I've got to be honest I've been using wireless mic's at my high school for four years with a lot of luck but knowing really nothing about the frequencies they were operating on. Now that I’m moving to another theater and have to expand my system and the more I try to learn about them the more confused I get. I understand the whole DTV transition puts the 700mhz band off limits but I don’t know where to go from there. As a recall, my eight channel sennheiser g2 setup had frequencies operating in both the 300mhz and 500mhz range. I'm located in Los Angeles and I know it varies by market but I have no idea what the whole A block C block thing is about and how you would find out which would be best. I already checked out the sticky wireless mic FAQ and I couldn’t discern a clear answer to this. A link to a tutorial or a simple explanation would be greatly appreciated. Thanks.