A system for reducing compressor noise includes a rotor having a plurality of blades. The blades have a nominal geometry characterized by a blade parameter. At least some of the blades are mistuned, such that they differ from the nominal geometry by greater than a manufacturing tolerance in the blade parameter. The blades produce shock waves at a blade passing frequency, and the mistuned blades shift acoustic energy away from the blade passing frequency to multiple lower amplitude tones at other frequencies. The system is configurable to be deployed with an inlet silencer that preferentially absorbs acoustic energy at some of the shifted frequencies.