Frequency-domain audio decoder supporting transform length switching, comprising a frequency-domain coefficient extractor configured to extract frequency-domain coefficients of frames of an audio signal from a data stream; a scale factor extractor configured to extract scale factors from the data stream; an inverse transformer configured to subject the frequency-domain coefficients of the frames, scaled according to the scale factors, to inverse transformation to obtain time-domain portions of the audio signal; a combiner configured to combine the time-domain portions to obtain the audio signal, wherein the inverse transformer is responsive to a signalization within the frames of the audio signal so as to, depending on the signalization, form one transform by sequentially arranging the frequency-domain coefficients of a respective frame, scaled according to the scale factors, in a non-de-interleaved manner and subject the one transform to an inverse transformation of a first transform length, or form more than one transform by de-interleaving the frequency-domain coefficients of the respective frame, scaled according to the scale factors, and subject each of the more than one transforms to an inverse transformation of a second transform length, shorter than the first transform length, characterized in that the frequency-domain coefficient extractor and the scale factor extractor operate independent from the signalization, and the inverse transformer is configured to perform inverse temporal noise shaping filtering onto a sequence of N coefficients irrespective of the signalization by applying a filter a transfer function of which is set according to TNS coefficients onto the sequence of N coefficients, with in the formation of the one transform, applying the inverse temporal noise shaping filtering using the frequency-domain coefficients sequentially arranged in a non-de-interleaved manner as the sequence of N coefficients, and in the formation of the more than one transforms, applying the inverse temporal noise shaping filtering on the frequency-domain coefficients using the frequency-domain coefficients sequentially arranged in a de-interleaved manner according to which the more than one transforms are concatenated spectrally as the sequence of N coefficients. form one transform by sequentially arranging the frequency-domain coefficients of a respective frame, scaled according to the scale factors, in a non-de-interleaved manner and subject the one transform to an inverse transformation of a first transform length, or form more than one transform by de-interleaving the frequency-domain coefficients of the respective frame, scaled according to the scale factors, and subject each of the more than one transforms to an inverse transformation of a second transform length, shorter than the first transform length, in the formation of the one transform, applying the inverse temporal noise shaping filtering using the frequency-domain coefficients sequentially arranged in a non-de-interleaved manner as the sequence of N coefficients, and in the formation of the more than one transforms, applying the inverse temporal noise shaping filtering on the frequency-domain coefficients using the frequency-domain coefficients sequentially arranged in a de-interleaved manner according to which the more than one transforms are concatenated spectrally as the sequence of N coefficients.