I am adding a sub enclosure I built and was trying to decide where to get my signal leads from. I was curious if the back of the MyGiG unit was like the 6 disc head unit; since I only found pics and diagrams of those. If anyone has a pic of the back of the unit and could post it for me that'd be great.
Thanks!

 

They are almost identical (same connectors and locations) and from all the documentation I've seen, the pin outs are the same as well. The only difference is an addition connector for the GPS antenna to connect to, but that is obviously separate from the main connectors you are talking about. While the pin outs appear to be the same, the one issue I've encountered is that different features may be enabled or disabled based on the vehicle it's installed in. This is handled in the software (firmware). You should also know there are now multiple versions of the firmware 'in the wild' (I've seen five myself) all created and distributed by Harmon Kardon. Different features may also be enabled/disabled as well as bugs fixed or existing based on the version you have.

I've not personally tried to add a sub, but I'd guess that it could be done by connecting to the speaker wires going to any of the speakers (although you have to remember that those are high power and should only be connected to a powered sub or amplifier that is configured to accept that type of power according to the manufacturer's instructions). There is no easily accessible 'Line Out' on the back of the MyGig or 6 Disc Changer for that matter. I believe for the stock Infinity system that includes an Amplifier and Sub, they receive signals from the Amp over the CAN bus and automatically adjust the speaker outputs to 'Line Level' and that feeds the amp directly. There are ways to fake this signal, but then you would have to install an amplifier to power the main speakers as the amplifier in the MyGig would be turned off.

I hope this helps.

 

Thanks skydyvyr!!

That is pretty much what I expected as far as the connectors go for cost driver reasons. In a perfect world manufactures would give us the Line out but I was planning on having to either use an amp with high level inputs (which are apparently harder to find now days) or using a line converter. I was trying to decide weather to use the amp leads like you mentioned or just going the lazy route and using the dedicated sub speaker leads since they already have a filtered signal somewhat and are in the right location.
I honestly never planed on adding a sub, but the factory infinity unit sounds so light too me and since I give it the work out, already sounds like it's on the tail end of it's life. I was surprised because the infinity systems I have worked with before almost always were underpowered safely.
I was originally planning on using the factory amp for the rest of the system but I do have an extra amp and a set of components I could throw in.
Could you explain the ways to fake the signal please?

Oh, and I had no idea the firmware situation existed. Thanks again for the information.

 

Faking the signal is not for the faint of heart. First you have to figure out exactly what the signal you need to fake is (there are sites on the web dedicated to hacking the CAN bus -- try searching on the words 'CAN', 'BUS' and 'HACK'). Then you will need to purchase a CAN bus interface chip, program it to send the signal when it sees the vehicle has started up (other signals available on the bus indicate this) and bingo, the radio will believe that there is an amp on the system.

The easier solution would be to purchase 'the' amp that comes with the upgraded system. You would be able to use one from a 2007 Nitro or Sebring as well as the JK. You might even be able to use a blown one as all you need is the CAN interface, not the amp itself.

As far as the Sub out is concerned, according to the wiring diagrams, there isn't one. I believe that the crossover that separates the sub base is in the amplifier, not the radio. Unfortunately that's not the news you want to hear, but it is the way that DCX engineers designed the system.

 

Indeed this CAN hack does look like quite the ordeal. I did find several sites, one of which was created by a member of the LX forums and is very detailed.
Your right about the crossover. Do you think there would be a significant gain in signal strength by doing the hack or would I be better suited to just use a converter at the source? The amps I will be using have a good adjustable (variable not just the switch method) crossover network with subsonic filtration and accept signal levels as low as 200mv.

 

Before looking at hacking the CAN bus, I'd install what you have and see how you like it. Since audio quality is such a subjective thing, you may be perfectly happy with the high power connection. If you aren't then I'd consider alternatives, including hacking the bus.

Good luck, I hope it turns out the way you'd like.