Method as well as apparatus for DS casting using a multi-stage thermal baffle disposed proximate a lower end of a DS casting furnace. Such an HSA may include a single connector having a mating interface and a fastener extending from a surface of the connector, a flex circuit attached to the connector, and a gasket seal placed on the upper surface of the connector. An electrolytic solution is impregnated in the separator. Clips may also be utilized to secure the wire in the container. Also, since a Nyquist diagram of the system satisfies required characteristics, a repeatable run-out error may be compensated for without causing instability of the servo system due to use of the peak filter.