Recent works on delay systems have seen the emergence of a new control structure based on delayed actions, including an auto-regressive term carrying on the control variable, with the purpose of achieving a partial pole placement in closed loop for linear time-invariant systems of finite dimension. The ensuing controllers, called quasipolynomial-based controllers, correspond to some output feedback control laws with constant parameters. This specific feature has a limited number of degrees of freedom, limiting the potential performances in closed loop. To overcome this issue, the original quasipolynomial-based controller is enhanced by using dynamical parameters, allowing to increase the number of degrees of freedom available for the controller’s design. It turns out that the use of dynamical parameters corresponds to linear filtered terms in the control law of the original one. To emphasize the benefits brought by such a controller, the active vibration damping problem is addressed for a flexible mechanical structure equipped with a collocated pair of piezoelectric sensor and actuator.