An energy signal processing system (10) includes a first shaft assembly (14) rotatable about an azimuth axis (16), and a second shaft assembly (18) coaxially mounted for rotation about the azimuth axis (16). The first shaft assembly (14) defines a zenith plane (20) inclined with respect to the azimuth axis (16). The system (10) includes an energy signal processing element (22) rotatable about a processing element axis (24) that intersects and is generally perpendicular to the azimuth axis (16), as well as a means for rotating the element (22) about the element axis (24) such that: energy signals travelling substantially along a preselected path axis (12) and impinging the energy signal processing element (22) are processed or deflected substantially along the azimuth axis (16); or vice versa; or energy signals generated by the energy signal processing element (22) are directed substantially along the preselected path axis (12).