Large Open Space ; DIY Sub better bang for the buck than 2 x Dayton 1200's?

I'm somewhat helpless to try to pressurize the whole space, since it's probably well over 10k cubic feet:






Also, it's a condo, so if it gets too intense, I'm going to have some angry neighbors. We're pretty well insulated though, fwiw.

So the plan was to get two Dayton 1200's for ~$200, since I'm on a budget, and place them in opposing corners of the seating area. The hope is that the proximity to listeners could give a great listening experience even if it couldn't fill the room entirely.

I would imagine DIY can yield a better sub for the same money. Ultimately it comes down to this - can the audience enjoy a better listening experience (60% HT, 40% music) with a DIY setup in the $200-$300 range vs two Dayton 1200's?

Thanks all!

Edit: I should add that the fronts will likely be KEF iQ70's, and the center channel the KEF C6LCR. For now the surrounds are Polk Monitor70's.

Yeah, the tall/open floorplan makes it look much bigger than it actually is. The finished basements puts us at 2200 sq ft - was about 1550 before that. That big space just makes it seem so much nicer than surrounding condos

That said, it's not so good for filling space with sound, lol.

For movie nights, here was the idea for our setup:




We'd have to have the projector closer as we discovered, but seating will be adjusted similarly to pictured.

I see, well I'm open to figuring out what we should do, then saving a bit to do it would work.

So are you saying two drivers in a single box if I can swing it? Or two separate complete subs altogether? If the latter, then one after the other could work to get me something sooner. Otherwise I can just roll with perhaps a single $100 Deyton to tide me over till the money and construction is done.

So what are the key advantages to doing this DIY and spending a bit more money? Just more power, or is there more to it?

Holy cake... I know I said space isn't a limitation, but I didn't think subs would get to the size of refrigerators. While I love the idea of the immersion factor, there's no chance of my wife tolerating even one refrigerator-sized subwoofer in our living room, let alone two, unfortunately. Anything with remotely similar performance at maybe 1/3 of the size max?

Edit: That said, I like the idea of filling that much space for only $350. If there's a way to do it quite a bit more compact, I'd like to look into it.

From Appearance/Size aspect, the dual 18's with the duratex coating looks great here: http://www.avsforum.com/t/1435795/first-diy-project-for-a-guy-looking-to-upgrade-multiple-sealed-18s/600

We'll be needing to buy a lot of furniture, so having these to double as an end table or two would be perfect
Edited by ahheck01 - 12/26/12 at 9:48pm

Hmm, so it sounds like variations of the F-20 are much much bigger bang for the buck? For a space that big, would sealed subs be a very impractical move?

ie. I can see building one of the 2x18" sealed boxes, running that for a bit while saving and assessing the need for a second. I would think they'd make great simple/minimalist end tables based on their approximate size, so the amount of room taken up would be far less of an issue.

As for the F-20 variants you pictured, take note of the layout I pictured and mapped out above - there's really no place to hide the subs, unless they double as usable furniture. That's what I'm running into with this livingroom setup.

Also, just to keep this on the radar, I do have neighbors on the opposite side of that big wall to think about, so while I do want to provide the best listening for the HT viewer and music listener as possible, I think having 1000% lifelike shuttle launches may be a tad bit irresponsible given we share walls in the condo. They're well insulated, but it can be heard when the neighbors accidentally slam a kitchen cabinet that's mounted on that shared wall.

Edit: I'm also open to the coffee table idea, though I haven't the first clue on how to make a THT look good as a coffee table. Open to inspiration there.
Wow, honestly I think that's 80% better when it comes to the WAF, but we still have the issue of placement. In their ideal location, they'd be blocking the windows or fireplace. Based on the functional and cost effectiveness of the THT/F-20 approach, that seems to be the best idea functionally, but practically I just don't see how it would be possible, unless someone really creative can show me some strategic placement based on the photos etc of the above.

It seems like end-table subs are my option. I do like the idea of the functional difference that a sealed design makes. I heart extension.

That said, I just got an idea. It's a crazy idea, but it just might work. What about having the THT/F20 in the loft? Here a photo of it. The short wall that's barely in the left side of the photo is the wall that overlooks the living room.

I'll have a large desk in there, eventually with a 27" iMac and two 27" displays flanking it. I'm not 100% about placement yet, but I assumed an L against the short wall and against the adjacent big wall. I'll also have either some bookshelf speakers for that sound system, or I'll use my current Polk Monitor 70's for the stereo. If there's a big sub already up there, I could just use it for both?

Anyway, is the loft idea an option? I think the space is there? Would the THT/F20 be detrimental to neighbors?

Pic of loft:

My other idea, if I went the sealed route, is to make a coffee table for the living room as follows:

Surface would be a 6' x 4' glass surface.
Stands would be two sub boxes with dimensions 18" x 18" x 36", with dual 15" drivers in each to eliminate vibration and for extra output. They would be parallel to each other, 2' apart, leaving 6" of glass extending over the edges. Like this:

Yeah, if I'm going to build a DIY sub, I'd like to get some significant extension that I couldn't get at the same cost going retail.

Bump?

I would also be open to a coffee table THT setup if it was possible to average out the depth and height of the low profile one, and go 18 x 42 x 42.

Also, as an update, the living space is open to a total area of about 12,000 cu ft, all inclusive.

By coffee tables, do you mean a couple end tables? Ballpark dimensions? I'd love to get a little lower extension, would it be possible to do two sealed cubes instead of the two ported boxes?

So it sounds like the best of both worlds is to spend a little more to make two sealed 15s (or 18s?) - start with one, and go from there?

Would a single dual opposed work to cancel vibrations and fit more in less room, or would two separate sealed 15s or 18s be a better choice in this space?

Okay, other than the vibration issue, what trade offs are there to down firing vs side? I don't mind taking stuff off for HT use.

Also, what would be the key cost and size restraints of 15 vs 18?

Ps thank you for taking the time to share your knowledge. I've spent so much time searching, that its really nice to have someone with the knowledge chime in on my specific situation.

Hmm, perhaps I could start with a single sealed down-firing SI 18 and go from there. Do a 22" cube with 3/4" MDF or plywood (what should I use? I can get solid birch or cherry for super cheap too). Internal space ignoring bracing and the driver would be about 5 cu ft. Then use 3-4" legs to bring it up to nominal end table height, and give the driver room to move some air. Will that be enough? I have carpet everywhere - will that affect things, or should I put another wood panel underneath it by a few inches?

The final challenge is that my vision for side-firing enabled me to put the contacts on the bottom, not showing. What's the normal solution for down-firing end table subs to hide the contacts?
Edited by ahheck01 - 1/2/13 at 11:31pm

In-progress shopping list:
Driver: SI 18: $190
Box Wood/Materials: ? : $?
Amplifier: 500w yung plate amp: $200 Behringer EP4000: $270
Total for first one: ~$460 + Wood/Materials
Total for second one: ~$190 + Wood/materials

That averages out to $325 each + wood/materials - is that pretty good value for 2 x 18" sealed subs with 650watts to each?

Edit: Since I may add another in the near future, it was suggested that I get the EP4000 for a little more, which can handle the second one when I build it, too.