voltage a is passed to the electronic musical effect generator 24 whose output is connected to amplifier 26 which is connected to speaker 28 strain measurement devices in accordance with the present invention are installed at various sites along the guitar neck 32 to measure slight bends in the neck in a plurality of axes a strain gauge assembly 20 on the guitar neck generates a control signal voltage b on line 34 proportional to the flexure in the guitar neck this control signal voltage b is passed to an input of a signal conditioning circuit 22 for filtering and normalization see fig5 for details a separate strain and pressure measurement assembly 39 is installed on the face of a guitar pick 18 structural deflections in the guitar pick 18 generate another ensemble of control signal voltages c on lines 49 that is passed to another input of the signal conditioning circuit for filtering and normalization the output d of the signal conditioning circuit 22 is the final ensemble of conditioned signal voltages on line 52 that accurately represents the flexural condition of the guitar and guitar pick these conditioned control signal voltages are applied on line 52 as an.