Abstract: The present invention provides signal processing method and apparatus for audio special effect processing on an input signal. The signal processing system of the invention eliminates the need for FFT and inverse FFT operations from an audio signal decoding system by providing au audio special effect processing routine before a frequency-to-time conversion. The audio special effect processing routine may perform equalization and/or base boost operations. After an input signal is processed by the, the modified input signal is converted to a time-domain signal by a frequency-to-time conversion unit so that audible sound may be generated based on the time-domain signal. The frequency-to-time conversion unit may comprise an MDCT (modified discrete cosine transform) routine and comprise a synthesizer filter.