In this paper, several mathematical models that are more realistic representations of mechanical band-pass filters are studied. Such filters can be used in energy scavengers to convert energy from vibration sources into a small amount of electricity. A mechanical band-pass filter is an ensemble of cantilever beams where at the tip of each beam a mass, known as the proof mass, is mounted. A beam with a proof mass at its tip is called a beam-mass system. By studying a variety of models representing the filter dynamics, it will be unraveled to what extent fabrication errors in beam-mass systems of a filter and/or the coupling of such systems can alter the band-pass behavior of a fabricated filter.