I have purchased the integral audio harness to install my subwoofer and amp. I've then thought about the whole decision some more and I feel like I could have just done the line-out converter and called it a day, especially since posi-taps makes it super easy. Does anyone know of have any reasons besides the simple plug and play as to why the harness is better?

 

Funny you should ask....I happen to know the answer to that! There are two reasons. The obvious one is convenience. The less obvious and far more important reason has to do with the signal level and the headunit.

Our harness has passive circuitry inside the RCA overmolds that does two things - it knocks the signal down to 4V max, and it loads up the BTL output transistors inside the headunit.

The output transistors in the HU are designed to run with a load, like the speakers that it normally drives (the HU is the same in 6 spkr and HIFI/HK vehicles). The headunit sees the typical 10k-20k input impedance of an aftermarket amplifier or other component as essentially no load, and when presented with no load the BTL output voltage will spike at higher volumes and the overvoltage protect circuitry will activate, shutting down the system until the vehicle is restarted.

Would a line output converter address these issues? Depends on the LOC. Your basic $30-ish type is a completely passive, very basic affair. The output won't be adjustable, so it will be sized for a higher input voltage and will knock the signal down too far, reducing your S/N ratio significantly. It may or may not load up the HU. Your more advanced, fully adjustable, high quality 4ch LOC's will solve the issues, but you'll pay $80-100 for it - as much as our harness, and you'll still have to find a place for an extra component, run the wiring, and identify/tap the correct wires.

I'm not trying to sell you on this. We make almost nothing on these harnesses, and I'm constantly considering pulling them because selling them is more trouble than it's worth. We really only made them available as favor to the DIY community. But the demand for them is there for the reasons I've listed above. You made a good purchase.

 

Just re-read the OP it looks like you may only be adding a subwoofer, and not replacing the other components. If that is the case, loading up the HU isn't an issue, and S/N is a bit less of a concern. As long as you get usable voltage from an LOC you'd be ok. You'd need to make sure you tap the correct wires (you can't use the rears in 6 spkr systems, and you have to use input in HIFI/HK systems). Beyond that, it's a matter of convenience/time/reliability/risk (tap the wrong wire and you can cause yourself some serious grief). Only you can say if those are worth the extra $$.

 

I appreciate you answering. In all honesty I was hoping I would get a direct answer from IA. I'm glad you all make the harness and it's available to us DIYers. I've just been reading around and thinking about the install and I felt like the LOC was simple to do with the posi-taps. But I was pretty sure there were other advantages to the harness, I just did not know what they were, besides convenience.
I was aware of the rear speakers not being used for LOC and I read in the instructions that were emailed to me you all used the front speakers so I was happy to read that. I would only be adding a subwoofer for which I'm going to make the box because I already have a RF 10" and amp.
I'll keep the harness though because if I ever decide to add component speakers the harness already has the other 2 rca output available for that.

One quick question, in the m1101s instructions you mention tapping the pin 1 for the remote wire. Does that still stand true or is there a cable on the harness that is ready to be used for remote?