This paper investigates experimentally and analytically the effect of Active Strain Energy Tuning (ASET) on low actuator fraction Shape-Memory Alloy (SMA) hybrid composite laminates. It shows that in these materials ASET results in reductions in resonance frequencies during actuation, in contrast to the behaviour observed in higher actuator fraction laminates. A simple analytical model is presented to interpret the results. This shows that in general terms there is no difference in the mechanism of frequency shifts in low and high actuator fraction materials. The reductions in natural frequency observed in low actuator fraction laminates occur simply because the force developed by the actuators is too small to overcome matrix thermal stresses; in contrast to the control authority available in composites containing higher actuator fractions.