Downmixer, audio encoder, method and computer program applying a phase value to a magnitude value

A downmixer for providing a downmix signal on the basis of a plurality of input signals is configured to determine a magnitude value of a spectral domain value of the downmix signal on the basis of a loudness information of the input signals. The downmixer is configured to determine a phase value of the spectral domain value of the downmix signal and the downmixer is configured to apply the phase value in order to obtain a complex valued number representation of the spectral domain value of the downmix signal on the basis of the magnitude value of the spectral domain value of the downmix signal. An audio encoder uses such a downmixer. A method for downmixing and a computer program are also described.