Adding 12 inch sub and mono amp beside existing 10 inch sub and 5 channel amp.

I just installed the ********* budget system with a 10 inch sub on a 5 channel amp along with front and rear door speakers, tweeters, and crossovers. Came with 8 ga power wire.

What's stopping me from getting another custom enclosure to put behind the passenger back seat, putting a 12 inch sub in it, powering it with a mono amp next to the 5 channel, and replacing the 8 ga wire with 4 ga?

The door speakers and tweeters seem like they're plenty loud, and the 10 inch sub is much better than what I had. It adds punch to the music and will shake my rearview mirror in the right frequencies. It does have its limitations though. If I use the same brand of amp and sub, and had them in separate enclosures, would I have issues?

I think I'd port the 12 inch box so that it hits harder on EDM and R&B. I'd have 2 remotes for bass adjustment so I can turn down the 12 if it's overpowering on rock, country, etc.

Along with sound deadening, in my head this sounds like a perfect setup.

What do you think?

 

Generally speaking it's not a good idea to have 2 different-sized drivers playing the same bandwidth. Ideally you'd just remove the TT stuff and replace it with a new sub. Or add another of what you already have - just use the same size and keep the enclosures the same.

A ported 12 is going to need a lot of airspace...maybe 2 cubic feet or more for the enclosure and then some for the port (my port is half my enclosure tuned to 29 Hz). You can't just toss a random port in some box and expect good results. Considering the space behind the seats, you're probably better off with a sealed shallow-ish 12 - and even that is going to be tricky to fit.

Sound deadening is always a good idea

 

This is pretty much my conclusion after reading up on the the subject tonight. I think I'm going to focus on sound deadening for now and just enjoy what I've got. It is much much better than what I had.

 

Ported and sealed subs in the same cab is a big no go.

And as said above running different sub sizes can cause issues too.

I would run the current amp to the mids and highs, then swap your box for a dual 10 setup and run them off a dedicated sub amp.

And yea you'll definitely need to upgrade from the 8 gauge power and ground.