Anikun07's SLA Builds

[anikun07]

Oh, I see, I misread your post. For some reason I was thinking you didn't glue them together and just attached them to the cab.

[Ian Westwood]

Just a quick heads up for you.... and it looks like you'll just get away with it... but I allowed a little extra at each end of the baffle so that the speakers didn't hit the side of the box. Have you figured that bit out OK?

[anikun07]

Thanks, Ian. I haven't gotten that far yet. That part will come next. I wanted to make the baffle before I built the cab so I could be sure that it wouldn't be too small when I was ready to mount the baffle and drivers.

So I've got the two straight baffles cut and they're just sitting on top of their cabs.




And I glued two of the curved SLA pairs together. Soon the baffle will be one piece and the cab can be built for it.

[Disco-inferno]

nice work

[Ian Westwood]

Starting to come together nicely! I can almost hear them from here

[anikun07]

Is the listed crossover calculator in the instructions, http://www.diyaudioandvideo.com/Calculator/XOver/, the same calculator for figuring out a high pass filter? I don't know that I will put a high pass filter on these SLAs, but for my next build I probably will so I'd like to know more for future reference than for immediate use. The listed schematic listed shows the HP filter at 120 Hz, but if I were to install one I think I'd prefer 80 or 90 Hz.

[anikun07]

I glued the last baffle piece last night and it was all set for measuring and cutting it's cab. I didn't tighten the long clamps much, just enough to keep the baffle pieces from sliding apart. I thought if I tightened them too much they might have forced the pieces to dry at an unwanted angle.




I pre-assembled all the pieces. It will be just under 30 1/2" wide. I also decided to make it 9" deep, so it's not too wide and it will have plenty of room for the drivers to fit.



I decided I wanted the back to be the removable piece so I put a frame inside for it to attach to.





I mitered the inside pieces and screwed them in place from the outside, then applied PL Premium (my speaker glue of choice). Then I removed the back piece so it wouldn't become a permanent side.

[lancemhorsley]

nice job! The curved sla looks like it went together perfect!

[LelandCrooks]

Nicely done.

[anikun07]

Thank you, guys.

[anikun07]

Before I glued the center SLA together, I meant to cut the grooves for the side woofers. So I had to do it after. Before I glued I checked where the woofer magnets touched the side piece on an piece of scrap and marked it. I transferred over the marked area to my cab and drew a rectangle. I used a power multi-tool saw blade to cut the lines and then a chisel and mallet to knock the area out. I took out about one ply of the wood. Then I used the multi-tool sander to smooth out the grooves.



Then I finished gluing the center SLA. I put the baffle in place and traced the back edge of it so I would know where to put the PL Premium bead.




Then I clamped it and let it dry.




I got my first crossover done and will post pictures of it later. I tested it and it worked but I later realized a bit of solder was connecting bridging to areas of the PC Board, but I think it should work fine with that bit removed. I replicated Ian's boards in his SLA post. Thanks, Ian!

[anikun07]

Here are the pictures of my crossovers. I followed Ian's method and used the Parts Express crossover boards. They changed the plating to a silver instead of copper, otherwise they're the same.




They're labelled so I know which crossover goes to which speaker. The curved SLA needed a slightly different component layout than the straight because the large capacitor. I also followed Ian's advice and used zip ties to keep the heavy coils in place on the board.




I'm not very good at soldering but each joint seemed pretty solid when I was done. If it wasn't, I reheated the solder to make it so. It seemed that flux helped a bit too, to get a good solder joint on the board. Maybe it's the solder iron tip I used but the solder always just wants to flow back to the iron and stay on one side of the component leg. Any tips? Since I'll be soldering the speaker wire to the terminals and suggestions would be much apprectiated. I think I will strip the speaker wires mid length and solder it to the terminal. I think this might be easier than trying to solder two wire ends to each terminal.

[Drey Chennells]

A sticky joint requires clean surfaces. High heat makes a fast solder and less heat transfer, the smaller gauge metals the less heat needed.

Coat each surface that will be soldered with flux. I just get a good bit on my fingertips and pinch/roll.

Use a high gauge, thin rosin core solder and tin each surface.

I usually place the tip in between the surfaces (ahem) for quickest heat transfer, melt and move tip to wire and stay til each wire strand coats.

Test joint with a good tug.

[anikun07]

Thanks Drey.

Is there a minimum proximity the crossover caps or coils can be to the woofer magents? It's a slightly tight fit, but if I place the crossover on the bottom of the cab near the woofers, nothing touches but it's a little close. I think there's maybe 1/2" at most between components. Is that alright? I didn't know if the magnetic fields affected each other and if it would even matter.

[Ian Westwood]

Thanks Drey.

Is there a minimum proximity the crossover caps or coils can be to the woofer magents? It's a slightly tight fit, but if I place the crossover on the bottom of the cab near the woofers, nothing touches but it's a little close. I think there's maybe 1/2" at most between components. Is that alright? I didn't know if the magnetic fields affected each other and if it would even matter.

Caps can go anywhere but you have to be mindful of coil placement. Here's an interesting article http://www.troelsgravesen.dk/coils.htm scroll to the bottom for the tl;dr summary.