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Hey guys,
I just joined the forum but I was too excited not to share. So here we go!

A few months ago I was getting a real bad itch to build another subwoofer, (I've build a few before) but had somewhat of a dilemma. Being a college student living in a small house with very little room for speakers, I didn't have anyplace to put a proper sized subwoofer. Shortly after admitting defeat and accepting that there was just not enough room for another sub, I happened upon a large piece of glass that had come off of a coffee table. Right then is when I decided that I was going to make it. A coffee table with a subwoofer inside of it.

After some driver selection and a bit of SolidWorks designing, I came up with this:




That ended up being a rough mockup and didn't actually have much in common with the final design (except for outer dimensions).

I decided to go with a 15" Dayton Audio DVC Subwoofer in an 5 cubic foot, vented enclosure.

Here is the build from start to finish!
(Sorry about the poor quality on some of the pictures)



Pieces cut out




and stood up to get an idea of the size.




Drilled out holes for the glass mounting hardware




Box assembly and bracing (Clamping with the help of some pipe nipples)




Holes for sub and port cut out
In order to get the sub flush with the top of the table, the router had to plunge almost an inch into the top baffle. I decided to make a small ring that would help hold the sub. (A triple baffle of sorts?)




The build took a turn for the better when I got my hands on some walnut veneer and chose to cover the whole thing.






Stained




Installing mounting hardware (Pipe flanges and nipples) with the glass on top




Finished product without the glass (sorry about the laundry in the back)




Here it is, completed, in my home







As for sound?
It is immense. It rattles glasses in the kitchen but the glass top barely vibrates. At very, very high volume it is only slightly noticeable, and undetectable at more typical operating volumes. I am no audiophile and I'm sure I don't have a properly trained ear, but it reaches extremely low (tuned to ~18Hz), while still being tight and punchy for bass drum hits. It is without a doubt one of the better performing subs I have ever heard and still looks great while doing it.

Let me know what you guys think!

Kyle
 

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I think that is totally awesome! Good call on the Walnut veneer; looks really nice and bracing is good. Mounting the sub facing up is a novel idea. You don't have kids, do you? That bouncing cone will make a fine trampoline for action figures and Matchbox cars. :eek:


I see you're using a flared port; was that from PE? Is the end inside the box flared too? How did you come up with the design/port length? WinISD? What are you powering it with? We always have questions around here. :D
 

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Looks nice. Tempted to have my next coffee table like this too
 

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Great job, it looks awesome.:cool:
 

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I have seen some sub up builds before [I have a 6 & 9 yr old so I'm not that brave,] but I'm am into the large flange mounts on the risers. Those are just inverted threaded pipe mounts?
 

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Very cool build! Nice work.
 

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Discussion Starter #9
I see you're using a flared port; was that from PE? Is the end inside the box flared too? How did you come up with the design/port length? WinISD? What are you powering it with? We always have questions around here. :D
No kids for me... Well except for the roomates (Which are sometimes worse).

But yes, the port is from PE. It's the 3" flared port and yes, both ends are flared. I got the port length from Bassbox, but there was a small slip of paper that came with the port that had instructions for how to calculate it by hand.

I was hoping no one would ask what I'm powering it with because that is BY FAR the worst part of this. It is mostly a temporary fix until the summer when I will be working and have a bit more money lying around. I am using a measly 100W Dayton plate amp. Since the sub is much more powerful than the amp, I made a little rig to help keep it from overheating using a quiet little computer fan and some scrap plywood.




Definitely not the best but it's getting the job done.
 

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I was hoping no one would ask what I'm powering it with...
IMG
Definitely not the best but it's getting the job done.
Hahah, awesome!

I love the design of this, and am very impressed with the overall look, especially since the driver is upfiring!

How is the glass mounted to the pipes on top? Surely it can't be held down by gravity alone, otherwise I imagine it would shake like crazy. I may be wrong though.

Excellent work!
 

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Thanks for the details on your build and your ingenuity shows with your amp-cooling solution. :D I used a car audio amp powered off a 12v DC benchtop power supply for about 2 years back when change between the sofa cushions was scarce. You use what you have, and that's what you're doing. *thumbsup*
 

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Very nice looking enclosure! You said the enclosure is 5 cu ft. (net internal?) and is tuned to 18hz correct? and you're only using a single 3" round port? Not to burst your bubble, but I'm thinking once you get a larger amp and start to crank the volume you are going to run into some pretty serious port noise...

With the parameters I listed above and 100w power, you will be hitting a peak port velocity of almost 40m/s. Ideally you want port velocity to be below 17m/s. Once you apply more power the velocity will only increase further...

Also, do you have a HPF in place?
 

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Discussion Starter #16
I'm thinking once you get a larger amp and start to crank the volume you are going to run into some pretty serious port noise...

Also, do you have a HPF in place?
You're probably right on the port velocity... I guess I don't have everything figured out yet (I'm only 20! :p). Definitely something I'll have to take into consideration in the future. Thanks for the heads up!

And as for a HPF, I didn't build my own, I'm just using the one that is built into the amp!
 

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You're probably right on the port velocity... I guess I don't have everything figured out yet (I'm only 20! ). Definitely something I'll have to take into consideration in the future. Thanks for the heads up!

And as for a HPF, I didn't build my own, I'm just using the one that is built into the amp!
Yea, you live and learn. If possible I would modify the table and add at least 1 more 3" port if not 2. You will need to make each one of them longer if you add more but they should still fit just fine. Let us know is you want it modeled with the additional ports.

Sent from my Galaxy S5 using Tapatalk!
 

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nicely done.
 
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