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View Full Version : MA15 Mounting Kit?



jnewmark
11-15-2009, 07:17 AM
I pulled out my old JBL brochure I got with my E140's 20 years ago, and was reading something about this kit to simplfy front mounting. What exactly did this kit do and is it still available? One of my problems with retrofitting E140's to newer bass cabs is that the rounded edge on the back of the mounting frame of the E140, makes the speaker too large by a smidge to front load without having to enlarge the circumference of the existing mounting hole of the cab. Would this kit be the answer to that?

grumpy
11-15-2009, 11:43 AM
No.
Clamps put the frame in the same hole.

Uncle Paul
11-15-2009, 11:44 AM
The MA-15 is four clamps and some cork gaskets. The clamps screw to the baffle and hold the speaker captive. I haven't used one in a long time, but I think it used machine screws and t-nuts behind the baffle.

jnewmark
11-15-2009, 12:03 PM
Thanks. Any suggestions for front mounting an E140 in a cab who's cutout is just a smidge too small? I've resorted to a sabre saw and tried to eyeball it, but I'm not very good at.

lgvenable
11-15-2009, 01:11 PM
or a router where you mount a cut-out fiiler board in the hole, and then carefully re-rout to the correct size, but using a homemade router template. Look up how to rout a round hole on google; only difference is you have to re-fill the wrong size hole with a replacement, and essentially start again. The MA15 kits are still available from JBL.

jnewmark
11-15-2009, 02:32 PM
So, if I'm understanding this right, I could use an MA15 kit to front mount an E140 OVER a smaller cut hole, and it is held on by clamps? Obviously, the speaker would be extended out more that way and may come into contact with the grill? I do have a Dremel tool, but did'nt think it was powerfull enough to rout a thick baffle, such as the ones found in most bass cabs.

cohearent
11-15-2009, 02:45 PM
The MA15 kit consisted of 4 cast clamps for front mounting JBL drivers. I don't know if JBL still makes them. The last time I bought a couple sets they were ridiculously expensive. There are several other similar clamps from other manufacturers that can be used successfully. EV being one. The main issue is the size of the "step" from baffle to the top of the frame.

lgvenable
11-15-2009, 03:24 PM
mount over a hole, no, not unless you fill the hole with a ring you rout, and glue in a backer mdf ring perhaps; then mount flush. A lot of work that way.

Alternately if you're like me, I had to either dremel or sand off a little on the edges of my 2245 to fit in a tight fitting 2245 frames into a slightly too small hole.
I sanded with a home made jog to make sure I sanded at a tangent/perpendicular to the edge of the frame. It didn't take much; and I only did that by building a jig to cover the cone with 1/4" plywood, and sealing the rear with painters tape completely; so no metal filings can spoil a drivers day.

I used a belt sander in a vise, and a lazy susan to turn the speaker slowly as I evenly sanded the edge (with a 400 belt). Then I painted the edge with black Krylon, you'd never know I sanded it if you looked at the raw speaker.

see the result, which is mounted in a routed hole in the cabinet face.

Uncle Paul
11-15-2009, 03:26 PM
So, if I'm understanding this right, I could use an MA15 kit to front mount an E140 OVER a smaller cut hole, and it is held on by clamps? Obviously, the speaker would be extended out more that way and may come into contact with the grill? I do have a Dremel tool, but did'nt think it was powerfull enough to rout a thick baffle, such as the ones found in most bass cabs.

No, the speaker still has to be able to seat into the baffle. The MA-15 allows you to change out drivers more quickly, because you only have 4 bolts to loosen as opposed to every mounting hole in the frame. It also looks cooler, at least to me.

You can see 5 clamps used on this picture, normally 4 are used on 15" drivers, and 8 on 18"ers. http://www.lansingheritage.org/images/jbl/specs/pro-speakers/1997-4344mkII/page1.jpg

jnewmark
11-15-2009, 03:39 PM
No, the speaker still has to be able to seat into the baffle. The MA-15 allows you to change out drivers more quickly, because you only have 4 bolts to loosen as opposed to every mounting hole in the frame. It also looks cooler, at least to me.

You can see 5 clamps used on this picture, normally 4 are used on 15" drivers, and 8 on 18"ers. http://www.lansingheritage.org/images/jbl/specs/pro-speakers/1997-4344mkII/page1.jpg

Ok, I see what you mean. I actually used something like this on round speaker grills to keep the grills in place. Looks like I got to get the old Dremel tool out.

lgvenable
11-15-2009, 06:11 PM
the MA15 mount would be superior. When I built my sub, the tightness of the hole was a surprise. I might add, that a newer 2245H; went into the hole w/o any issues; while the older one I had reconed fits much tighter.

If you've already routed, then my method of sanding the tangent of the edge will quickly resolve your problem in twenty to thirty minutes. Painters tape to seal the rear make sure everything comes off easily. You'll find that it takes longer to setup and test the fit than to sand the edge by a factor of ten.