[tremrej65]

Hi,
I'm about to start the build of a Double Trouble sub.
I was thinking of changing the shape a little bit. I would keep the same main measurements. The recommended cabinet is mainly two squares tube of 13 inches (inside). I would make it with two round cylinder of 13 inches (inside) instead. See attached drawing.
Question: will it change its performance?
Here's the sub by itself:



I could also make a bracket to mount a speaker on top of it:



Any feedback are welcome.
Rejean

[Charles Xavier]

Interesting design but I am curious what material you would use to make the cabinet.

[tremrej65]

Interesting design but I am curious what material you would use to make the cabinet.

My plan is to stack 18 layers of 3/4 MDF (1" for the center baffle) cutout with a router, ideally I would cut them with a CNC, but I don't have one yet (seriously thinking about building a lowRiderV4). I would make a templates from 1/4 MDF or plywood to go around with the router.
We'll see. The design is still a work in progress... We'll see.

[jmimac351]

My plan is to stack 18 layers of 3/4 MDF (1" for the center baffle) cutout with a router, ideally I would cut them with a CNC, but I don't have one yet (seriously thinking about building a lowRiderV4). I would make a templates from 1/4 MDF or plywood to go around with the router.
We'll see. The design is still a work in progress... We'll see.

Yup.

[tremrej65]

Wow. These speakers are gorgeous. Plywood instead of MDF. I like it.
Do you really need the steel rod? I was thinking of using wood dowel to help with the alignment during the gluing.

[jmimac351]

Wow. These speakers are gorgeous. Plywood instead of MDF. I like it.
Do you really need the steel rod? I was thinking of using wood dowel to help with the alignment during the gluing.

Not mine.

I am a complete woodworking novice, but I would probably glue / screw to the finished layer and use a flush trim bit to match the current layer being worked to the finished layer.  Keep doing that until big enough.  Then the outside layers are just glued on.

Maybe that's a really bad idea. 

[Early B.]

While you're at it, make two pairs and add a 14x16 top plate on mine.

[KTS]

I like it, I am not sure how it would change it sonically. It would look unique with a good veneer. How will you isolate the top speaker from the sub? Instead of a bracket you could flat top it to give a place to mount/isolate the top speaker.

[jmimac351]

Make similar tubes for the woofer / tweeter.  I would just make the woofer sealed.  Send just that portion to Danny and Hobbs and let them tweak the crossover.  Won't cost much to ship. 

[corndog71]

I thought about building very similar double trouble cabinets.  But I ended up with the regular cabinets.  It was just easier.  The rounded cabinets would’ve been much much harder.

[tremrej65]

I thought about building very similar double trouble cabinets.  But I ended up with the regular cabinets.  It was just easier.  The rounded cabinets would’ve been much much harder.

That's the route I'm taking: I'll first build a regular cabinet (square) with the first kit I'll received tomorrow. Then I'll work on the rounded version, and possibly buy a second kit for the rounded version. Having two different sub will allow me to A/B them. Then if the rounded one sounds as good as the regular one, I'll build a second rounded one to replace the square one. You get the idea.
As for the finish, I'm not decided yet. I've never used veneer before. I think I'll have to simplify the design to make it easier to apply the veneer: the concave area between the two woofers seem impossible to put veneer. An alternative is to use plywood instead of MDF and give it a tinted varnish finish. I also like a good painted finish, but obtaining a super nice surface will be difficult I think. Work in progress.

[tremrej65]

Here's some progress on my rounded version of Double Trouble sub.
First, a question:
Should I round the face (and the back)? Is it important for these frequencies (below 100 Hz)? I would not go more than 1/4". If not necessary I would not to.

I ended up with 20 layers of MDF: 19 of 3/4", 1 of 1/4" (to make the baffle 1").
I made a template which I use with a flush bit on the router. It worked pretty well. About 10 hours to cut all the ribs.











I glued the ribs 4 at a time:



Then lots of sanding (100 grid):



That's where I am: two coat of primer (Bulleyes 1-2-3):



Next step: more primer, paint and make a base.
That's it for now.
Have a good day.

[jmimac351]

NICE!!!!!   

[Early B.]

This is the greatest thread in the history of Audiocircle!

[KTS]

This is the greatest thread in the history of Audiocircle!

Agreed! 

[goggle1824]

This is the greatest thread in the history of Audiocircle!

Ahhh… I see what you did there. 

[Bill Baker]

Very sharp. How much time do you think you’ll have in it in the end? I probably missed it but what finish are you putting on it?

[czechm8]

That's fabulous work!

[Peter J]

What a novel idea! Good on you for thinking of things in a different way.  I'm anxious to see the end result.

[jmimac351]

This is going to turn out great.  These could end up as statement / furniture pieces.

Imagine them with different types of wood... the sky is the limit for what they could be built to look like.

And... these could be sealed subs, just as easily.

Thanks for going for it.