The new single crystals offered here possess exceptional properties and are poised to revolutionize piezoelectric materials applications. In addition to strain levels exceeding 1% (usable strain: 0.5% at 35 kV/cm), these crystals exhibit five times the strain energy density of conventional piezoceramics. Thus, unlike piezoceramic actuators that employ strain magnification schemes, single crystal actuators can deliver higher strain levels without sacrificing generative force. The high electromechanical coupling of the proposed crystals (>90%) increases transducer bandwidth, resulting in greater sensitivity and acoustic power. In addition, low strain hysteresis results in improved high power efficiency, and lower acoustic impedance than piezoceramics allowing for easier matching to air or water. High coupling also leads to dramatic improvement in passive vibration damping.