A method and apparatus for detecting mechanical interaction in a disk drive system which includes one or more rotatable disks, one or more radially movable heads cooperating with the disks for transfer of data there between, and a carriage for supporting the heads, has a waveguide, coupled to the carriage, for conducting acoustic stress waves corresponding to the mechanical interaction. The acoustic stress waves conducted from the carriage are then preamplified and selectively filtered before being fed to a signal processor and waveform analyzer. In such a manner, specific frequencies or ranges of frequencies of interest, each of which correspond to a particular mechanical interaction are analyzed by the waveform analyzer.