1. A method for rendering a Higher-Order Ambisonics (HOA) representation of a sound or sound field, comprising: decoding coefficients of the HOA sound field representation; determining a mix matrix G based on L speakers and positions of a spherical modelling grid related to a HOA order N; determining a mode matrix {tilde over (Ψ)} based on the spherical modelling grid and the HOA order N; rendering the coefficients of the HOA sound field representation from a frequency domain to a spatial domain based on a smoothed decode matrix {tilde over (D)}; wherein a compact singular value decomposition of a product of the mode matrix {tilde over (Ψ)} with a Hermitian transpose of the mix matrix G is determined based on U S V H ={tilde over (Ψ)}G H , wherein U,V are based on Unitary matrices and S is based on a diagonal matrix with singular value elements, and a first decode matrix ({circumflex over (D)}) is determined based on the matrices U,V based on {circumflex over (D)}=V Ŝ U H , wherein Ŝ is a truncated compact singular value decomposition matrix that is either an identity matrix or a modified diagonal matrix, the modified diagonal matrix determined based on the diagonal matrix with first and second singular value elements, wherein at least a first singular value element that is larger or equal than a threshold is equal to ones, and at least a second singular value element that is smaller than the threshold is equal to zero, and wherein the smoothed decode matrix {tilde over (D)} is determined based on smoothing and scaling of the first decode matrix {circumflex over (D)} with smoothing coefficients.