BillFitzmaurice.info

I'm finally getting around to building a pair of DR200's. I've wanted to to years, just never seem to find time. Now i'm making time.

Our local Menards got BB scraps, varying in size from 19.5" to 23" square. I got a pile about 20x20, 6.99 per board, then %11 off that with a rebate. They are decent 7 equal ply pieces, although I had to pick through the pile to get the best. There are a few with patches on one side or small knots but i'm working around the couple I had to settle with. I was able to cut my tops and bottoms, sides and back all out of nice pieces with no patches or knots. I've cut the driver baffles in rough size. I'm laying out the curves and cutting the buttcheeks just now before I broke for some lunch.

Oh thos buttcheeks are a stinker. I tried to use my RotoZip and a circle template to make a few passes around 1/8 deep or less. I busted 2 bits and burned the wood one got so dull. I finally gave up and roughed thiem with a jig saw. Then I went back with a router and another circle template and cleaned them up as best I could. Nothing a little PL won't fill but what a pain. I'm starting to thing the whole build difficulty is based on those dang humps.

OH the dang images, i'm too stupid for this web interface...

A RotoZip doesn't have the capacity for that job. PL is like a Papal Indulgence. It forgives a lot of sins.

looking good HowieZ!

howiez wrote: ↑Sat Nov 06, 2021 2:14 pmI'm laying out the curves and cutting the buttcheeks just now before I broke for some lunch.

Oh thos buttcheeks are a stinker.

What has been seen, cannot be unseen

I got a pile of the BB squares from Me'nards years ago. Still have about a dozen. I wonder if they'll work for this JBL 18" I have laying around?........

Yep, those Menards BB squares are awesome. I still have a few left after buying out my local store when they let them go at $1.99 a piece. I see they have them back in stock again, but the price has definitely gone up a bit.

Didn't get much done today, too much yardwork to do with the unseasonably nice weather.

I really struggled wrapping my head around the throat angles. I should have just taken at face value Bills quote, PL forgives...

I made a 10degree bed to lay my horn sides on, and then cut them on a miter saw to get that compound cut. And i have a compound miter, but I had making those cuts

Then the sides you'll see I just cut oversize squares, glued and nailed them. Then I clamped them to my saw overnight to cure square/flat whatever. Then I just ran them trough the table saw at 10degress to clean the sides off. They are glueing overnight now to the rear spacers/braces and i'll clean those up with a 3deg cut to size.

Finally able to do a little more.
I've cutout my octogon woofer spacer.
I'm using a GRS 8PT-8 woofer for my build.

I've gotten my horn throats and spacers glued up overnight clamped flat to help with warp.
They lay nice and flat on my table saw, i'm happy .

Next I mocked up the whole outer shell to get the woofer baffle and horn throat lined up/square.
Once I had them in a decent location, I pinned the baffle to the throat with three quick 18ga nails.
Then I laid them flat and clamped them a bit to shoot a few more pins in them.
I can lay either 3degree taper on my table saw and they all sit flat, very pleased with this, when most of my woodwork is like snow skis!

Last recent progress, i used a cleat per Bill's plans to get the baffle/spacer on the line, square to the bottom then top.
I glued and nailed one at a time, bottom first, 3 tacks to get close then stood it up removed the cleat and a few more nails.
Then I repeated with the top, cleat for square/alignment, a couple pins to hold, then stood her up and shot a few more.
Next I put this woofer baffle/horn throat/spacer assembly in the cabinet mockup again to ensure square as the PL cures.
I put one clamp in the buttcheek crack to hold the top/bottom to the sub assembly.
Then I laid the face down on my saw table, laid the sides against it, and used a band clamp to snug it up.
Then I checked square on all 4 corners, cab one is perfect, cab two is a bit of a parallelogram.
So I put a clamp on diagonal and persueded her into square.

Looking great! Thanks for the progress reports.

I'm completely enjoying this thread. Thanks for sharing the journey Howie!

The driver you're using tickles me a little. For the most part, it looks to be within spec. The Qts is a little high at 0.55, where the plans specify an acceptable range of 0.20-0.40. I'll be curious what affect that has on the overall cab performance. If it's reasonably close to the desired sensitivity, a $20ish 8' driver in a $80ish cab that's able to outperform the majority of the typical12"-15" commercially available offerings on 25% (or even less) of the required power... just the thought puts a devilish grin on my face.

There are two concerns with the GRS 8PT-8. One is the high Qts, which will result in less sensitivity than the Beta 8. The other is the lack of rising response in the mids, so the midrange response won't be as good. It still should work pretty well with sufficient EQ.

Yes, i'm also a bit concerned about the driver, but I was willing to take a $20 gampble. I really hunted for Beta8 or Alpha8, whichever was the 'original' design, but they appear to be discontinued or out of stock everywhere. My next choice was actually a Dayton Audio that looks near identical and has similar specs, just a bit more wattage. In my case, this gets me off the ground cheap. I'm literally building these for my personal home use. They will live in my garage 360 days a year. If they sound Ok, they'll be used at my son's wedding by our friend of the family DJ next summer. And who knows, by then, I may have swapped out the drivers for some Eminence after all.