A disk device for improving a SIN ratio is provided with a spindle motor control substrate 10 arranged below a tray 3 via a buffer material and a medium substrate 12 arranged at a position different from the spindle motor control substrate 10 below the tray 3. An adjustable furrow closing assembly enhances upper seed groove coverage and closure with soil resulting in sustained relative humidity levels and optimum seed-to-soil contact for faster seed germination. Furthermore, a point or area in a design space corresponding to arbitrary design parameters corresponding to a point or area specified by a user in the displayed feasible region is displayed. A hose may be moved freely around the yard, being guided by the retractable hose guide, thus avoiding damage either to the hose or to the landscaping. Any lattice mismatch between the accommodating buffer layer and the underlying silicon substrate is taken care of by the amorphous interface layer.