For the rear doors with the Hertz 1650.3, I would keep the gains down so that the rear pillar does not get drowned out. The speaker is on the border between SQ & SPL.
With the Alpine DSP in the 5.1 mode that is correct you can not use the passive crossover's the way you what to and you will lose the rear pillar. Alpine method for the 5.1 setup concentrates on tuning the front stage, which is really the key to a surround sound setup. The time delays on each channel is the key. How Alpine allowed themselves to go away from that concept with the OE factory system is beyond me.
Just for S&G:
If I was using the Alpine H800 with your Hertz Speakers and passive crossovers, here is how do it to take full advantage of everything in a 5.1. However, you will need a 3rd amp. The passive crossover on the 1650.3 is bi-amp, allowing for a cleaner and a proper power.
Set the Front mid to full range and the hi to full range. Now you can use the passive crossover for the setting for the speakers. The Alpine now allow you to eq and time each channel.
The center is the center speaker using the 700.3. Now you can set up xover and act as band pass, eq and time delay.
The rear door the 1650.3 woofer only and passive crossover. IMHO, because of the interior size of the GC, too much tweeters does not work in this case. Alpine actuarial got this right and I guess Chrysler agreed. In my setup, one pair of tweeters only and everybody is amazed. The 700.3 for the rear pillar. You will be using the passive crossover here as bi-amp as well.
For the amps: 4-channel amp with 100 watts for the 6.5 drivers. And the JL Audio 600/6 v2 for the tweeters, center and rear pillar.
Yes, this is more money this way in terms of interconnects, multi power amp kit and a 4 channel amp. You will save on the install since you are doing it yourself. Using the Alpine H800 in a 7.1 set up with the factory DSP will additional cost since you have to connect at the output stage of the factory DSP and do summing for the fronts and sub. The rear door is run of the factory.
Any way, keep us updated.
Best for now.
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