The present disclosure relates to a system for a material reducing machine that allows a reducing rotor to be selectively configurable in a plurality of different reducing configurations. The different reducing configurations in which the reducing rotor can be configured can include reducing configurations having reducers located at different positions, reducing configurations having different reducer densities (e.g., different overall densities and different regionalized densities), reducer configurations having different reducer counts, reducer configurations having different reducer patterns, and reducer configurations having different lay-outs.