Solid-borne vibrations and airborne vibrations from a gradient coil unit in an MRI gantry environment are markedly reduced thereby reducing ambient noise occurring due to the vibrations. Support assemblies retain the gradient coil unit in a mechanically-uncoupled or substantially-uncoupled state relative to the magnet by supporting the coil unit at separate positions on the floor (e.g., with anchor bolts rigidly coupling coil support assemblies to the floor). Moreover, the gradient coil unit and at least parts of the support assemblies may be retained in a vacuum space.