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View Full Version : Does it matter where I mount the sub on a ported box?



cheeto
01-27-2008, 05:59 PM
sorry to make a whole new topic about this, but I really need it answered. I'm building a ported box, and I'm gonna put the sub facing the same way as the port (on the same board). Does it matter where I mount it on the remaining space? I mean of course not over the port or anything stupid like that, but should it be centered, far away from the port, what?

JimJ
01-27-2008, 06:01 PM
Whatever works cosmetically for you.

cheeto
01-27-2008, 06:02 PM
Whatever works cosmetically for you.

Awesome. Thanks a lot.

cheeto
01-27-2008, 07:42 PM
Another quick question - is this piece necessary? (see picture)

hilighted in red


http://img176.imageshack.us/img176/3381/portpieceqx7.png

What's it even for? I've seen it done on a few boxes, does it just help the sq? or what?

I didn't calculate for it in my port stuff, so it'd probly mess the tune of it up, idk.

ken72988
01-27-2008, 08:52 PM
I'd like to know what that piece does too..

i think it just helps the air flow and or helps deflect the soundwaves out the port better

BrianChia
01-27-2008, 09:13 PM
It's not necessary but it does help. You'll be OK if you don't use it.

cheeto
01-27-2008, 10:19 PM
Ok. I drilled the holes for the bottom and top pieces to the box.
I have another question.

Do I have to drill holes on the top and bottom of the vertical mdf pieces that go between the top and bottom pieces too? Pretty weird way to say that, but it's the only way I can think to say it.

BTW, here's the box I'm making. Should be perfect with the sd2.515 I bought.

http://img175.imageshack.us/img175/3882/boxyo2.png

Tehgregzor
01-27-2008, 10:26 PM
Well i was gonna say bracing, but that's a pretty solid box. I guess its the same reason some coat the inside with resin...eliminate all the resistance you can, to gain more output.

cheeto
01-27-2008, 10:30 PM
Well i was gonna say bracing, but that's a pretty solid box. I guess its the same reason some coat the inside with resin...eliminate all the resistance you can, to gain more output.

That's what I was thinking, helps the air flow out. The only thing is - do I have to make a calculation for the size of it? The port frequency was calculated without it.

IDSkoT
01-27-2008, 11:11 PM
I'm pretty sure it's just a 45 degree angle cut that helps disolve 'port noise' which is basically air knocking against 90 degree angles.
It's not necessary, but it helps.

And, I think to calculate it, you just see the smallest piece you can put up against it so that it flows smoothly. The area inside of the port shouldn't be too different, not enough audibly.
But I've never done it, this is just from what I think / read.

MyFartsStink
01-27-2008, 11:14 PM
That's what I was thinking, helps the air flow out. The only thing is - do I have to make a calculation for the size of it? The port frequency was calculated without it.

it counts the port displacement, but I dont think it would count for brace, and subwoofer displacement.

MyFartsStink
01-27-2008, 11:17 PM
the angle brace just helps out the hot spots that happen in the box. Someone please correct me if im wrong. Other than that its just added support to strengthen the box

cheeto
01-28-2008, 05:16 PM
Ok, that's what I was thinking about that angle piece. I'll make one in a few minutes... But I still have another question about technique. How do you line the holes up between the pieces in the box? I don't have clamps, so I think its gonna be a ***** to do. So far, I just took the top and bottom pieces, put them on top of each other and smushed em in a corner, and drilled holes through both. I tried to be exact, but it's not all the way uniform.

What's the easiest way to transfer this onto the other pieces? Oh, and what's the best way to hold everything in place while I'm trying to work with it?

Idk if that makes sense but yeah

cheeto
01-29-2008, 07:49 PM
Bump. I really need to figure this out.

BuckyBoy
01-29-2008, 10:37 PM
Ok, that's what I was thinking about that angle piece. I'll make one in a few minutes... But I still have another question about technique. How do you line the holes up between the pieces in the box? I don't have clamps, so I think its gonna be a ***** to do. So far, I just took the top and bottom pieces, put them on top of each other and smushed em in a corner, and drilled holes through both. I tried to be exact, but it's not all the way uniform.

What's the easiest way to transfer this onto the other pieces? Oh, and what's the best way to hold everything in place while I'm trying to work with it?

Idk if that makes sense but yeah

:confused:

You glue whatever pieces you are connecting together, drill a hole, then put a screw in it. Is that what you are talking about?

MyFartsStink
01-29-2008, 10:45 PM
screw or nail em together bro. start with bottem and sides, hang one end off the table and glue the piece on that end and nail or screw from the bottem and so on until you get it done.

cheeto
01-29-2008, 11:23 PM
screw or nail em together bro. start with bottem and sides, hang one end off the table and glue the piece on that end and nail or screw from the bottem and so on until you get it done.

Yeah I got that much. I'm comin off real nooby in these posts, I don't know much about enclosures. I pre drilled all the holes yesterday for the top and bottom, then realized that the back panel and one port piece needed it too.

The question is do I have to pre drill holes into the side of the MDF too? I'd imagine so, but if I don't, it'd save me a hell of a lot of work.

I mean like this - __|__

| represents the drill bit
and _ represents the side of mdf, the 3/4th inch part.

I just wanna get this straight, the cost of one sheet of MDF and dealing with the douche at lowes was enough for me haha

MyFartsStink
01-30-2008, 12:48 AM
pics?

cheeto
01-30-2008, 08:01 AM
pics?

Um. Here :o

When I drew this I realized how dumb my question actually was.

http://img245.imageshack.us/img245/7717/titsbg7.png

BrianChia
01-30-2008, 08:07 AM
Yes, you should predrill the sides/edges of the boards too, or they will split. But you should drill through both pieces at the same time so the holes will line up. Just line it up real good the first time, drill a hole carefully, then put a screw in (doesn't have to be tight). Then you can drill all the other holes once the two pieces are lined up and attached.

BrianChia
01-30-2008, 08:07 AM
Sweet drawing by the way. :)

dbman150
01-30-2008, 08:21 AM
all i can say is wow lol

cheeto
01-30-2008, 04:48 PM
all i can say is wow lol

Yeah I kinda came to my senses after I asked the question the first time haha.

Btw the woooo on the drill represents the sound it makes

WOOOOO