Method and apparatus for processing audio signals

An apparatus for processing an audio signal, which is used for performing binaural rendering for multi-audio signals including multi-channel or multi-object signals, the multi-audio signals each including a plurality of subband signals, the apparatus comprising:

• a fast convolution unit configured to perform rendering of direct sound and early reflections sound parts for each subband signal;
• and
• a late reverberation generation unit configured to perform rendering of a late reverberation part for each subband signal,
• wherein the fast convolution unit receives truncated subband filter coefficients for filtering the multi-audio signals, the truncated subband filter coefficients being at least a portion of subband filter coefficients obtained from binaural room impulse response (BRIR) filter coefficients for binaural filtering of the multi-audio signals, lengths of the truncated subband filter coefficients being determined based on filter order information obtained by at least partially using characteristic information extracted from the corresponding subband filter coefficients, and a length of truncated subband filter coefficients of at least one subband being different from a length of truncated subband filter coefficients of another subband, and
• wherein the fast convolution unit filters each subband signal of the multi-audio signals by using truncated subband filter coefficients corresponding to each subband signal.