Apparatus and method for spatial audio object coding employing hidden objects for signal mixture manipulation

An apparatus for encoding one or more audio objects to obtain an encoded signal is provided. The apparatus comprises a downmixer (110) for downmixing the one or more audio objects to obtain one or more unprocessed downmix signals. Moreover, the apparatus comprises a processing module (120) for processing the one or more unprocessed downmix signals to obtain one or more processed downmix signals. Furthermore, the apparatus comprises a signal calculator (130) for calculating one or more additional signals, wherein the signal calculator (130) is configured to calculate each of the one or more additional signals based on a difference between one of the one or more processed downmix signals and one of the one or more unprocessed downmix signals. Moreover, the apparatus comprises an object information generator (140) for generating parametric audio object information for the one or more audio objects and additional parametric information for the additional signal. Furthermore, the apparatus comprises an output interface (150) for outputting the encoded signal, the encoded signal comprising the parametric audio object information for the one or more audio objects and the additional parametric information for the one or more additional signals. Moreover, a corresponding apparatus for decoding is provided.