velocity in the attacks. We study how the transient time depends on the attack type and the behaviour of the different harmonics during the transient time. We also study the dependence of the attacks on the dynamics, the pitch and the register.