Methods for generating complex waveforms, including step functions, impulse functions, and gate pulses are provided, as well as methods for generating modulated waveforms employing a number of known and newly developed modulation formats. The device holder and storage compartment are in the form of a slidable drawer that is concealed within a dashboard when in a closed position and extended from the dashboard when in an open position. The audio processing system comprises a compensator with a transfer function for obtaining at least two compensated signals from the input signals. The combination may be sufficient to flocculate at least some of the suspended particulates in the water component of the waste sludge and sufficient to produce treated waste sludge.