How to design a simple Sealed speaker enclosure

I discuss how to plan the shape of an enclosure, as well as how to determine the size and shape of the material the box is constructed with. Following on from Part 1: • Design a Speaker enclo...
Timestamps:
0:00 - Introduction
1:55 - Tip 1- Decimetres
2:31 - Plan the shape of the box
2:52 - Does the sub fit?
5:03 - Tip 2- Material efficiency
5:52 - Outside dimensions
7:51 - Cutting list
9:27 - Tip 3 - Plywood
10:29 - How to mark cuts on a sheet of wood
12:29 - Tip 4 - What to do with extra wood?
14:22 - Conclusion

[@Dakoustics]

I know this one took a while to get out, as the saying goes: Life happens when you least expect it. I had the video 90% done as of uploading the previous part, and was expecting to have it out in a week rather than a month. Hopefully it'll be worth the wait. Part 4 is already done, part 3 requires some more editing. Should be up soon, fingers crossed.

[@nebulous962]

Thanks for the guide :)

[@nebulous962]

10:00 where does fiberglass fit on this example? I am thinking about building box from fiberglass

[@Dakoustics]

Ok, fibreglass is either fantastic or terrible. For a start, material stiffness is relative to thickness cubed. So, something twice as thick is 8x stiffer. Not a ton stronger, but the stiffness is what holds the air pressure in. Fibreglass, even 4 layers, isn't particularly stiff. The hull of a boat, or a surfboard get its stiffness instead from the curves, which can be a good thing. Fibreglass can do tight curves much better than plywood, so a combination of plywood for large, flat sides, and fibreglass for tight corners are an ideal match. For a wholly fibreglass box, it'll need either curves in its geometry, even where a flat surface is needed, such as the bubbles on the 2008 Beijing Olympic pool, or a ton of reinforcement. Purely creating an enclosure with flat sides would need such a thickness of fibreglass, it'd be expensive, and take ages to build the layers. Another option could be to purchase fibreglass reinforced panelling for the spans. So in summary, fibreglass can't really fit into this example, as wood is really easy to get right, but fibreglass can either be fantastic or a literal flop depending on how its shaped.

[@nebulous962]

@@Dakoustics okay :) thank you :)

[@fredbradshaw3835]

Did you say mounting inverted is less professional? Why do you feel that way, just curious.

[@Dakoustics]

Main reason is it looks cleaner, and its more likely a professional installer would install standard unless the magnet looks cool. Also keeps cables out of sight.

[@fredbradshaw3835]

@@Dakoustics good reason, not really big on inverting. Two reasons to do so: cooling factor, tends to stay cooler and like u said, if the motor and mag is badass.

[@tajouriezzeddine545]

please tell me what is the used software I'm in beginning

[@Kennystarfighter909]

WinISD

[@budgetaudiophile6048]

Pause . . .I just want to say that I just built a new enclosure for my theater . . .128 cubic feet gross. 49 x 48 x 97! It houses 6 18s. I cut the wattage from 19200 to 4800 due to the new excursion. It's sealed for now, but I'm considering adding a vent to it and setting the tune to 10Hz. . . . Okay, now back to the video.

[@Dakoustics]

holy crap, that's almost 4 cubic metres! 600L/sub, twice the volume of the mazda box, per sub, I feel like I can safely say your box shouldn't be choking those subs LMFAO If you ported it at 10Hz and gave it the full monty I'm honestly not sure what would happen, it's out of the realm of predictability That's absolutely mental, full 4x8 sheets of plywood?

[@budgetaudiophile6048]

​@@Dakoustics Unfortunately, I went with your arch nemesis . . .MDF. 3/4 inch. After watching this vid (I kinda wish I watched this video FIRST) I am starting to wish I went with plywood! It would have been FAR less messy. The dust that MDF creates is absurd and so hard to clean up. And a lot lighter! I used 5 sheets of 8 foot x 4 foot MDF, so that + bracing + subs, this thing probably weighs 400 pounds or about 200kg. For bracing I went with 3, 8 foot (2.4m), 4 inch x 4 inch housing beams. Yep, the same beams that keep your attic from becoming part of your basement. I just cut them down to size, bolted them to the chassis, and sealed them with liquid nails. I learned though that I absolutely SUCK at building boxes and version 2 of this monster will absolutely be plywood and I'll pay someone to cut it and bolt it together for me. I tried my absolute best and took my time with everything and there are still flaws that I see. It's sealed nice and tight but it's not "perfect".

[@Dakoustics]

@@budgetaudiophile6048 For a box that size, I dont blame you for finding it a pain in the ass, including the beam it's virtually a house within a house, but yeah ply probably would've made things a bit simpler. Still tons of dust, working on folded horn 2 right now. Did you assemble it inside and take it in sheet by sheet?

[@budgetaudiophile6048]

@@Dakoustics I can't wait to see the videos of your folded horn project! I love watching your builds come to light! It's so entertaining! So the theater is a pretty big room at 1200 sq feet, 111sq meters according to Google. So the box itself is right at home, unfortunately the opening to the room is narrow so I had to split the boards into two pieces, then do that annoying thing where you stitch and seal them back into one. That's another reason I went crazy with additional bracing. For the driver cutouts, I did all of that outside (well in my garage because it was 18 degrees F or -7C) then brought them downstairs. I think the only addition I'm going to do for Version 1.5 is add an additional baffle to the front, just because. Version 2 will be double baffled from the get go.

[@creektilghman9187]

Splendidly to see Woodprix have new plans which helped me save some money and energy for this construction.