The invention is a method for manufacturing an optical module where on forms a groove in a substrate for positioning a component such as an optical component. The method includes: removing fly ash from a flue gas stream utilizing a particle collector ; contacting the flue gas stream with an alkaline reagent in a wet scrubber ; discharging a purge liquid from the wet scrubber ; and, combining at least a portion of the purge liquid with at least a portion of fly ash circulating within a dry circulating fluid bed scrubber to form moistened fly ash. The front face has a variable stiffness so as to create a variable Coefficient of Restitution across the face, therein normalizing the hitting area over a greater portion of the face. This enables concurrent playback of multi-track media-based trading cards, providing entertainment and collectible value for users. This minimizes the settling periods of the input signals with respect to the select signals.