An electro-magnetic transducer assembly includes a first component. The first component includes at least one magnet, and optionally a first attachment mechanism for attaching the first component to a vibrating structure. A coil assembly includes a second attachment mechanism for removably attaching the coil assembly to the first component. The coil assembly further includes at least one coil that produces a signal representative of the vibration of the at least one magnet. An output port provides the signal.