Need help designing a home theater subwoofer

You may cut a round hole and double up the panel from the inside. That way you don't have the connector reaching out of the bottom that far. Be sure you can still grab and turn the Speakon mechanism.
Thought of that.
I’ve seen something like that
Love the square version.. the round seem...weird!
The round versions of Speakon were made to fit the holes for the Cannon/ITT or Amphenol EP series of connectors that had been in wide use since the 1970s, and dated back decades before.
Screen Shot 2023-11-09 at 11.23.18 AM.png

If you were used to seeing the connector side of Clair Brother's speakers for the last 49 years, the round versions would seem normal, and the hard to seal rectangular versions with only two screws would seem weird :)

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Did you happen to have seen the connector side of Clair brother speaker for the last 49 years?

Don’t know what “Cannon/ITT or Amphenol EP series” is.

But yeah, your round connector are nicer than my square in a round cut out mock up.
Four pole EP series speaker connectors (EP-4-14B and EP-4-13P) were depicted in post #266.
The EP series connectors preceded the Speakon connectors introduced in 1987 by many decades.
The Speakon connectors were competitors to the EP series, and have since been largely adopted for use as speaker connectors, while the more costly EP series requiring soldering the pins have fallen out of favor.

Here are the backs of Clair Brothers 12AM monitors, one with 4 pin EP panel mount connectors, another with the round Speakon equivalent, a NL4MPR.
Clair Brothers 12AM monitor.png

If you prefer the round Speakon over the rectangular, use the NL4MPR Speakon:

NL4MPR Speakon.png

The larger flange and two more screws on the round connector make an airtight seal easier to accomplish than the rectangular version.
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Nice build! With room gain and some DSP lift of the bottom end, you’re looking at an in room f3 in the teens. Enjoy!
Thanks! Let’s hope!

It’s my first home subwoofer build. And first I “designed” from scratch. (With the massive help of everyone). It’s reassuring to see your message and that all me effort will not be in vain.

I was thinking of using the damp in the behringer. Hopefully it will be enough.
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Here’s a quick recap of the work done this week and weekend.

I’ve made a couple of test using 3d printing to make a connector plate out of ABS.

Routed the hole for the connector under the subwoofer:


And decided to add screws to hold the finish cover plate on and complete the look.


Purchased different type of Adhesive to secure the connectors plate inside.

This is a sketch of how the plate in designed:

Two type of adhesive:
is there black pl adhesive - Google Search.png


Where I was thinking of putting the adhesive:

And glueing it from the inside.

Also, I have purchased speaker gasket. If I use the gasket, I could secure the plate with screws from the inside. Of the cabinet.

Not sure which one I’d be better using.
What you guys think?
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Thank you BP1 !

I’ve done my wire tonight.
Might be overkill, but they’re done!

Used 14 gauge wire. Ended each wire with ferrule. Than added and soldered terminal to connect to speakon inside the cabinet.

2 first cable I made, used 2x14 gauge, but then the ferrule was thiiiiiiis close not to enter in the subwoofer spring terminal so I used 1x 14gauge for the others wire.

Wrapped each of the in shipping foam and tesa tape. Heat shrink tube to finish them.

All that so they don’t rattle, in an sealed subwoofer 😅😂


Also, yesterday I glued in the magnet on the front baffle. And made a mistake. First 2 magnet went pretty well. Mixed epoxy and glued the first 2.

Then I mixed another small batch of epoxy and glued the 3rd and 4th magnet in the first baffle.

Then I told myself, to go accelerate the process, that I could mix epoxy to glue all 4 at the same time. Epoxy set to quick and one magnet was sitting proud.

So tried to sand it a bit. Didn’t make it.
Tried to: drill it, hammer it, hammer it with the claw side, screwing a self tapping screws. Nothing worked to get the magnet out. Tried applying heat. Burnt the wood on the surface a bit so I stopped.

Finally I cut the part and glue replace the part

When I got the clamp off, I drilled the hole for the magnet, and glued the new magnet in. I also filled the saw blade line.

Think I’ll have a couple hours to work on the subwoofer tomorrow as well.

Legs are in the making too.
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