The lowest order enclosure panel resonance is associated with a large loss in enclosure
effectiveness at the resonance frequency. Thus the enclosure should be designed so that the
resonance frequencies of its constituent panels are not in the frequency range in which
appreciable sound attenuation is required. Only the lowest order, first few, panel resonances are
of concern here. The panels may be designed such that their resonance frequencies are higher
than or lower than the frequency range in which appreciable sound attenuation is required.
Additionally, the panels should be well damped or "dead" which generally requires treatment
with some form of visco-elastic damping material.