A vibration monitoring system includes a plurality of encoders and an analyzer. The encoders are configured to generate multiple pulse train signals for multiple wheels. Each encoder is coupled to a respective one of the multiple wheels and generates a single one of the pulse train signals. The analyzer is coupled to the encoders and is configured to generate multiple pulse per revolution signals and multiple angular velocity signals for the wheels in response to the pulse train signals. Each pulse per revolution signal conveys a single pulse per rotation of the respective wheel. The analyzer is further configured to generate an input phasor array representative of the pulse per revolution signals, generate a response phasor array in response to the angular velocity signals for the wheels, and generate a report that identifies at least one vibrating wheel in response to the input phasor array and the response phasor array.