Custom DIY Sub(s) Build

They will be built into the wall (shimmed and screwed to the studs from inside the box). My thought was, since the front panels will be hidden by the couch, I can simply use some silicone to seal them, and leave the screws exposed, so it would be as easy as removing the front panel and scraping off the silicone if something major happened. In the event one blew, they’ll be front mounted, so that’s a simple replacement, though I’d be deaf.

I may have an idea or two













I don’t know if I follow exactly how you plan to do the sub mounting. How much room can you get between the sofa and the wall?

For your front book case of you want a projector you can make it so it tucks away. I will get a motorized one soon with enough black on top so when the screen is up you don’t see it.

I have def tec inwalls LCR and front heights mounted in the cabinet.

Power the subs with a 4kw speakerpower plate amp (no fans so no noise since it’s close by)

You can use your built in tuning program in your receiver of choice. If you want more real tuning look at a program called R.E.W., a device called a hd mini dsp and a mic. There will be some reading and learning to do but it’s supposed to be worth it. I have not got to that point yet.

My subs are Dayton audio 18s from parts express. So are the boxes. I’m about to turn that into a bench seat...and it’s going to be fun for the ladies to sit on

So far with a rat shack all meter and one bass song I decided to try out I hit 126db. Not bad considering how much open space it fills. Room it’s in is 22’x21’x12’ and 2 walls are pretty much completely open to kitchen dining and so on.

Nearfield subs give you an amazing tactile experience! I would see how much space you need and put the biggest subs you can.

Did you custom build the entertainment center/bookshelves? That’s gorgeous and the in-wall speakers are super stealthy.

That's a stellar setup. Well done sir. Next time (also first time) I'm in baton rouge I'm swinging by and we're watching top gun.

You can probably hear it from BR....but I’m in laffy

Ahh that should work...I thought you were trying to attach the subs to the studs and use....ahh never mind not important lol. All you need is about 1” being the sub and then proper airspace.

What JBLs? I have a few of those too Best Buy has them on sale 129 down to 29 so I got 16 of them for I think those only need a cube or so of airspace. If it is the same ones you definitely want to get that mini dsp and boost the low end. I have 8 way underpowered in my garage.

Yea I couldnt pass up that deal...I had 2 old SVS tubes in my garage but I replaced them anyway with these. They dont go as low but hit harder. On avsforum they said they have a higher native freq but you can boost them down low a lot. They claim 4 of those 12s is equal or a tad better than one of those 18s.

Since once you build that box you are stuck with it I would make it a little flexable with other 12s if you can just in case it doesn't scratch your itch. You can always fill room in the box to reduce the airspace if its too big for the JBLs.

If you look on avsfoum and look for those parts there is a bunch of info...almost too much lol. But theres a thread that once you figure out REW and have the equip you can post graphs and get help on the tuning part. I havent got to that point.

I think 4 12s behind the sofa would be great. The good thing about near field is you get major headroom. I have to almost turn the volume knob on my plate amp off to get it where it needs to be to run the audio setup on my denon. You dont get the room gain if they were else-ware but if thats your only spot its not a bad one.

You can do a little tuning with a built in on a amp but that mini dsp is massively more adjustable. You use REW to run sweeps and see your freq response at your MLP and then you have a ton of adjustments in that DSP to flatten it out. You can lower spikes but cant really raise a void. I have some gaps in my sweep I can hear that I may have to live with. Also I may stick another 18 in that cabinet but because theres a spot that I think it will help my dip at the MLP. You can always add the DSP as well and use what you have at first.

Plus you get the impact of the subs that adds a ton of fun.

Those subs are on sale right now?

Yea DSP is for Digital Signal Processing...the box I’m talking about happens to be called a mini dsp. There are amps and avr’s That have some built in. It just all depends on what your equipment can do and if you want more tweaking.

That’s what I was referring to if you wanted to replace them down the line. Like make the box as deep as space allows Incase a better sub you buy is deeper. And you can add cut 2x4 to take up airspace if the box is way too big. I’d think 1-1.5cft would be good for most any 12 you would use but I’m not positive on that.

When you run your AVRs setup (what ever it’s called depending on what avr it is) it will blend all the levels together. Get a digital radio shack SPL meter (shite....are there any still open lol) and you can measure in the MLP after and tweak if you need. With the subs close you may end up with a lot of headroom and that’s ok. I’m a bass head so I run them hot (5-10db over reference) but my Def tecs can keep up.

I have a Denon 5200x and FHA’s running the 9 speakers LCR, front height LR, L/R surround on the side of the MLP and LR rear surround behind the MLP. Sub output to the plate amp via a SVS wireless setup because my electricians were stupid and couldn’t follow simple instructions to run a empty conduit in the slab.


Not sure Ken I got the JBLs and the Dayton’s around the same time last year around Black Friday.