Hi, I'm building a loudspeaker and I want to support the Woofer and front panel from a steel strut, which is fixed to the sub-woofer box below. Please see the drawing attached. The strut is made from 20mm x 20mm steel bar. I would like help to calculate the resonance frequency of the woofer and panel hanging on that strut, as I'd like to make sure it is above the working range of the woofer (to avoid resonance). To do this I assume we need the physical dimensions (in the drawing), the weight of the item on the strut and the stiffness of the spring (the steel). I don't know how to put that all together though! Units are mm. Some general info for steel is available by searching goggle, I didn't provide it here as I don't know exactly the info you need. Young's modulus maybe? Thanks!