4 x FI IB318 or 4x Dayton Ultimatix 18-22 for small IB Build

[mdp]

I have some small space behind the acoustic transparent screen. Its approx 14 ft long x 9 ft tall x 15" deep. I am thinking of doing a Infinite baffle + baffle wall build. The space behind screen will give me a box with approx 140 sq ft after taking L/C/R speaker volume out. I want to do 4 x 18" drivers, powered by a single iNuke 6000.

Now, I am torn between FI IB318 vs the upcoming Dayton Ultimatix 18-22. FI has a vas of 381 liters where as the Dayton has 214 liters. With FI, the IB box would be 2.8x Vas whereas with Dayton it will be over 4, which is recommended here. My question is - will the Dayton be a better option in my case? FI is like proven driver because it has been in so many builds, but not sure whether it will work in my scenario.

TIA

[ThomasW]

A little difficult to comment about a driver that doesn't exist.

I'd choose the Fi and it's 30+mm of Xmax for an IB.

I'd probably use the Dayton in a 'portable' sub application.

Be sure to fill the area you have for the rearwave with fiberglass batting

[mdp]

Thomas,

Thanks for the reply. With FI, I would get 2.8x vas volume. Will that be sufficient? Or am I better off dropping the IB idea and look for other solutions?

Yes, the Ultimatix is not yet released. But its vas (214 l) and Qts (.487) were the two thing I found better as per the IB FAQ. I plan to do this in summer, so can wait and see how that driver turns out.

[gworrel]

Modeling both drivers in Winisd in 4267 liters, the Fi IB318 gives about 5dB more output at 20Hz at max excursion (122.7dB). At 40Hz, the advantage is almost 6dB. That is equivalent to about twice the number of drivers. At 10 Hz, the advantage falls to about 2dB. The Fi drivers require about 2000 total watts (500 each) to get there. The Dayton drivers need about 1400 watts total to reach xmax at 10Hz in this size enclosure. The Fi drivers are clearly the better choice here, unless the Dayton drivers prove to drastically outperform their projected specs.

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[mdp]

Thanks for those graphs. So looks like the FI IB318 is still the best choice. I would probably use the insulation bats generously inside to reduce the back wave somewhat.

thanks again.

[mdp]

A follow up question. Would it help if I use 2 drivers instead of 4? That will definitely get in the range of 4x vas.

[ThomasW]

You're way to fixated on the Vas thing as a determining factor.

That said, given how small the room is a pair of 18"s will probably be more than enough.

[mdp]

Yes, I am quite fixated upon it. But its quite baffling to understand how to implement this.

Some info on the room. Room is 13 ft wide x 20 ft long. There is a 66" opening in the back of room which opens to living room and kitchen. It's the open floor plan. Because its a big area, I am leaning towards quad drivers. That and you get a nice $20 discount per driver from Fi Car Audio.

[ThomasW]

What are the dimensions of the HT?

What's the distance from the proposed location of the IB to the listening position?

[mdp]

Thomas,

HT is approx 13.8 ft wide, 20 ft long. Ceiling is vaulted, approx 8.5 ft at the side walls and 1.5 ft at the center.
If made into baffle wall, 18" from the front wall will be the screen. That will be the position for IB as well. Listening position is approx 12 ft from there.
thanks,

[mdp]

Want to give a update. I bought 4 x FI IB318. Will place an order for inuke 6000 and start the build soon.

[mdp]

Update - Finished this build. Here are some pictures.

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[ThomasW]

Looking good so far......

How does it sound?

[mdp]

Thanks Tom,

I unfortunately can't hear it yet. Still waiting for Behringer Inuke 6000DSP order to ship. It has been out of stock everywhere since last one month.