Unshielded speakers will not have any effect on a plasma, LCD, SXRD, LCoS, or any other non CRT techonology. The reason that unshielded speakers have an effect on CRTs is that CRT set work by firing a beam of electrons at phosphers bound to a glass substrate. When the electrons hit the phosphers the enter a charged state and glow. Electrons, as we all learned in high school physics, havea negative charge. The magnets in an unshielded speaker are free to attract/repell the electron beam in the CRT thereby "bending" the ray. This excites the wrong pixels and messes up the picture. As no other TV light engines require thae electron beam to create pictures, the magnets in speakers have no effect.