Digital musical instruments (DMI) can make musical practice accessible to non-trained persons or to persons with limitations related to their age, gender or musical experience. The present study explores accessibility and participation in a sample of 266 individuals using a device named MotionComposer, a digital instrument based on motion capture. By experimenting with this device during four minutes in two different environments (one causal, the other one more aprioristically determined), we study the kind of participant interaction that takes place. Results show that MotionComposer allows for a statistically significant similar interaction in people of different ages and genders and with different disabilities. However, there are two exceptions that can be accounted for in connection with the causality-randomness of the two environments where the experimentation takes place.