Triple Ba 10.5LF Woof Box

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HoseHead
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Post by HoseHead »

Getting ready to close these up and try 'em out.

I understand the need to break up the standing waves inside the box. In the past, I've used batt insulation. I can get an unlimited amount of these foam shipping pads from the office - Cisco cards.
Do you think lining each cavity with these would accomplish a superior dampening effect?
Should I also line the cavity surface where the sub pokes in? - not that there's a whole lotta surface there.
Does the foam appreciatively affect the cavity volume? These are only .5 cuft (as recommended by BA) to start with.

Pix of mock up. Comments and suggestions are appreciated.
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stipud
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Post by stipud »

Looks perfect to me ;)
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oldskoolmseriesfan
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Post by oldskoolmseriesfan »

That looks good, very nice job. Just wondering where u got the acoustic foam from. I'm building a room downstairs for my son and his drums(he's 7 and already into music 8) ) That would work well on the walls and ceiling.Is it cheap?
VW337
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Post by VW337 »

Nice work HH.

Yes use the foam.

Those BA's will take the juice I'd give the subs as much as you can, and you'll prefer more. with config and power options I'd go the route of the Ti amps. I don't think you'll get enough outta the M setup. Overall I would personally go the Ta route, disassemble the BA XO's and paint the cover textured black to match the Tantrum finish, run the 500.2 to the midbass and track down a 350.2 for the mid/tweet or bridge the 400.4. Unless you are going to EQ each amp separate for the mid-highs I highly advise using the XO.


**Note when box building you don't need that many screws in fact it weakens the overall finished product. I know you've seen MDF and plywood split from being screwed to close to the edge, the same applies here but with more screws the whole thing can do that not just the edge. I will typically use 2-5 screws per edge, for example on your front baffle where you screwed into the dividers between chambers since the top and bottom were dado'd I would have only used a single screw in the center to hold it tight in the middle while the glue dried.
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maka78
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Post by maka78 »

Does the foam fill work for all sub boxes, or is it just for setting up the subs the way you have them (facing inside, forget what it's called)?
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HoseHead
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Post by HoseHead »

maka78 wrote:Does the foam fill work for all sub boxes, or is it just for setting up the subs the way you have them (facing inside, forget what it's called)?
The subs won't be facing into the cavity. I'm just showing the ass end of the BA woof in that photo. The entire box, in the trunk, will face the rear of the car to start off. I can turn it around or have the subs firing up also. I have an RTA en route that will provide correct tuning for each driver in the system.

HH
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HoseHead
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Post by HoseHead »

VW337 wrote:**Note when box building you don't need that many screws in fact it weakens the overall finished product. I know you've seen MDF and plywood split from being screwed to close to the edge, the same applies here but with more screws the whole thing can do that not just the edge. I will typically use 2-5 screws per edge, for example on your front baffle where you screwed into the dividers between chambers since the top and bottom were dadoed I would have only used a single screw in the center to hold it tight in the middle while the glue dried.
I hear you loud and clear. I avoided screws near the corner areas to avoid splitting the MDF. I also pre-drilled all holes, to reduce the chance of splitting. Next box will be all dadoes and much fewer screws. The dadoes also won;t allow the MDF to split. Thanks for the advice.
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HoseHead
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Post by HoseHead »

maka78 wrote:Does the foam fill work for all sub boxes, or is it just for setting up the subs the way you have them (facing inside, forget what it's called)?
In a sealed cavity, you need to absorb or break up the standing waves emitted from the rear of the cone. They can bounce off the cavity walls and relfect back against the cone, diminishing woofer performance. I just happened to find these foam pads originally used as packing for electronic cards at the office. We go through tons of them, so I decided to try them here.

I did some work at General Dynamics in Calgary for a few weeks last year. While I can't specifically detail what we were doing, we used a sound room. The room was about 16X16X9 and covered with this type of material. The foam cones were much larger and designed to absorb quite a variety of frequencies. You couldn't hear yourself speak while in the room. Really weird feeling. I'm applying the same here, but only need to absorb anything below 200 hz.

HH
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HoseHead
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Post by HoseHead »

She's sealed up.
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Just before the last LF dropped in. These should sound tighter than a redneck's puck at the gay pride parade.
Just before the last LF dropped in. These should sound tighter than a redneck's puck at the gay pride parade.
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The air resistance (using the gentle finger method) against the cone is night and day once the woofs were sealed. I tightened them in five sequences, using the cross method like a car tire.
The air resistance (using the gentle finger method) against the cone is night and day once the woofs were sealed. I tightened them in five sequences, using the cross method like a car tire.
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I used two foam pieces for the cavity rear face. The terminals had to poke through. All foam is adhered using LocTite adhesive spray. Use a nozzle tube for best control.
I used two foam pieces for the cavity rear face. The terminals had to poke through. All foam is adhered using LocTite adhesive spray. Use a nozzle tube for best control.
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A close up of the terminal from inside the cavity. I sealed it using the WeldBond glue. It ain;t coming out.
A close up of the terminal from inside the cavity. I sealed it using the WeldBond glue. It ain;t coming out.
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A bit more PG Porn. These are the same units as previously shown, just on display as art.
A bit more PG Porn. These are the same units as previously shown, just on display as art.
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