THT (or THTLP) in ceiling?

[Alfalfameister]

I have a THTLP (https://billfitzmaurice.info/forum/view ... hp?t=26504)

I want to add one (or two?) more to the ceiling, like this guy (minute 32 of the video).

https://youtu.be/l5N1L_6wob4?si=_y2xjyi4wsolaMif&t=1920

Like him, the reason is so I can keep empty space in the living room, and not have to worry about the Wife Acceptance Factor, with two huge subs in plain site. So, I like his idea of "hiding" it in the ceiling.

Would a THT LP wide side mouth opening be good for this? or regular THT with mouth facing down?

(I will add vents/discrete holes in the ceiling where the mouth will be facing).

Or would I be better served with something else? (infinite baffle maybe?).

I'm so pleased with my 30" width THT-LP, that I just want to build more of them. But they're huge...

[Bill Fitzmaurice]

It can be done, the only issue is finding the best placement.

[Alfalfameister]

As I already have a THT LP, this (or "these" if I build more) would be supplemental.

The guy in the video tried to find the best place, but then also hit physical constraints (some rafter in the way or something). So, I might have some limitations as well, but the primary purpose of adding more subs (in the ceiling in this case, so it's out of the way) is to minimize the room nulls. More subs not for more bass, but for better bass.

I will use minidsp 2x4HD and Room EQ Wizard to help me out. While the final location in the ceiling might not be the best place (maybe there are internally recessed downlights there or whatever), my plan is to make the most of the subwoofer regardless of where it is placed by EQing it properly, and making it work well with the other subs.

[Rich4349]

It won't be easy, but you could use two tall, equal sized step ladders to support your current sub up near the ceiling so that the mouth is close to where you want the hole to be. Try different locations, listening at your listening positions to see how it sounds there. A spider-walk version of the "sub crawl".

[Bill Fitzmaurice]

That's an option, but don't listen with your ears, listen with an RTA. A response bump, especially one in the upper bass, will subjectively sound louder, but the entire point of multiple subs is to remove response bumps and fill response holes.

[Alfalfameister]

The main constraint here is the WAF.

I already have a THTLP (30" width), and it looks good as a console table behind the sofa (also probably not the OPTIMAL place sonically, but passed the WAF, and passed it with flying colors! - see my build thread, there on my signature).

I was allowed another sub at the corner of the room after I showed her another THTLP standing up, but that corner will have a 15x18x72 with "only" a 12" driver.

In the ceiling in the rafters, I can fit even two 36" THTs or THTLPs.

After being impressed with the capabilities of a minidsp 2x4HD in EQ'ing to account for the bumps and nulls, am thinking I can make it work.

They don't have to be OPTIMAL, but am hoping the additional subs can make the whole system BETTER (maybe not the BEST they can be, but BETTER just because of having multiple subs that have been EQ'd correctly).

And I get to do it without having any additional visible subs in the living room.

[Seth]

There's a lot of room for "outside the box" placement. If you have a basement or crawl space, the subs can be put under the floor, firing through a grill on the floor (which can be covered with carpet). If there is a wall that has exterior on the other side, the bulk of sub/s can be placed outdoors and just create a water/airtight seal to the exterior wall, frame out a port the size of the horn mouth through the wall and put a grill on the interior. Cover it with cloth, whatever suits your decor, or just make it look like a HVAC register. Same can be done if there's an underutilized space on the other side of an interior wall, like a garage or closet. Even if it's unreasonable to put the subs "in" your ceiling, you can bolt them to your ceiling to get them off the floor and tie them into the decor somehow. Maybe continue the contour of the cab along the length of the wall creating a faux soffit that blends it into the room. Perhaps put some can lighting in, or a shelf for random tchotchke, family photos, or decorative keepsakes.

Food for thought.

[Grant Bunter]

The main constraint here is the WAF.

I already have a THTLP (30" width), and it looks good as a console table behind the sofa (also probably not the OPTIMAL place sonically, but passed the WAF, and passed it with flying colors! - see my build thread, there on my signature).

I was allowed another sub at the corner of the room after I showed her another THTLP standing up, but that corner will have a 15x18x72 with "only" a 12" driver.

...They don't have to be OPTIMAL, but am hoping the additional subs can make the whole system BETTER (maybe not the BEST they can be, but BETTER just because of having multiple subs that have been EQ'd correctly).

Hmmm.
Some clarity would be good.

One second you're saying it's not about volume, it's about response, then you say "it's only a 12".
Then you say it's about better coverage in the room, but the result doesn't have to be optimal.
Sorry, I'm not having a go at you at all, but it's confusing to me.

So, if you're going to spend time and money building more cabs, I think you need to work on WAF factor.
I totally understand, WAF factor in my home means nothing more than small cabs for stereo with a single small sub.

I think you're aware that subs need to be in their ideal locations to do what they do best.

Is it possible to move your current sub to the wall behind the sofa instead of just behind the sofa (based on best positioning dictated by the subwoofer crawl)?

More often than not, HT subs work out best response wise if there is one per wall in the right place of a standard rectangular room.
Sounds like you may not get there, but moving current sub to the rear wall, and a 12 in a front corner, may do much more than you realise. You might not need to install ceiling subs in less than optimal positions at all.
Unless you just like building, but that's a whole other conversation...