Abstract: Distortion modeling produces distortion models for use by a distortion synthesizer to synthesize the harmonic distortion effects of audio distortion devices. A sinusoidal waveform is distorted by an audio distortion device and analyzed using a Fourier transform to produce a distortion model comprising harmonic amplitude and phase parameters. A phase correction process compensates for phase shifts induced by the audio distortion device. The distortion synthesizer uses a distortion function that distorts a digital audio signal according to the distortion model. The distortion model can be modified to alter the distortion effect and can be stored in a data-storage device for later retrieval. A frequency bandsplitter and signal mixer allow the distortion effect to be applied only to the low frequency content of the digital audio signal, thus providing spectral headroom to suppress the production of aliasing noise.

Abstract: A marble race toy including a modular track that is assembled by the user from channel components into any desired configuration. An infrastructure is utilized to support the desired track layout. An infrastructure is utilized to support the desired track layout. Affixing elements are used to fix dowel rods of the infrastructure in place, and thereby support the modular components of the track. An elevator with an endless conveyor raises the marbles to a start position of the track, and retrieves them from an end position of the track.