Method and apparatus for providing high strength, low frequency tactile sensations using an inertial actuator in a haptic feedback interface device, such as an actuator driving an oscillating inertial mass. A commanded low frequency is modulated or combined with a higher frequency at which the tactile sensations feel stronger, where the resulting signal is used to output a tactile sensation at the higher frequency and convey the commanded low frequency to the user. One embodiment provides higher frequency pulse bursts at the desired low frequency wherein the higher frequency pulse bursts are at or near a resonant frequency of the actuator; other embodiments modulate or otherwise vary the amplitude of the higher frequency signal according to the desired low frequency.