A method of noise filtering on a locomotive includes converting sounds received by one or more transducer at first and second period of times into first and second electric signals and comparing a value of a signal that varies with operation, movement, or both of the locomotive to a reference value. When the signal value is one of less than or greater than the reference value during the first period of time, a controller stores a first unfiltered digitized version of the first sound in a memory. When the signal value is the other of less than or greater than the reference value during the second period of time, the controller stores in the memory a second, filtered digitized version of the second sound that is filtered in a frequency spectrum associated with the second sound.