Audio Systems: Infinity speaker compatibility, sony xplod cd player, infinity speakers


Question
I want to put a Sony Xplod CD player in my 1990 Caravan. In the Sony manual, it says not to connect it to amplified speakers, (I guess like the existing Infinity speakers?)
What will happen if I connect them?
Can I just remove the power going to the speaker amplifiers?
I notice at each speaker the leads split, going both to the speaker itself, (voice coil) and also (I assume) to the amp input. (Which then seems to come out and go to a second voice coil...?)
Would I have to isolate the amp input from my signal and just use the direct-to-the-speaker connection?
Here's the kicker: I also want to leave the original Infinity stereo and be able to switch the speakers from one to the other with relays.  

Answer
Hi Darren!
It is recommended not to connect the radio to amplified speakers since the amp input is too high impedance for the output ic, to solve that you can use an adaptor named High to low apater wich converts speaker level to line level(check here:http://www.installer.com/hilo/), also remeber that some sony headunits have a beep sound that goes out trough the speakers and it can be quite loud in an amplified sytem.
NOTE:The beep will not sound trough the RCA outputs of the radio if it is equipped with them.