However, you might not be familiar with "IR repeating." IR repeating allows you to control devices that are not with in the direct line of sight of your remote control. This kind of a system is commonly used in distributed audio/ video systems where the source components are centrally located, or when you wish to control your source devices remotely from an entirely different location. Some plasmas are better shielded than others. How come you need to buy "special" IR passing splitters when using this product? The special thing about IR passing splitters (eg ChannelPlus branded splitters) is that they allow voltage to pass in both directions. Standard splitters, with their internal diode, only allow voltage to pass up the splitter.