Taking the sonosub plunge! Take two! (1 Viewer)

[Patrick Sun]

ThomasW, thanks for the note on driver placement. I still might leave them on top of each other.
Ed P from the HTT suggested I route out some material on the backside of the endcaps between the t-nuts to increase the back wave pressure (of course, I don't really have room to do this but on one side of the drivers given where the holes were cut into the endcaps). Will this adversely affect the sound quality if I leave things as is?
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[Patrick Sun]

You guys must think I'm really really slow. I made progress, but I'm not quite finished. Here's what happened today:
Photo 69 - I realized I needed to somehow figure out a way to keep the top Shiva driver's cables near that driver, so I used the bracing inside and tapped in some nails to make a "loop" to thread the cables through and keep them near the top of the sub.
Photo 70 - This gives you a view of the use of the bracing as a cable hook. I took the braces out at this time as I start to pop in the top endcap. I finally figured out that the easiest way to get the bracing poles into position is to put the top endcap in first, and then put liquid nails on the top and bottom of the bracing poles. Then slide the poles through the top driver hole and into position.
Photo 71 - Here I applied some glue on the insides of the the sonotube just before I put in the top endcap.
Photo 72 - Start popping in the top endcap. I had to sand down the sides again to get it to fit just right - this took lots of time.
Photo 73 - I finally get the endcap into the sonotube.
Photo 74 - As described earlier, I get the sonotube on its feet, and apply liquid nails on both ends of a bracing pole and feed it through the top driver hole and get it situated just right.
Photo 75 - Here's a close-up of both bracing poles installed.
Photo 76 - Once the bracing poles are in place, I applied some downward pressure on the top endcap to make it flush with the sonotube. There's a 1/16" of extra sonotube material that needs to be shaved off soon.
Photo 77 - I caulk the top endcap where it meets the sonotube on top.
Photo 78 - I tack in nails to keep the top endcap in place.
Photo 79 - I start what I call "Blind Man Caulking" as I caulk the inside of the top endcap to make it airtight as possible.
Photo 80 - I finally finish caulking the inside top endcap after trip on the bottom side to see what still needed caulking. This was also time consuming.
Photo 81 - Since there's extra sonotube material, I start sanding down the sonotube. This was also time consuming and I'm sure my neighbors appreciated the sanding sounds nearly 11 p.m. tonight.
Photo 82 - I finally finish sanding down the sonotube flush with the top endcap, more or less. I try filling in the sonotube's slight opendings in its fiber composition with glue to make the sonotube smoother.
Photo 83 - I finally get to spray paint the top endcap once again. I'm letting it dry overnight, and will apply a clear coat tomorrow.
So that's it for tonight (I squeeze in mowing the grass too).
What up for tomorrow:
1. Sand down the paint if needed, repaint, apply clear coat.
2. Connect the bottom Shiva driver voice coils to the
correct cable, and screw in the driver to the bottom endcap.
3. Connect the top Shiva driver voice coils to the correct cable, and screw in the driver to the top endcap.
4. Move the sonosub into the home theater, test for leaks, and have some HT fun.
5. Then fix the outer appearance with the cloth.
I'm fairly confident I'll have the sub up and running by tomorrow night!
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[ThomasW]

Pat
The metal basket of the Shiva is actually pretty deep 1.25" from the back of the mounting flange to the start of the basket openings. I don't believe that there will be any problem with the backwave being hindered by the thickness of the endcaps. But if you need something extra to do in your spare time, use a file to bevel the area between the "T-nuts". This will insure the least resistance for the rear wave.

 

[TerryC]

Wow!
After seeing the pictures of the caulking I highly doubt you're gonna have any air leaks.
Terry

 

[Patrick Sun]

My gawd! This sonosub building is absolutely addictive! I skipped dinner last night and didn't even realize it! Since it took me a while to sand down the sonotube edges, I was lost in fiber dust. I noticed that the fiberboard had little arc-ing gaps in it, so I puttied in some Elmer's glue, and after building it up, that filled in the gaps nicely. Then I spray painted just a little too ernestly and somehow the paint congealed into cobwebs, and that was 3 a.m. last night. So the alarm clock goes off this morning around 6:30 a.m., and I immediately take my morning nature call, and then slip on the slippers and head back into the garage. I had to do more sanding to buff out all the cobwebs on the top endcap surface. But I got it a lot smoother, and I judiciously used the spray paint like an airbrush, being careful not to loaded up any one area and that seems to prevent anymore cobwebs from forming. Then after some breakfast, I applied one coat of clear acrylic coat to the top endcap before going into work. Whew!
The sub should be done tonight.
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[Patrick Sun]

I now have a functional Sonosub! I finished up around 10 p.m. tonight. I'm so tired. But here I am to update the rest of the story:
I get home and notice some more bumps on the top endcap, so I sand them down, apply some more spray paint, and then a clear coat. Finally I ran out of spray paint, so it was a good time to stop with the top endcap finishing for now. Then I was ready to put in the bottom Shiva driver.

I can't wait to give it a workout tomorrow night! Stay tuned for the qualitative evaluation, and some SPL numbers if I get a chance soon.
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[Ty Zucker]

Nice job Patrick. I'm sure the documentation of your exploits will be helpful to others building their own sub.
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[Danny R]

Can't wait to hear it for myself sometime.
Your documentation is probably the most extensive I've seen thus far. Please add it to your webpage as soon as you get a chance (and admins should probably archive this thread).

 

[Stacey_V]

Patrick...
Kudos to you for your Sonosub efforts! This is the best "how-to" for those interested in DIY sub making. When possible, PLEASE provide a detailed analysis of how this baby sounds. Compare it to your previous Shiva sub, and let us know how those DTS tracks sound! I am envious that yours is now done, and mine is still on the drawing board.

I am still trying to figure out the best sized enclosure, tune, etc. for my single Shiva tube. I look forward to starting my own project, and hearing the end result.
Many thanks for your efforts!
Stacey

 

[Joseph Millison]

Pl@,
Congratz on your great "SunoSub"! It looks awesome, and probably sounds even better! You did a killer job documenting everything as well, way better than I had tried to do. You should definitely make a complete how to page I think it would help those people who want to make a SonoSub, but don't quite know where to begin yet
Awesome job!
J6P
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Do not taunt Happy Fun Ball.

 

[Jason J]

So Pat,
what are the actual dimensions of your sub? I believe you said the tube was 54.5" tall overall, and I'm assuming your endcaps are each 1.75" thick, so does that give a net internal height of 51"? And what about the port? How long did it end up being? Thanks!
Jason

 

[Patrick Sun]

Jason, the internal height discounting the endcaps is roughly 50.75" (I sanded away a smidge (1/16" to 1/8") of the sonotube when I put in the top endcap supported by the internal bracing poles, and the plywood I used wound up being slightly thicker than 1/4", maybe 3/8" thick - but this is all pretty negligible once you get to nearest integer of the sonotube length). The 8" port wound up being 24" in length (flush to the bottom endcap).
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[brentl]

Patrick "that's one BIG sub!"
Ok 2 questions
Aren't you worried about the speaker wire on the lower sub touching the cone??
Haven't you ever heard of Robertson Screws ?? Just kidding I know you amarcans don't like new things(kidding) but get your hands on a Robertson bit and some screws and there is nothing like it.
It's just a square headed screw, almost impossible to strip if you get the right size of bit(unlike the Philips). Lets not talk about the worst....the flat head UGH!
Brent L
WOW!

 

[Patrick Sun]

Brentl, why thank you very much.

The wires would be hard pressed to be hitting the cone (there's a metal basket), plus the wires would vibrate off the backside of the driver pretty quickly with the right songs being played at moderate levels.
The Robinson screws sound like a good idea. If I need to take out the driver, I will look into at least getting some philips head screws, if not the Robinson screws. Thanks for the suggestion.
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[Seungsoo Hwang]

Great job. I will most likely be using this thread and its extensive pictures to help me on my tube. Kinda scares me that my sub with one 15" is just about has big as your tube with the two shivas. Let us know of the sound.

 

[Danny R]

So all in all how much did this thing hit your wallet?

 

[Patrick Sun]

Danny, once I tally up the Home Depot receipts (after I return some extra stuff), I'll figure out how much I spent on it. I may leave out the 4 power tools since I consider that to be amortized as the years roll on.
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