Each of the monitors comes with a dual input Amplifier when they were bought from Visualogic, I am not sure how they are supplied these days as I purchased mine 2 years ago. I mounted one dvd player under the rear seat and the other input is from the head unit. I put the kids on one program with wireless head phones, and enjoy what I want from the head unit. This has worked well for my situation, including the interfaces for the bose speakers and the steering wheel controls. overall I am pleased with the outcome.
You should know kure beach when you see it....