LG PZ550 50″ 3D Plasma HDTV Chris Heinonen and Stephen Hornbrook November 28, 2011 To follow up my review of the passive 3D LCD LG TV, LG sent me their 50" PZ550 3D Plasma HDTV to check out. This was a great opportunity for me to compare both the active shutter and passive approach to 3D from the same manufacturer. HDTV