A method of generating electrical signal waveforms. A generator includes a digital processing circuit, a memory circuit in communication with the digital processing circuit defining a lookup table, a digital synthesis circuit in communication with the digital processing circuit and the memory circuit, and a digital-to-analog converter (DAC) circuit. The method includes generating a first and second digital electrical signal waveforms, combining the first and second waveforms to form a combined waveform, modifying the combined waveform to form a modified waveform The peak amplitude of the modified waveform does not exceed a predetermined amplitude value. The method includes generating a second waveform that is a function of the first waveform. The method includes modifying a frequency of the first waveform to form a frequency modified first waveform and combining the frequency modified first and second waveforms to form a combined waveform.
