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Discussion Starter #1 (Edited)
Ported enclosure advice needed!

I just pulled the trigger on a pair of CSS SDX15 subwoofers and a Behringer EP2500. The plan is to use them in two ~9-10 cubic foot boxes with an 17-18hz tune. Usage is 90% home theater/video games. The boxes will sit in the front of the room near the screen. Maximum dimensions for each box are 28" wide, 26" high, and 32" deep. The boxes will be made of MDF with a 6" sonotube port about 21" long. I know the subs are way overkill for my room size (11.5x13x8, roughly 1200cf) so I don't expect to ever drive them anywhere near 100%. :hsd: :dizzy:

I expect to use a front-facing or side-facing arrangement for build simplicity (down-firing is likely beyond my woodworking skills). A 15" sub in a 26x28 panel (or a 32x26 panel) leaves a lot of flexibility in the placement. Generally, should the driver be in the center of the panel? Toward the bottom or top? Side? :dontknow:

Should the port exit the box on the same face, or 90 degrees from the face, i.e. front-facing driver, side-facing port? I've read that the port should be at least one diameter away from another face, which should still leave some mounting flexibility. :scratch:

Thanks for your help! :bigsmile:
 

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Discussion Starter #3 (Edited)
The sub mounted towards the top and the port below it is a popular choice. You can mount the port on the side or back if you wish as long as it's not to close to a wall. As for your choice of twin SDX15's and a EP2500, you're in for a real treat!
I bet! All I've got is a 10" Titanic kit sub right now. :R
 

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Discussion Starter #4
I modeled up an enclosure using the maximum size I can get away with, which is 28w, 26h, and 32d. It looks like I'll end up around 10.3 cubic feet depending on how extensive the bracing is. The port will be 6", probably sonotube. A tune around 17hz seems to work out well in modeling. There will be two of these enclosures. Yes, the port will be hollow! :heehee: Sketchup is hard. :dumbcrazy:







Thoughts? :scratch:
 

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Looks good. Be aware the port air speed will be quite high if the subs are pushed. You should consider rounding over the ends.

http://www.subwoofer-builder.com/flares-10mm.htm

There is also the possibility the sub will bottom out because there is no high pass filter (subsonic filter) on the EP2500. Try the subs and see how they work, if you find that they do bottom out you'll have to add a HPF unit like the Reckhorn B1. It can also boost the input voltage to the amp if that's an issue with your setup.

http://www.creativesound.ca/details.php?model=B-1
 

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Discussion Starter #6
Looks good. Be aware the port air speed will be quite high if the subs are pushed. You should consider rounding over the ends.

http://www.subwoofer-builder.com/flares-10mm.htm

There is also the possibility the sub will bottom out because there is no high pass filter (subsonic filter) on the EP2500. Try the subs and see how they work, if you find that they do bottom out you'll have to add a HPF unit like the Reckhorn B1. It can also boost the input voltage to the amp if that's an issue with your setup.

http://www.creativesound.ca/details.php?model=B-1
Thanks, Mike! You're a helpful dude, and it is appreciated. I plan on rounding over both ends of the port, but I couldn't figure out how to do it in Sketchup :heehee:

Funny that you should mention the B-1. I was a little paranoid about bottoming the subs out so I placed an order for a Reckhorn B-1 from CSS earlier today. :spend: Chances are that I won't run them hot enough to cause problems, but better safe than sorry.

What a week! :spend: :spend: :spend:
 

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Discussion Starter #13
The port velocity will definitely be on the high side (around 30 m/s with a highpass filter in place at maximum power) but remember that I'm going with a pair of 10.3cf boxes in a pretty small room (11.5'x13'x8') so I don't expect to drive them anywhere near loud enough to have port noise be a big issue, and using dual 6" ports or an 8" port would complicate the build too much. It's a compromise I was willing to make because I don't think it'll be a real-world problem given my setup.

I've read your build thread and you've done some great work!
 

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hey thanks! I guess I may have been able to get away with one port but I'd like to be on the safe side for my first build. Anyway, it's just nice to think I'm not wasting my time with unnecessary portage...
 
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