Dynamic range compression is a nonlinear audio effect that reduces the dynamic range of a signal and is frequently used as part of the process of mixing multi-track audio recordings. A system for automatically setting the parameters of multiple dynamic range compressors (one acting on each track of the multi-track mix) is described. The perceptual signal features loudness and loudness range are used to cross-adaptively control each compressor. The system is fully autonomous and includes six different modes of operation. These were compared and evaluated against a mix in which compressor settings were chosen by an expert audio mix engineer. Clear preferences were established for the different modes of operation, and it was found that the autonomous system was capable of producing audio mixes of approximately the same subjective quality as those produced by the expert engineer.