1. An audio signal encoder for providing a bitstream representation on the basis of a plurality of audio object signals, the audio signal encoder comprising: a downmixer configured to provide a downmix signal on the basis of the audio object signals and in dependence on downmix parameters describing contributions of the audio object signals to one or more channels of the downmix signal; and a parameter provider configured to provide a common inter-object-correlation bitstream parameter value associated with a plurality of pairs of related audio object signals, and to also provide a bitstream signaling parameter indicating that the common inter-object-correlation bitstream parameter value is provided instead of a plurality of individual inter-object-correlation bitstream parameter values; wherein the parameter provider is configured to also provide an object relationship information describing whether two audio objects are related to each other; and a bitstream formatter configured to provide a bitstream comprising a representation of the downmix signal, a representation of the common inter-object-correlation bitstream parameter value and the bitstream signaling parameter.