1. A device for postprocessing spectral values based on a first transformation algorithm for converting an audio signal into a spectral representation, comprising: a provider for providing a sequence of blocks of the spectral values representing a sequence of blocks of samples of the audio signal; and a combiner for weightedly adding spectral values of the sequence of blocks of spectral values in order to acquire a sequence of blocks of postprocessed spectral values, wherein the combiner is implemented to use, for the calculation of a postprocessed spectral value for a frequency band and a time duration, a spectral value of the sequence of blocks for the frequency band and the time duration, and a spectral value for another frequency band or another time duration, and wherein the combiner is implemented to use such weighting factors when weightedly adding, that the postprocessed spectral values are an approximation to spectral values as they are acquired by a second transformation algorithm for converting the audio signal into a spectral representation, wherein the second transformation algorithm is different from the first transformation algorithm.