There is absolutely no way to do a quality sub w/enclosure, amp and dynamat for $200 even if you installed everything yourself and bought used. Keeping sound quality in mind, you'll spend that alone on just the sub. A quality amp to run a single sub will run $300-$500, then you'll need an enclosure, so that's another $150-$200. A shallow mount sub will run another $300+ This is assuming you want better sound than what you can get from Walmart. Before it's all said and done, you're looking at around $1000 to add a sub for self install and another $200 for labor if you have it installed by a car audio shop.
You’re at least right about one thing, it was more than $200
http://www.fordraptorforum.com/f266/added-sub-52819/?highlight=added
w/o the single sheet of dynamat I needed for the enclosure I was at ~$225 and did the work myself. This assumes that there’s an existing sub and box from Ford to work with. I really liked the results of adding dynamat to the sub enclosure only so I’d budget about $275 for a reader with an 802a truck or one with the factory sony / b&o.
The results are price point amazing. Is it an audiophile improvement? no, and I didn’t expect as much. It doesn’t take up any more room in the truck, bass and overall sound are significantly improved. Nevertheless, I get crisp, clean sounding bass and it improves the totality of the sound.
Most humans have trouble distinguishing between quality subs of similar size and price range. Many convince themselves the one they want to like sounds best, but if you blindfold test them, a lot of folks end up liking the sound quality of not so expensive subwoofers. This doesn’t make them better units, but audio selection is personal and subjective, so you can easily overspend on something that you or me say is “the $hit”, or blindly buy on some BestBuy sales-bot recommendation.
The major issue for the 802 or Sony/B&O systems is the sound processor which both muddies the mid range and bass, as well as rolls off the bass at higher volumes. To get a clean, pure signal, we need a sound processor and as you point out it’s not cheap, easy or simple.
Subs can be addictive, once you have one, you realize the sound you’ve been missing and want more. If I could have for a reasonable amount more I’d have gone for about another 100w knowing what I know now, but I don’t want to give up room or floor space for a sub.
