Abstract: A digital audio synthesizer is provided that includes the following: an input memory, a computer, a combiner, and an adder. The combiner is set up to calculate an auxiliary digital data set by taking an active set of estimated digital data divided by a window function on each time window. The adder is set up to add the active set of estimated digital data multiplied by the window function having the preceding value from an accumulated total. The digital audio synthesizer also includes an extrapolator that is set up to calculate the draft digital data set for an active window from the auxiliary digital data set for the preceding window, and the auxiliary digital data set is selectively multiplied by the square of the window function.

Abstract: The invention relates to a digital audio synthesizer that includes: an input memory for receiving a sequence of digital data representing the amplitude spectrum of an audio signal over consecutive and overlapping time windows; a computer (120) that is set up to receive, as an input, a draft digital data set for a active window including amplitude-extrapolated data at the start of a window and zero values for the rest of the window, and to establish, as a response, a digital representation of the discrete complex Fourier transform for said set; a dialer (130) that is set up to combine the amplitude spectrum input, corresponding to the active window in question, with the digital representation predetermined by the computer, and to call the computer (120) with the resulting data in order to establish a digital representation of the corresponding complex inverse discrete Fourier transform that provides a set of estimated digital data related to the active window in question; and an adder (140) for selectively acc