Even More on that Speaker Box

This speaker box has become quite the project. I swear, if I look back on the number of hours I've spent on this thing, it will rival the hours spent rebuilding the front end of the MGB. Anyway, more progress to update.

Baffling

testing only-angled idea

In my last post about the speaker box, I mentioned adding in some extra support along the edges. I'm sure it was helpful, but when I thought about how much air would be moving around the inside of the box, I got concerned about how the sub-woofer speaker would have air-influence over the 6x9's and vice-versa unless I created some kind of barrier between them. I had initially planned to do that, but this project has lingered on for months now, so I had almost abandoned it. I had some time and some left over materials, so I constructed a couple interior walls to isolate the 3 speakers from each other.

wiring cup

I initially thought about something simple: one wall per side that ran at an angle from the rear wall to the front wall. There's a dark picture to the right that shows what that would have looked like. This would have been easier, but consumed a lot of air space that probably should be available to the sub-woofer. To maximize the air space available to the sub-woofer, I changed to an an angled wall from the front face back parallel to the 6x9 speaker angle until it was clear of the rear of the 6x9 speaker magnet (this was about 3-1/2" long by just over 9-1/2" tall). I connected a wall from that point parallel to the rear/front walls to the side. This left little excess air-space for the 6x9, but the sub needs all the air volume I could bring it in this small box. As it is now, I am at the low-end of the air volume recommended by the manufacturer.

Cutting and Fitting

baffle glue drying

With the walls cut with an old-skool hand saw (I make crap-cuts with power tools), I shifted to test-fitting. The extra supports in the corners required cut-outs in the baffles. You can sort of see the square-ish cut outs in the corners in the picture on the right. The left-side baffle wall fit perfectly though the right side did not. From this, I discovered that some of my early work was not 100% square/perfect. So, some additional trimming was needed on the right side. Still, things looked good so I drilled one hole per baffle to hold the 2 pieces together and glued them.

To support the inner wall baffles, I took a couple small pieces of cut-off left-overs and placed a support along each of the inside of outer walls. I was able to rest the parallel-to-rear-wall baffle against this support to hold it straight as well as for an extra surface for glue.

Shaping
I had planned for 3 wire cups on the right side of the box. I bought these cups from Crutchfield, and used a hole-saw to mount them. The orientation of these cups becomes interesting when we consider the interior baffles I'd just built. I had 2 cups set side-by-side for the left and right 6x9 speakers and one below it for the sub. You can just make out the left-side hole in the picture below. This speaker cup orientation seemed intuitive. Once the baffle was set in place, wiring into the cups will be compromised. So, I had to pull out the Dremel again, and shave down a gentle curve behind 2 of the cups so there would not be any pressure on the wiring once all the various pieces were together.

smoothing the edges

With the baffles shaped, I glued them into the box. Once the glue had dried overnight, I assessed the gaps, and plugged them with wooden kabob skewers... and more glue. Basically, I determined the length of the gap, and cut a thin skewer to length. I then squeezed the skewer with pliers until it was thin enough to fit into the gap. With a thin slotted screwdriver, I pushed the filler material into the seam, and repeated until the gap was completely filled with wood and then slathered it with glue. I then ran a thin bead of glue along every seam to make sure the 5 sides and the baffles were sealed.

At this point, I decided to fix the misaligned outer edges with the Dremel and a hand planer. Ideally, it would have lined up perfectly. If I build another box, I'll take much more care to align just one hole per side for the screw, so the sides fit much better. I did that with the inner baffles, and they aligned far better. Anyway, after a bunch of hours with the Dremel and hand planer, the wall mate-points are smooth enough where I think it will be hard to see how out-of-alignment they are once covered with carpet. That's what I'll do for next time... as well as get some wiring in, and the 6th side of the box attached... and then the edges planed.... yeah, this project got a little out of hand. But it keeps me distracted without pulling a car off the road.

Thanks, as always, for following along.