A method for rendering L1 channel-based input audio signals (w1 1) to L2 loudspeaker channels, where L1 is different from L2, the method comprising steps of: determining a mix type of the L1 input audio signals, wherein the mix type specifies a geometry for reproducing the input audio signals; performing a first delay and gain compensation on the L1 input audio signals according to the determined mix type, wherein a delay and gain compensated input audio signal with L1 channels and with a defined mix type is obtained; applying a mixing matrix to the delay and gain compensated input audio signal Z with L1 audio channels, wherein a remixed audio signal for L2 audio channels is obtained; performing a second delay and gain compensation on the remixed audio signal for L2 audio channels, wherein L2 loudspeaker channels (w2 2) are obtained, characterized in that the mixing matrix G is energy preserving, and obtained by: performing a singular value decomposition on a conventionally derived mixing matrix Ĝ according to Ĝ = U S V T, wherein and are orthogonal matrices and S ∈ R L2xL1 is a singularity matrix, forming (s713, S714) a quantized singularity matrix Ŝ having s m diagonal elements, corresponding to diagonal elements of S greater than a threshold, set to one, and remaining diagonal elements, corresponding to diagonal elements of S less than the threshold, set to zero, determining a scaling factor a chosen for energy preservation, and determining a mixing matrix G according to G = a U Ŝ V T. determining a mix type of the L1 input audio signals, wherein the mix type specifies a geometry for reproducing the input audio signals; performing a first delay and gain compensation on the L1 input audio signals according to the determined mix type, wherein a delay and gain compensated input audio signal with L1 channels and with a defined mix type is obtained; applying a mixing matrix to the delay and gain compensated input audio signal Z with L1 audio channels, wherein a remixed audio signal for L2 audio channels is obtained; performing a second delay and gain compensation on the remixed audio signal for L2 audio channels, wherein L2 loudspeaker channels (w2 2) are obtained, characterized in that the mixing matrix G is energy preserving, and obtained by: performing a singular value decomposition on a conventionally derived mixing matrix Ĝ according to Ĝ = U S V T, wherein and are orthogonal matrices and S ∈ R L2xL1 is a singularity matrix, forming (s713, S714) a quantized singularity matrix Ŝ having s m diagonal elements, corresponding to diagonal elements of S greater than a threshold, set to one, and remaining diagonal elements, corresponding to diagonal elements of S less than the threshold, set to zero, determining a scaling factor a chosen for energy preservation, and determining a mixing matrix G according to G = a U Ŝ V T. performing a singular value decomposition on a conventionally derived mixing matrix Ĝ according to Ĝ = U S V T, wherein and are orthogonal matrices and S ∈ R L2xL1 is a singularity matrix, forming (s713, S714) a quantized singularity matrix Ŝ having s m diagonal elements, corresponding to diagonal elements of S greater than a threshold, set to one, and remaining diagonal elements, corresponding to diagonal elements of S less than the threshold, set to zero, determining a scaling factor a chosen for energy preservation, and determining a mixing matrix G according to G = a U Ŝ V T.