Abstract: A method of generating a composite audio signal, comprising: receiving an input audio signal; performing a first comparison, wherein at least a first portion of the input audio signal is compared with at least a portion of one or more stored audio signals; selecting at least a first portion of a stored audio signal based on a result of the first comparison; performing a second comparison, wherein at least a second portion of the input audio signal is compared with at least a portion of one or more stored audio signals; selecting at least a second portion of a stored audio signal based on a result of the second comparison; and generating the composite audio signal using at least the selected first and second portions of a stored audio signal.