Isobaric - less then $20

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See now why we need you Dan!

Only played the big 3 fer box for 1 minute, shook the whole room.

The double woofer (behind) was a bit easier to listen to.
Interesting... What's the difference?
294880d1344281290-isobaric-less-then-20-3-p2s.jpg

:scratch:Borrowed the shrink ray from work again eh?
An externally hosted image should be here but it was not working when we last tested it.
 
Hey big brother!

The 3 box is really powerful, it would probably win a contest f they had a 3 - 8" woofer category.

I did not think it was what I was looking for, for HT (the bass hit too hard).

I've been wanting to try it in a car with a good amp, never got around to it. The box is 3x the recommend RFG volume tuned to 30hz (if I remember correctly); used the sliding front baffle w/camps ploy.

What is the tiny black box?
 
Thanks...... that was my 1st thought.

Here is the no math - non committal way to tune up a simple BR speaker.

Three parts:

1. 4 sided box, 1 side, top/bottom & back, all glued up.
2. Sliding front board with "L" slot port.
3. Other side (on top in photo).

Okay that's it, just move it around a bit until it's tuned where you need.

Pretty fast/easy.........works every time.
 

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Took a couple reads Doug but that makes alot of sense. Just vary the area of he vent till it hits where you want.

Are you playing a specific tone till you hit minimum motion to determine tuning?

Do you find that you sometimes have overlap between minimum motion and too narow a vent to pass enough air without turbulence?
 
Well you do need:

Volume and box tuning: WinISD or similar (or manufacture recommendation)

There is a resistor and generator off to the left.

Sweep the generator and read the volt meter (this is old school)

I see some say they use a white dot on the cone.

btw it the clamps are removed - there will be 3 separate parts, it is not all glued at this point.
 
The Sunfire is my "daily driver" as it's the sub for my computer workstation.
The 4-15" sub is visiting a friends house, they are afraid of it. I've also just sold my 3-18" Exodus Maelstrom-X drivers and so I no longer do indoor HT like I used to. I much prefer to drag out a bigger horn setup for outdoor projection HT at a friends place in the country.
 
Better pic.

The "L" board will lift right out. I did end up cutting at the black pencil line.

Remember to leave "last side" larger than the side that lays out on the table.

*****
Using the generator/load resistor/volt meter, the goal is:

1. Both peaks should be the same.
2. Valley should be equal to the speaker's free air resonance.

This is easy if the box size is correct (in the right ball park).



Took a couple reads Doug but that makes alot of sense. Just vary the area of he vent till it hits where you want.

Are you playing a specific tone till you hit minimum motion to determine tuning?

Do you find that you sometimes have overlap between minimum motion and too narow a vent to pass enough air without turbulence?
 

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I'm sorry if I'm asking questions that have been answered, but I have only managed to read up to page 18 so far, and my eyes hurt!
NEO Dan said both drivers need to see the same signal; I will be using a Parasound 5 channel power amp, 4 channels for the 4 drivers. Seem reasonable or not?
And would mounting the 2 'baric drivers close together, but at 45 degrees, be a problem?
 
There is no need to use a separate channel per driver when you can wire all 4 drivers in series parallel to get the same 4Ω load. Doing this will ensure the drivers receive "exactly the same" signal. One channel should be enough to power the set to the linear limit and beyond...
 
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