The polytitanate phase and CaTiO3 were identified as the residual secondary phases in calcined and sintered samples, whereby strategies for their removal included defined addition of excess A-site ions and quenching. A major improvement in the piezoelectric coefficient has been obtained after the removal of the polytitanate secondary phase, demonstrating the importance of the actual A/B stoichiometric ratio within the samples. In addition, these experiments underlined the significance of point defects, which can inhibit domain wall movement and deteriorate the electromechanical strain.