An electromechanical control unit (12) for a musical instru­ment having keypad and/or touch pad areas (102) for con­trolling a signal processing unit, wherein the control unit (12) includes a surface element (101), whereby settings and val­ues of said signal processing unit that can be changed by the user are controlled by touching of the surface element, which surface element has keypad and/or touch areas (102) provided with fixed and/or alternating symbols whereby changeable parameter values of the signal processing unit are controlled by touching and/or by gliding on said symbol with finger(s) or some other means, and wherein in order to adjust the parameter values that can be changed by the user the control unit consists of a thin and elastic layered structure whereby touching it generates there between the electrode surfaces a charge or voltage or capacitance change the place and/or amplitude of which is calculated with a microprocessor or alike, and based on this informa­tion said changeable parameter values are changed.