1st BFM build: 2 X Omni 15 TallBoy in 2-12 configuration

[aeolos]

draehn! I like it! Now we need a front view (thanks for tolerance Bill):

The Omni 15 BigBoy in the 4-12 configuration . Would that thump or what?
--aeolos

Readers please note: this IS NOT a real photograph of a real cabinet, nor does it depict an actual Bill Fitzmaurice cabinet design. We havin' fun is all.

Although I must say, looking at it, it's interesting .

[David Raehn]

How about an Omnibus Top 480?

[aeolos]

draehn, that one (or something like it) might even work, although I defer to Bill on it. It would have sufficient internal volume looks like.

Very neat
--aeolos

[David Raehn]

Another old saying that follows me around: "The only thing sexier than the sound of a radial engine..... is two of them."

No need to try to reinvent Bill's wheel. If I need something that big and loud I'll stick to the recommended 280s or 300s. Stacks of them.

Enough fiddling for me.... Let us know how you clearance your drivers.

[aeolos]

Radial engines, man oh man. There used to be a guy with an AT-6 who brought the plane out over our neighborhood on weekends and spent afternoons doing aerobatics. At first I loved it, but after a while that roar lost its appeal. But I know what you mean: an engine with authority. Eventually the neighborhood got so built up that he moved his operations farther out from town.

And you are right: leave design to those who know how, or put in the time required to learn how. Now I say that after myself tweaking Bill's Omni 15 TallBoy a little bit...

Will be going with the approach shown in the original photos, although the pieces connecting the brace to its stubs at top and bottom will be jigsaw-cut with curves like those in old-timery "spanners."

Photos when done, not sure when I'll be able to get to it though.

Best
--aeolos

[aeolos]

The fix operation begins. First, the extensions to move the brace back 2.5":

Cutting the old-and-in-the-way brace out:

more shortly
--aeolos

[aeolos]

draehn, I adopted your suggestion for a simpler fix than the one originally proposed. Many thanks!

Readers please note: these ARE real photographs of a real cabinet, that diverges slightly from Bill Fitzmaurice's Omni 15 TallBoy design... but only by a little bit.

The camera on this Samsung Galaxy Note II introduces a lot of pincushion and other lens distortion that resists easy correction, but such correction as was easily performed has been done.

Photographs of the dry fit for the fix to the "I mounted the vertical brace incorrectly and so could not fit the speakers in the cabinet" issue:

(at increasing closeup)

and a photograph that I like just as a photograph

Was in a tearing hurry as usual, so some of the screws could have been better aligned for visual appeal, but functionally this fix gets it done and is structurally sound.

In fact I like it so much that I'm going to build it into the second cabinet as well. Makes plenty of room for the woofers and doesn't take long to implement, once you've got the pattern for the brace extensions, or whatever you want to call them, those curvy things .

Now back to work work, and eventually to complete this cabinet (and someday the other one too, that will go much faster of course). Getting close to turning the first cabinet on, hard to take time to earn a living with this left undone, but oh well.

Will of course post photos with the parts PL'd together and sanded down when possible.

best
--aeolos

[miked]

Those are some fine-looking curvy-brace-extension-mover-things! Seriously, those are cool-looking! Great job on figuring out a fix.
PL'em in there and move forward! Good luck!

[David Raehn]

Great to see a reasonable fix.. Great job!

[LelandCrooks]

Nice recovery. It looks good too.

[aeolos]

Thanks miked, draehn, and Leland: your encouragement and good advice really help, and I appreciate it.

Milestone: the first cabinet is major-woodwork-complete ! Vertical brace fix glued&screwed, all holes filled (and I really like auto-body filler for that job, it sets fast and hard, thanks Bill), external sanding through 220 grit complete. Have cut the baffle restrictor plate but not yet installed it, need to put in the T-nuts for that and for the 12" steel grilles for the woofers, and run one more PL fillet along one seam between the lower woofer horn brace and the side of the cab, and it will be ready for finishing/cladding.

Today's photographs:

and one more pic, bb won't let me put it in this message...

--aeolos

[aeolos]

And the final photograph from today. Lots'o'pictures for a little Omni 15 TallBoy but maybe it will help somebody, somehow... perhaps to avoid my bonehead mistakes eh.

Closeup of the top brace-curly-thing-extender-pieces installed:

And that new vertical brace assembly is strong lemme tell ya. The whole cabinet is strong, as noted in the plans. DuraTex and Formica and aluminum and steel next. Then stuff it, and plug it in. Getting down to it, mighty fine, mighty fine.

Thanks again gentlemen
--aeolos

[Tom Smit]

Nice recovery. It looks good too.

+1

[miked]

And the final photograph from today. Lots'o'pictures for a little Omni 15 TallBoy but maybe it will help somebody, somehow... perhaps to avoid my bonehead mistakes eh.

Closeup of the top brace-curly-thing-extender-pieces installed:

newverticalbraceinstalled2.jpg

And that new vertical brace assembly is strong lemme tell ya. The whole cabinet is strong, as noted in the plans. DuraTex and Formica and aluminum and steel next. Then stuff it, and plug it in. Getting down to it, mighty fine, mighty fine.

Thanks again gentlemen
--aeolos

And you even filled in the screw holes on the BRACES that nobody will ever see. Wait until Bruce sees this picture. You have taken my OCD King title away from me, and for that, I thank you. LOL!

Seriously, GREAT JOB!!! With cabs, it's the end result that matters; not how you get there. If it has the required air volume and ports and drivers, doesn't leak and is well-braced, you have acheived your goal. Good on you for thinking through an "oops" and getting back on track.

Now; get back to work. I want to see some paint on that cab and those Metropolitan Museum Of Art Candidate crossovers installed!

[aeolos]

Yessir miked, it shall be done, and many thanks for your good words, with thanks to everybody else too. This will be a retro-style build, recalling those thrilling days of yesteryear when 2 other guys and I ran a little sound company. Really all I did was supply the money and was otherwise along for the ride, albeit supplying muscle as well when we deployed in various venues.

Our full-range cabs were factory JBL 4663s (Perkins bins with a very nice cast aluminum compression horn for midrange and a 2405 for tweet), 8 of them. We covered them in black slate Formica and put aluminum extrusion on the edges, and it did add much to their roadworthiness. Bottom end was some double 15" "sugar scoops" and some vast double 15" horns, those things were big. All factory JBL. Power amps, mix, and crossovers were all Yamaha with BGW for backup. None of us knew what we were doing, but by accident it sounded OK for its time. We could handle venues up to about 1,500 persons maybe. Got to meet some nice folks, and some real jerks as well.

Anyway, to recall the glories of the past, such as they were, these cabs will be covered in black matte Formica, with DuraTex on the front behind the main grille. Haven't decided whether to use cloth for the grille, already in hand (MelloTone) or get Penn-Elcom to make steel grilles. They make grilles of any size to order. I'd like to go with the steel but not sure the funding is there , and also not sure about the sonic transparency of the steel grid.

Then they'll have aluminum extrusion on the edges, and those big steel ball corners, probably the stackable ones, although I do not foresee ever stacking these things.

OCD you see, as miked pointed out. As for filling the holes in the braces, well, there were the holes, and there I was, and the goo was close to hand, so... why not? I didn't like the imprecision of the screw placement and thought filling the holes might help, and it did, a little bit, to my eye anyway.

Anybody have opinions about using polyurethane spar varnish on the inside of the cab? As a sometime dweller near salt water I always like to seal things up against humidity, so they don't start changing size and shape unpredictably. Are there any drawbacks to doing that, other than time and cost?

Thanks once again everyone, this is great fun, good occupational therapy too, and is teaching me a lot.

Best
--aeolos