take the unit out, put a MM from one terminal to other- if 6 ohms ish or 8.. then the coil is intact, and look twds one of the few crossover components. bit of basic trial and error should find the culprit. then, if up and running and the vibration still there, its likely either A) the alu cylinder which slides over the centre bit is rubbing, and can be fixed by VERY carefully inserting say a round of stiff paper easing any gubbins. or B) the vol may have been up high (?), or general useage, and this alu has warped and been damaged (and/or the coil itself on its outside), irrepairably. Im afraid its likely B, small chance A. but hope for you I may be wrong.
check with bourney 1st though, as the sorcerors unit may not be the one Im thinking of.
