Car Stereos: Dual XR4110 in a boat, external switch, 12 volt

Question
Hello, I have an Audiovox Marine radio I'd like to replace in my ski boat. I purchased a Dual XR4110 and am trying to match the wires. I have only one power source wire (identified only as +12 volts) so I'm struggling to decide where to connect the XR4110 red (accessory power) and XR4110 yellow (memory power) wires? Should I connect both red and yellow to the single source? Or should I leave the yellow unconnected knowing I will lose memory pre-sets, etc? Thanks.

Answer
Hi Tom,

Sorry about the delay in answering your question.

If you leave the yellow wire disconnected, the head unit won't work at all.  A Dual head unit requires voltage on both the yellow and the red wire before it can be switched on.  In your case, the easiest option is to just connect both wires to the single 12-volt source wire.

You'll only need to separate the wires if you want to be able to switch the head unit on and off through an external switch.  If you want the radio to work with the boat's key switch, or a toggle switch on the control panel, then the yellow wire should be connected directly to the main power wire, while the red wire is connected through the switch.  One advantage to doing this is that the head unit may use less power while it's shut down, if the red wire's not powered.  This might help the battery's charge last longer when you're not using the audio system.

Hope this helps!

Brian