$325 Lab 12 based PA tapped horn ~ 35Hz extension

I cut the angle I like using titebond wood glue for my builds so the angles need to be pretty spot on, unlike when using a urethane glue from a tube, which gives you more flexibility.

That being said, I forget what the angle was. When you initially cut off the board, leave that one longer so you can do the final angle cut on it after, without making the board too short.
 
got both cabs almost built, one just needs the last side panel on.

Quick questions:

1. I messed up on one of the openings for the driver, its a little big in some areas and when I lined it up on the face, I could see light in some areas where the bolt holes were. Should I just seal the ring with some caulking around the entire edge, or can I make a new ring out of 1/4" and put it between the cutout in the panel and the sub to assure a good fit, or will this cause issues since the driver is now 1/4" more away from the original mounting location?

2. When joining the last side panel on my build, one of the interior panels may have slipped a bit as I was standing on the panel to make sure I had a tight bond, but I felt the whole thing moving a bit. When I looked in through the speaker opening I saw the panel that goes straight up behind the woofer face, had come out slightly from the wood. I screwed it back down but am concerned other panels may be slightly loose that I can't see inside. Is there something I can pour inside the cabinet to seal up any cracks that may be there now?
 
Things like that are why horns aren't really considers an "easy build"

That said, with each build they get better as you gain experience.

Honestly, if there is an air leak at the throat, it will become a huge issue. For something like this (the large hole, not enough wood for the screws to grab into and securely hold down the driver) it may be worth the $100 to start with new wood and start over. Also, panels must be air tight throughout the path length of the horn in order for it to work well.

Did you follow the construction technique that I linked to on the first post? I posted it to make the build go smoothly for others as well as share my experience (learning from my mistakes)
 
Hi loudsubz,

I second everything mRgSr says in #196.

As to your question in Post #195: "...can I make a new ring out of 1/4" and put it between the cutout in the panel and the sub to assure a good fit, or will this cause issues since the driver is now 1/4" more away from the original mounting location?..."

You could mount your driver to a 3/4" thick mounting ring with sunk in t-nuts from the back, and then glue the ring into the box, I don't think the acoustic performance would be hurt. You could also make up for the increased cross-sectional area at S2 by glueing 3/4" discs through the driver hole against board "G" (search for "cone correction"). The slight reduction @ S4 should not make any real difference.

But, you have a tested design, so I would recommend not to alter it any more than necessary.

Regards,
 
Things like that are why horns aren't really considers an "easy build"

That said, with each build they get better as you gain experience.

Honestly, if there is an air leak at the throat, it will become a huge issue. For something like this (the large hole, not enough wood for the screws to grab into and securely hold down the driver) it may be worth the $100 to start with new wood and start over. Also, panels must be air tight throughout the path length of the horn in order for it to work well.

Did you follow the construction technique that I linked to on the first post? I posted it to make the build go smoothly for others as well as share my experience (learning from my mistakes)

I have followed the plans and also know from building multiple bfm cabs the proper way to assemble them, but that still doesn't make me weary when putting the last panel on. I will have to test it and see maybe its ok
Can
 
some more updates:

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


the one im a bit concerned about is the last hole. I had my buddy cut it out and I think he should have used a circle cutter as there is some flat spots on it. I may just make another 3/4" space out of wood and mount it on top of the hole and run my t nuts under it.
 
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An externally hosted image should be here but it was not working when we last tested it.


the one im a bit concerned about is the last hole. I had my buddy cut it out and I think he should have used a circle cutter as there is some flat spots on it. I may just make another 3/4" space out of wood and mount it on top of the hole and run my t nuts under it.

Ugh, that cutout is horrible. Was your buddy a bit tipsy when he did that? :)

It is very important that there be no leaks in that location in a TH as any that exist can make quite a bit of difference in the low frequency output. The spacer sounds like a good idea to me.