a musical device controller and system that includes an electric guitar having strings and a pick - up that produces an electrical music signal from vibrations of the strings , a musical effect generator that receives the electrical music signal from the guitar and alters the musical signal to produce a musical effect , a guitar pick for striking the strings to cause the vibrations , and a force sensing device mounted on the guitar pick . the force sensing device has a pair of electrical leads connected to the musical effect generator , and a pressure sensitive material that is formed of a semiconductor material having microprotrusions or a pressure sensitive ink . the electrical leads are in contact with the pressure sensitive material such that electrical resistance between the pair of leads incrementally and repeatably decreases as a force applied to the force sensing device incrementally increases . the musical effect generator is responsive to , and varies the musical effect according to , the resistance between the pair of leads .