Otop Jarray build x 4

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himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#46 Post by himhimself »

Handle backers...
Attachments
15588831013531651296048969801256.jpg
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#47 Post by himhimself »

All 32 of those stupid bracket t-nuts are now glued in. Second guessing if I'll actually use them, but there in. Seems like I spent a lot of time on that one little item.
I have a bunch of 3/8" 7-ply baltic planks I rescued from shipping crates, so I laminated 1" strips around the rear of the cabinets. It will give some extra meat for when I round over the edges and also make the cabinet look a bit beefier. I plan to do the same on the front, although maybe with just 1/4" since it's already going to be tight to fit the tweeter arrays. We'll see. I did the same thing on the fronts of my t30s to make the 1/2" panels look more substantial. I like the cabinets to be light, but to look and sound HEAVY :lol:
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#48 Post by himhimself »

Couple pics...
Attachments
Thicker edge
Thicker edge
Tee nut
Tee nut
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#49 Post by himhimself »

Got the backs cut out of 1/4" ply today, as well as the braces. Might swiss cheese the braces to knock out a little weight. I need to find my 2" hole saw to make the cutouts for the speakon jacks. Also got the flanges glued in on one cab. Tested my driver and it fits without having to do the half-moon cut.
I'll pick up a stick of quarter round tomorrow to reinforce the inside of the edges from the sheath braces to the rear of the cab so I can round over with a 3"8 bit. Since I left the full sides on the braces the front part of the cab is already fully reinforced.
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#50 Post by himhimself »

Quarter round reinforcement pl'd in place.
Attachments
15590885009655404018516973425466.jpg
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#51 Post by himhimself »

Actually wasn't legit quarter round, but I didn't have time to stop by Menards today, so scrounged around the garage and found a stick of old half round moulding that I sliced down the middle. Whatever works...
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#52 Post by himhimself »

A little mod to the back braces that will support the x-overs. They are kind of heavy since I put hp and lp on one board and I was a little concerned about all that weight hanging off a thin plywood joint. These little scraps should keep everything nice and secure even if the cab gets dropped on its side.
Third cab's rear flanges are curing now...
Attachments
15592653859205980215865680860703.jpg
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#53 Post by himhimself »

Continuing to take baby steps. Finished up the backs except for drilling the mounting holes. Nothing interferes with the drivers - had a little worry there for a minute.
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#54 Post by himhimself »

Couple pics of the back
Attachments
15594847087374182476855122864761.jpg
15594845890184527175875070098488.jpg
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#55 Post by himhimself »

Strips added to the front of the straight array cabs. Looks better to my eye than the 1/4" edge. I can slip the arrays in with about 1/4" of clearance. Will need to experiment some with the melded cabs since the tweets take up more space, plus they need to be turned sideways a little to fit the drivers between the mounts.
Attachments
15595127148836302874058689364731.jpg
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#56 Post by himhimself »

Got the strips fitted and glued to the front of the two melded cabs - there's just enough room to finesse the melded arrays in and onto the mounts. Drilled the pilot holes for the speakon jacks. That's going to be it for the weekend. Hopefully will have some time one or two evenings this week to keep moving forward. Feels like the end is finally is sight.
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

67baja
Posts: 931
Joined: Sat Dec 11, 2010 12:10 am
Location: Las Vegas, NV

Re: Otop Jarray build x 4

#57 Post by 67baja »

Coming along nicely. Can't wait to read your review of the Otops.
2 THTs, 2 TLAH, SLA curved, 1 8-AT, 1 AT JBL 1002D, 4 Otop12s, Jack 12, TT with Eminence 10", 2 SLAs, 1 T30 slim, 2 T30s (2-10" each), SLA Pros, TrT.

CoronaOperator
Posts: 1648
Joined: Wed Mar 25, 2009 7:07 pm
Location: Medicine Hat, Alberta, Canada

Re: Otop Jarray build x 4

#58 Post by CoronaOperator »

Very nice work!
Built:
17" width 10" driver Autotuba
2 x 29" width dual Lab12 Tuba60
6 x DR250 2510/asd1001
In progress:
2 x DR250 2510/asd1001
For best results, point the loud end of the array towards the audience

himhimself
Posts: 599
Joined: Fri Nov 13, 2015 9:34 pm
Location: Vancouver BC & Bloomington IN

Re: Otop Jarray build x 4

#59 Post by himhimself »

Me too, baja. Thanks CO. And Bill, you've guilted me into finishing July 4 2019!
Rounded over all the edges with a 3/8" bit. Had a couple little tear outs that I had to patch with some PL. Sanded down the patches this morning and they look pretty good.
I marked the spots for the back mounting screws, drilled them as well as into the cab flanges, then rough sanded them. Then back to my trusty pail of Duratex. That stuff is the BOMB. For any of you that haven't used it, there is no better way to finish your cabs. I gave a quick flat black spray to the backs, painted on the Duratex, then rolled the finish with a texture roller. I've found it takes barely any and is much easier to cover if you paint the stuff on with a brush first, then roll it rather than trying to roll it on directly. Also makes the roller much easier to clean up.
Once the backs dry, next step will be to mount the speakons and crossover and wire them up, and glue on the convoluted foam. Then they will be ready to go.
As for the cabs themselves, I still need to get the mounting pieces for the grill cut and attached. Also need to final trim the foam plugs and make sure there's no driver slap. Then it should be mostly final assembly and finishing...
2xT30 (20", 3012LF)
2xT30 (21", 3012LF)
4xOtop J-array (Beta12, melded/straight piezos)
Truck Tuba (MCM)
Next up: 2xJack12 or family of table tubas

Bruce Weldy
Posts: 8301
Joined: Fri Nov 27, 2009 11:37 am
Location: New Braunfels, TX

Re: Otop Jarray build x 4

#60 Post by Bruce Weldy »

himhimself wrote: Sat Jun 08, 2019 9:40 am if you paint the stuff on with a brush first, then roll it rather than trying to roll it on directly. Also makes the roller much easier to clean up.
Are you using the spray grade Duratex? I don't see how you could paint on the roller grade with a brush. It's so thick, seems like it would gum up a brush and be a mess. The spray on is thinner and can probably be brushed....

I use the little rollers that Leland sells. You can just dip it in the pail and it comes out without a single drip. Rolls on great.

Either way - I agree that Duratex is amazing stuff, however you get it to stick.

6 - T39 3012LF
4 - OT12 2512
1 - T24
1 - SLA Pro
2 - XF210


"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."

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