[billy lane]

I have to force mine too , i usually just log off. It looks like you have a good plan .

 

[chrapladm]

So your going to seal this sub to your exterior wall and then just have a vent covering it up?

How deep is the vent?

You also need to make sure it is sealed properly or it will rattle a LOT. Also dont want too big of a depth on your speaker's cone and vent because then your loosely building a 6th order design. Not a big deal but just let it be known is all.

 

[Drifte]

So your going to seal this sub to your exterior wall and then just have a vent covering it up?

How deep is the vent?

You also need to make sure it is sealed properly or it will rattle a LOT. Also dont want too big of a depth on your speaker's cone and vent because then your loosely building a 6th order design. Not a big deal but just let it be known is all.

The vents Ive looked at are just 1/2" cold air return covers. Designed to just cut the drywall out and stick in. Their will definitely be some work involved securing it to the wall and not rattling. The speaker cone will be 4" from the vent (the thickness of the wall).

Right now Im trying to model it with round ports so I can use nice flared aeroports. I think I can manage 2 4" ports, 23 m/s peak velocity at 17hz. I think thats within range? Going to check box volume again and re-model with 2 round ports in sketchup. Looks good in winisd.

 

[Drifte]

Im actually seeing nice output with a 23hz tune, it keeps excursion down, but at 20hz (109db) its down almost 4db. However it has nice a nice gain at everything about that idk..its definitely not flat. Port velocity is in the 30 m/s range.

Notes for my own reference:

19hz tuning reduces cone excursion at 27hz (the peak excursion frequency) 15mm (peak measuring 14mm, claimed 16m capable)

19hz tune 111db at 20hz
18hz tune 110.7db at 20hz

19hz tune down 2.7db at 20hz
18hz tune down 3db at 20hz (16mm excursion around 27hz)

With these findings I started looking at a 20hz tune. Not much is lost or gained but port velocity is up and excursion and output remain similar to 19hz.

17hz tune port velocity is way down 16.8 m/s @ 20hz, excursion is back up though to 16mm

 

[Drifte]

Before I finalize anything, Im wondering if I should put feet on the bottom of the box or just lay it flat on the floor? Idk which would be better in this situation.

 

[Drifte]

Progress on the box. Im trying to decide now if I should make a large brace in the middle, or dowel brace the box. This is the largest box Ive built without using MDF, so its a little different to me. Front baffle when finished will have a second layer of 1/2" oak hopefully making it more sturdy.

10.5cf, still undecided on the ports and tuning but getting there.

 

[chrapladm]

As long as you have ample bracing you should be fine. Window, dowels or waffle style is fine. Just make sure to brace well is all. The more inert the cabinet the less the cabinet will move or vibrate against the wall.

 

[Drifte]

19hz model results:

Taking any advice I can get on choosing the tuning frequency.

 

[billy lane]

I believe you are in the best box size and tuning range . Have you decided on a bracing pattern ?

 

[Drifte]

I believe you are in the best box size and tuning range . Have you decided on a bracing pattern ?

I have not. If it was a regular box arrangement it would already be braced and done. But Im building the box at my dads wood shop rather than my garage. So I had to stop and come back and double check the placement inline with the wall studs.


dowels work, but i prefer the look and overall contact a full cutout brace can create.

 

[Drifte]

Back from a trip to the mountains and my parts are in. Its time to finish the box and add the ports etc.

These ports make a 15" woofer look pretty small.

Measuring the parts to fit taking into account the wall studs.

 

[Drifte]

Picked up the 16x25" vent. I have some work to do there to make it look right on the wall, but you can get an idea of how this will look now.

grill on

And some grill cloth will be attached to that so it should hide well.

 

[billy lane]

What mountains did you go to ? It looks like you have things moving along and in a good direction . I also like the lime green level .

 

[Drifte]

What mountains did you go to ? It looks like you have things moving along and in a good direction . I also like the lime green level .

Thanks, spent a few days in Keystone snowboarding.

Finally took a cat ride to the highest point and was definitely worth the effort.

 

[billy lane]

The snowy trees sure are perty aint they ! How high is that ?

 

[Drifte]

The cat took us to 12.3' el. Its noticbly colder and windier (with a lack of trees) at that point.

I was up at 14' el. this summer after hiking mt. Huron, that was a killer view. I have this picture taken of Mt.Huron as my desktop on the computer. Its cool to see I would have been a little dot on the peak of the mountian.

 

[billy lane]

So now that you are back down to earth how is your sub project coming along ? Have you made a plan on keeping sub isolated from wall ?

 

[Drifte]

Well, Im hoping something as simple as some thick adhesive backed foam will do the job. And I can push the box up against the wall with that foam kind of sealing the box to the wall but not transferring vibrations.

 

[billy lane]

I was thinking the same thing .

 

[Drifte]

Managed a few hours of work in on the enclosure this weekend. My dad enjoys wood working so I came back to the shop and saw he had some creative bracing put together. It would do the job so I went with it and continued the build.

Im still using a jigsaw to cut out circles, but Ive been doing it for so long I dont mind.

Driver and ports test fit

Test fit with the second layer of the baffle to give the woofer a recessed look. The enclosure is 3/4", this second layer is 1/2" to match the subs frame. The ports also received a slight recess into the 1/2" which is just one layer off the ply.

Everything glued and nailed in here for bracing.

After those pics I ran a bead of caulking sealant around everything inside.

And thats where I had to stop, the wood puddy on the outside had to dry before sanding and stain. Then I will attach the front 1/2" cover which I may be doing in a satin black (undecided). I dont know if it shows, but i took the router around the front recess as well for the driver to give a smoother look.