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Old 02-05-2014, 06:44 PM
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"I will be interested to see how impactful these monsters are going to be."
Me too, chaluga!
The 316 project is ri-dunk-u-lous!!biggrin.gif
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Old 02-05-2014, 07:03 PM - Thread Starter
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Originally Posted by chalugadp View Post

Here is the drawing with measurements



Man this is going to be a beast cool.gif

So I've done a few re-measurements Donny and I have enough room to push these to 78" tall, otherwise 32" wide and 22" deep are still the other dimensions.
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Old 02-05-2014, 07:03 PM
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Old 02-05-2014, 07:04 PM
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Originally Posted by jbrown15 View Post

So I've done a few re-measurements Donny and I have enough room to push these to 78" tall, otherwise 32" wide and 22" deep are still the other dimensions.

They're going to rock being on that narrow of a base and having a driver that high in the air.

Also looking at the 3d model, you have 4 of the braces listed, but one will be a different size since it will not be up against the port. Keep an eye on that.

EDIT: 3 will be a different size, the size you listed doesn't account for the port.
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Old 02-05-2014, 07:07 PM - Thread Starter
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Originally Posted by notnyt View Post

They're going to rock being on that narrow of a base and having a driver that high in the air.

You think so? I talked to LTD02 about this when we were coming up with the design, he didn't seem too concerned about the cabinets rocking. We could also mount the drivers a little lower in the cabinets too, the bottom one could be mounted near the bottom and the top driver could be installed closer to the middle of the cabinets.
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Old 02-05-2014, 07:10 PM
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Originally Posted by jbrown15 View Post

You think so? I talked to LTD02 about this when we were coming up with the design, he didn't seem too concerned about the cabinets rocking. We could also mount the drivers a little lower in the cabinets too, the bottom one could be mounted near the bottom and the top driver could be installed closer to the middle of the cabinets.

My sealed boxes rocked with heavier drivers mounted lower in about the same depth of a cab. Did it impact sound? Who knows. I can almost guarantee you that those will in fact rock at higher excursion levels and low frequency.
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Old 02-05-2014, 08:19 PM
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My sealed boxes rocked with heavier drivers mounted lower in about the same depth of a cab. Did it impact sound?
It did. The driver creates sound by literally pushing and pulling against the air in front of the cone. If some of that energy is used to push the cabinet back and forth instead of pushing the air back and forth less sound is produced. If I was building a sub with two large drivers I'd make it dual opposed, which will eliminate any rocking and lost SPL.

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Old 02-05-2014, 08:20 PM
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Originally Posted by Bill Fitzmaurice View Post

It did. The driver creates sound by literally pushing and pulling against the air in front of the cone. If some of that energy is used to push the cabinet back and forth instead of pushing the air back and forth less sound is produced. If I was building a sub with two large drivers I'd make it dual opposed, which will eliminate any rocking and lost SPL.

True, but it's a sealed box and still creating the same amount of displacement/pressure change in the room.

EDIT: and yes, I know it affected the sound, but I meant to a noticeable degree.
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Old 02-05-2014, 08:36 PM
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Originally Posted by notnyt View Post

True, but it's a sealed box and still creating the same amount of displacement/pressure change in the room.

EDIT: and yes, I know it affected the sound, but I meant to a noticeable degree.
If the cone was moving back and forth by 15mm and the box was rocking back and forth by 3mm there'd be a fair amount of SPL loss.

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Old 02-05-2014, 08:41 PM
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Quote:
Originally Posted by notnyt View Post

Quote:
Originally Posted by jbrown15 View Post

So I've done a few re-measurements Donny and I have enough room to push these to 78" tall, otherwise 32" wide and 22" deep are still the other dimensions.

They're going to rock being on that narrow of a base and having a driver that high in the air.

Also looking at the 3d model, you have 4 of the braces listed, but one will be a different size since it will not be up against the port. Keep an eye on that.

EDIT: 3 will be a different size, the size you listed doesn't account for the port.

All four braces are the size listed. Me knows my way around sketchup cool.gif
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Old 02-05-2014, 08:42 PM
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Quote:
Originally Posted by chalugadp View Post

All four braces are the size listed. Me knows my way around sketchup cool.gif

How does that work if 3 braces go front to port, and one goes front to back?
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Old 02-05-2014, 08:45 PM
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There won't be any rocking except maybe in jbs theater by things other then subwoofers tongue.gif
Box will be attached to wall.
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Old 02-05-2014, 08:48 PM
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Originally Posted by chalugadp View Post

There won't be any rocking except maybe in jbs theater by things other then subwoofers tongue.gif
Box will be attached to wall.

Well, that will sure solve the problem. Hopefully those are some concrete walls smile.gif
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Old 02-05-2014, 08:50 PM
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Cool it's back! Do you guys have any plans to brace the top and bottom?. a couple dowels top to bottom?

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Old 02-05-2014, 08:57 PM
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Quote:
Originally Posted by notnyt View Post

Quote:
Originally Posted by chalugadp View Post

All four braces are the size listed. Me knows my way around sketchup cool.gif

How does that work if 3 braces go front to port, and one goes front to back?
Cuz all go front to port. I haven't included the 1 by 1 support braces . Only the plywood needed to be cut. The nice birch plywood jbs getting .
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Old 02-05-2014, 08:58 PM
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Originally Posted by steve nn View Post

Cool it's back! Do you guys have any plans to brace the top and bottom?. a couple dowels top to bottom?
Will be lots of vertical 1 by 1 support pieces. Jb is going to be cutting those by his bare hands cool.gif
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Old 02-05-2014, 09:00 PM
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Originally Posted by chalugadp View Post

Will be lots of vertical 1 by 1 support pieces. Jb is going to be cutting those by his bare hands cool.gif

cool.gif I want a vid of that lol. seriously!!

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Old 02-05-2014, 11:37 PM
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as for rocking, the reason that I wasn't concerned in this particular case is what I mentioned in post #2: the low ceiling joists could offer a method for bracing the cab. but then it was pointed out that the cabs could be bolted to the wall. so long as the wall is quite sturdy, that should solve that.

anyway, a question was asked about reconfiguring for two cabs again, with some additional limitations.

these would be about 38" tall, 32" wide, 22" deep. 3" slot port that is 40" long (one brace down the middle). net cab volume roughly 11 and change. tuning roughly 15-16hz.




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Old 02-05-2014, 11:59 PM - Thread Starter
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So with the cabinet now being smaller the port only needs to be 3" high?
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Old 02-06-2014, 06:58 PM
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Jbrown, you went off the deep end!! I likey smile.gif
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Old 02-06-2014, 06:59 PM - Thread Starter
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Jbrown, you went off the deep end!! I likey smile.gif

Bass you're back!!! Excellent.

Yes I have gone a little crazy!...lol
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Old 02-06-2014, 07:10 PM
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Quite impressive! eek.gif
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Yes I have gone a little crazy!...lol

Understatement of the new year!biggrin.gif
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Old 02-06-2014, 07:51 PM
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JB> Yes I have gone a little crazy!...lol




smilie_happy_053.gif

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Old 02-06-2014, 08:07 PM - Thread Starter
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smilie_happy_053.gif

LOL..... Steve you're always good for a laugh! haha

So I had to change the plans up a little after realizing how much of a pain in the a$$ it was going to be to get two monster subs into my basement with the only access by going threw the house. So I've decided on four large single ported cabinets. Each one will be 32" wide, 22" deep and 40" high.
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Old 02-06-2014, 08:44 PM
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Lol.. hey jb.. Yeah I saw that! 4 is going to be a job but with chals help and the tool situation it should work out just fine. It’ll help you out in other ways also like you just suggested. Heck you never know, maybe you’ll part them differently at some point.

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Old 02-06-2014, 09:04 PM
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Lol.. hey jb.. Yeah I saw that! 4 is going to be a job but with chals help and the tool situation it should work out just fine. It’ll help you out in other ways also like you just suggested. Heck you never know, maybe you’ll part them differently at some point.

Maybe he'll be fine with two and give me two of them cool.gif
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Old 02-06-2014, 09:29 PM - Thread Starter
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Maybe he'll be fine with two and give me two of them cool.gif


LOL.... I think best case scenario is I realize three is enough and give you the forth!..lol
So I'd have three and you'd have three.....lol smile.gif
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Old 02-06-2014, 09:35 PM
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Sounds good
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Old 02-06-2014, 10:01 PM
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"So with the cabinet now being smaller the port only needs to be 3" high?"

I was trying to figure out what you meant...yes. the cross sectional area of the port is on a 'per driver' basis.

3" x ~19" or whatever it works out to will be fine for each of these cabs which are loaded with one driver each.

if the cab size was doubled and the drivers were doubled, the port size cross sectional area would be double (it would be as if the two ports were simply combined into one big one).

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Old 02-06-2014, 10:05 PM
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in the monster cab, the port was going to be about 4" x 29" or so = 116 sq inches cross sectional area for two drivers.

in each of the smaller cabs, the port is going to be about 3" x 19" or so = 57 sq inches cross sectional area for one driver.

that is roughly the same amount of cross sectional area 'per driver' in both instances, thus they will perform pretty much the same from an air flow perspective.

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