6 Speaker Base with Hemi and ANC. I just wanted to bring some impact to the system so at least for now, I just added an amp and a subwoofer. I was looking for sound quality and accuracy. Musical taste - rock, classic rock, metal, and a bit of country (but not too much). Went with a sealed box for a smoother response and less concern of needing to tune things with a port. I was originally looking for a single 10" but due to not much of a cost difference I went with a single 12".
Subwoofer: A single Dayton Audio Reference HO Dual Voice Coil 12":
https://www.parts-express.com/dayton-audio-rss315ho-44-12-reference-ho-dvc-subwoofer--295-467
I went this direction as I have an older Dayton Titanic Mk IV 15" in a DIY box driven with 600 watts for home theater duty. It's been a stellar sub that has held up to a lot of abuse over the years (10+ at this point I think.) Dayton's are fantastic subs and at a very reasonable cost for what you get. For the price, the big name car audio brands can't really touch the Daytons for sound quality and value.
Amplifier: Alpine MRV-M500 - 525 at 2 ohms mono. A good value and a good match for the Dayton.
https://www.amazon.com/Alpine-MRV-M500-V-Power-Digital-Amplifier/dp/B00BMR7UPS
Box I went cheap and because some of the popular boxes are either not available right now, or are ported which I didn't want. They likely wouldn't have been tuned correctly for my sub anyhow. They offer 10" or 12" dual sub boxes: . Thought of building my own but due to a lack of a table saw, and the many angles I would have to cut, it made sense for me to go pre-built.
http://www.qpowerinc.com/details.aspx?product_id=20192
The box left me with a weird design challenge as I was going to cut it in half since I only wanted to run a single sub and have some space for underseat storage. As there is a pattern on the front of the box, I instead decided to leave as is, except I cut the top off of the second half to keep some storage and for a place to install the amp and have easy access to it's controls and wiring. This also allowed me to keep the look symmetrical and more concealed. The center divider in the box wasn't well sealed from the factory, so some construction adhesive and wood glue was needed to truly seal it up tight.
I completely bypassed the ANC with the iDatalink bCH3:
iDatalink bCH3. Super easy to use and preserves the factory wiring for the ANC if I ever want to go back to stock. Frankly I have noticed zero difference without the ANC but then again I do have Carven exhaust and now some bass. Even with the stereo off, still not a difference without the ANC that I can hear.
I did not use a LOC or DSP. I just used the high level inputs of the amp. Maybe not the best way to go but I was trying to keep costs low and frankly it works great.
This setup really impressed me with it's accuracy and impact. I have the gain on the amp turned down quite a ways to blend better with all of the factory door speakers but it really rocks. You can FEEL the kick drums and hear all of the bass notes clearly and they are well defined. This is no one note wonder. I absolutely love it. I suspect at some point, I'll add in a 4 channel amp and upgrade the door and dash speakers but for right now, mission accomplished.
Wiring still needs some clean up and some wire loom but this is how it sits thus far.