View Full Version : [Bandpass] How does this look?
Kangaroux
06-10-2012, 01:32 PM
4th order BP for 2 obsidian 12's. Gonna be running them off of 1800-2500w (1800w for daily 2500w for burps). Box is roughly 2.1 cube sealed (1.05 per sub) and 6.9 ported (or ~3.5 per sub). Port is 101.5 in^2 tuned to 40hz and uses a 4" kerf to help against any port noise. I didn't like how close the subs were to the port so I put in some big 45's to help prevent any dead zones. The setup is NOT built for competing, just going for a loud daily. The box will also be braced with several pieces of 1/2" threaded rod.
There's a typo on the sealed section, it's supposed to say 2.1 not 1.05.
http://i.imgur.com/1nHp7.png
wenn_du_weinst
06-10-2012, 02:18 PM
I think it may be pretty boomy actually.
The_Grimy_One
06-10-2012, 02:19 PM
Any idea what bandwidth this should play?
galacticmonkey
06-10-2012, 02:44 PM
Yeah, Id shrink the port and the ported chamber.
Shoot for around 2 cubes sealed after displacement, then build the ported chamber around 3-4 cubes with a 55-65in^ port. For my listening preferences, I do like a 40hz port. With those size chambers and small port, you should have response down into the teens and up to around 60-65hz.
How loud are you trying to be?
SuperSaeYoung
06-10-2012, 03:55 PM
I've always wonder how do you put and take out the subs?
05trailblazer
06-10-2012, 03:56 PM
^^ when bulding them you put them in first then seal it off. common sense.
I've always wonder how do you put and take out the subs?
If you don't have an access panel or have a port large enough to crawl through, then you put them in there and hope for the best.
SuperSaeYoung
06-10-2012, 04:02 PM
If you don't have an access panel or have a port large enough to crawl through, then you put them in there and hope for the best.
I would love to see pics or vids of this!
DBBOOM
06-10-2012, 04:07 PM
Gonna be boomy/peaky with the ported side that large. 4 - 5 cubes would prolly give better music range.
I would love to see pics or vids of this!
Sent you a pm :)
wenn_du_weinst
06-10-2012, 04:18 PM
I did a little math and right now you have a pretty good burp box at 40hz.
Kangaroux
06-10-2012, 06:21 PM
This is basically the same box I have for my current 12 just scaled up. It's peaky but on the lows at around 33-34hz. Cabin gain evens out my response pretty well. If I had to aim for a frequency response I would say 25-45hz. My current box is 1 cube sealed 2.8 ported with 50 in^2 of port tuned to 40 and I like how it sounds
Kangaroux
06-10-2012, 06:25 PM
Now that I think about it, I like how it sounds at around 2.8 ported. I might do 5.5-6 ported instead. No point in trying to tweak it only to find out I don't like it and have just gone through 2 sheets of wood
wenn_du_weinst
06-10-2012, 06:41 PM
when I looked it wanted ported to be smaller then the sealed section to play flat.
Kangaroux
06-10-2012, 07:32 PM
when I looked it wanted ported to be smaller then the sealed section to play flat.
Yeah that's the same thing I got but this is peaky enough on the lows and my cabin gain is heavy enough to even it out pretty well.