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Discussion Starter #1
I started a build log on this forum about a month ago with most of the "build" being my sub/ent. center combo. I didn't even know this sub-forum existed. So I will have a bunch of photos up front and then they will slow to the progress of the build. The build log is here: http://www.hometheatershack.com/for...ion/46140-first-ht-build-swinging-fences.html

I wanted to build a LLT setup. My wife did not want sonosubs. What to do??? I decided to build a 8ft. long box that would sit below my tv, between my towers, and also house all my av gear. It couldn't be taller than 33in. overall since my center channel will sit on top and I wanted all of my tweeters on the same plane. So the fun begins.

What I ended up with was a overall length of 96"x33"x22" with 12.75" of the height going to the av portion of the unit. The overall volume is 9.96cu/ft after displacement for each sub w/ a 36" long port that is 6" in diameter. This gives me a tune of approximately 13hz. The apparent volume will increase and the tuning will decrease slightly since I'm going to stuff the box with polyfil. I'm using the "tried and true" amount of 1lb./cu.ft. Which equals 20lbs. total.

I'm not going to narrate the pictures starting out, but if you have any questions or comments...please feel free.

One quick final note, the final product will be black to match the rest of the stuff in the room. I used cherry for the sketchup model to contrast the speaker grills.

















 

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It's coming along well. If you still have the box open you might add a few rib braces(small piece of wood connecting one side to the other. You don't need a lot for a sub, but with a box that large it's better to be safe.

If you already got it sealed up don't worry about it.

I look forward to the next steps.
 

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Discussion Starter #8
I really like the design, should have a very high WAF.

I'm always a fan of big subs, looks good!
Yeah, my wife 86'ed the sonosub idea. Since she 'let' me build this thing, I figured I could try and come up with a more asthetically pleasing solution. I'm pretty happy with the results so far too. I got the thing boxed in last night. It was raining here so I couldn't cut the wood (I do that outside the garage) for the shelf part, but I hope to have it done by tonight. After that I'm down to patching and painting! :D

Just curious, how big is the HT room?
I'm honestly not sure volume wise. The dimensions of the room itself are approximately 14'-6" by 14'-6" for the theater area. The area where the desk is (and where I moved the attic door to) is appoximately 5'-0" by 10'-0". The ceilings is 8'-6" I believe. The problem is that the stairs have no door and the room overlooks the living room. If we don't close bedroom and bathroom doors, the entire floor plan is actually open...including the bonus room.

I'm not expecting much room gain because of this fact, but I also don't like the way bass sounds when you corner load the subs for boundary gains. I do have another 12" sub that I can use if the 40-80hz output is a bit weak or if I'm sitting right in a null to help even things out. I already have a channel unused on my Emotiva XPS-5 (two actually since I decided to not bi-amp my mains) and I've still got two channels of control available on my miniDSP as well.

Was there a reason other than above that you asked? I come from car audio, and I read a good bit on home audio before moving forward with the project...but I don't pretend to know everthing there is about either topic and I'm always open to learning. :T
 

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Discussion Starter #11
I was modeling the subs and wondering about room gain. Without any, it shows 114 db at 12 hz with 1000 watts. Looking forward to your impressions when you play your first deep bass movie!
I'm not entirely sure how much room gain I'll get. The area is very open, like I already mentioned, but I'd honestly trade a bit of output for less cancellation due to reflections. That is why I put the subs so close to the ground, the frequency where the largest null occurs will be pushed higher into the passband, hopefully high enough I'm not effected by it at 80hz.

The model you have looks excatly like mine except yours is around 3db higher. I think that is because I'm only running an EP2000 (not a 2500 or 4000). It should give me around 575w/ch. instead of the 950w/ch. the other amps are rated for. I think I'll be happy with that, but if I'm not, I'll probably go the route of adding another amp and another pair of drivers (this won't happen until my next house). This will increase the output while keeping distortion low AND allowing me to move some of the subs around to fight nulls.

BTW, I'm "saving" WOTW and Black Hawk Down until I get the subs up and running. :D
 

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BTW, I'm "saving" WOTW and Black Hawk Down until I get the subs up and running. :D
Save Tron: Legacy and Battle: Los Angeles too, your neighbors are going to hate you:T

Nice build by the way, can't wait to see it completed.
 

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Discussion Starter #13
It's been a while since I've made any updates...but that doesn't mean I haven't made any progress. 60 hour work weeks out in the heat leave me with little desire to upload photos after working on my box in the heat. :) Alas, I have hit a "milestone" with the build and so a massive update is in store.

I'm actually about 90% done. All I lack is building the center drawers for the blu-rays and remotes and getting my shelves painted black. But enough talk, on to the pictures!

Test fit:



I put the terminals on the top of the box so I could get it as close to the wall as possible:



Dowels for the grills I'm building:



Working on the top:



I chamfered the back to allow the components to "breath" but still be invisible while seated:



Close-up:



Cutting out holes for wires:



Building the speaker grill frames:

 

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Discussion Starter #14
And now things begin moving quickly:

Painted "test fit" in the garage:



Finished grills:



The path we took to get this beast upstairs:

Through the front door and into the kitchen (moved the island for room to rotate):



Down the hallway but immediately up the stairs:



First turn:



Second turn:



Safely upstairs and installing the subs: :)



Getting it up to the wall:



"Wingspan" shot (me and my father):



Where it sits till tomorrow (I have to be back to work in 4 hours):

 

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Nice progress.

If you don't mind, where did you get the drivers? They seem pretty expensive from looking at the sources I'm familiar with. I'm trying to figure out my next project.

Hope your cars are ok outside. This is my wife's (and my, admittedly) biggest pet peeve about subwoofer projects. They take the whole garage! Anyway, hope you're doing ok with that. Should be a great system when you're done!
 

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Doh, you posted when I was posting! I love your grills, they came out awesome! Oh yeah, you need a bigger tv.
 

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G'day pionkej, very nice build progression. Looking forward to your listening impressions. By the way, has anyone mentioned that you could use a larger TV? Cheers, Mike.
 

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EXCELLENT work.
 

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Discussion Starter #19
Nice progress.

If you don't mind, where did you get the drivers? They seem pretty expensive from looking at the sources I'm familiar with. I'm trying to figure out my next project.

Hope your cars are ok outside. This is my wife's (and my, admittedly) biggest pet peeve about subwoofer projects. They take the whole garage! Anyway, hope you're doing ok with that. Should be a great system when you're done!
I found these on craigslist for around $450 shipped. I picked them up several months ago, so I can't remember an exact price.

You are correct though, they are excellent drivers. They have magnetically opposed voice coils that basically prevent the sub from bottoming out. As the coil begins to leave the gap, the other opposing coil applies the "brakes" and pulls it back in. I'm not sure if my amps are powerful enough (they may clip before max output), but if they are, you basically set the gains by turning them up until the output stops increasing. At that point, you have hit max excursion and the subs are using the opposing coils to prevent bottoming out. Turn the gain back a hair just to avoid generating unnessary heat, and your gains are set.

BTW, these are great sounding subs for IB use too, and the "braking" characteristic is even more helpful there. The only problem with IB is you need lots of displacement for output and these things are not cheap.

Doh, you posted when I was posting! I love your grills, they came out awesome! Oh yeah, you need a bigger tv.
G'day pionkej, very nice build progression. Looking forward to your listening impressions. By the way, has anyone mentioned that you could use a larger TV? Cheers, Mike.
:D Seriously, the cabinet makes my 55" tv look like a 19" computer monitor. BUT, I think if I told my wife I needed a bigger tv than that, she would either kill me or fall over dead...either way, somebody would not survive the conversation. :yikes: So I'll hold on to my tv for now, and I already have plans to move to a projector and a dedicated theater when we move into a larger home in a few years (that's the plan for now anyway).
 

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Ha ha yeah, when I saw the wingspan pic I realized how big the cabinet is. 55" is bigger than mine! I need a bigger tv though. I'm waiting to finish the basemen, projector time! :D
 
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