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Discussion Starter · #1 ·
To me, I like certain specs and choose my speakers acordingly, then I determine what box I would prefer for the location it needs to fit in. I like low Fs, high Xmax basically. I have a grasp on most of the Thiele/Small, but not a thourough knowledge on all of them. Example, I get Mms is the mass of the moving parts combined with the mass of the air it moves. A thick heavy cone, larger coil, weighted dustcap...and a larger Sd creates larger Mms, which lowers Fs, lowers transients? (I have ideas but don't know)... yadda.

So I have a feel of things, but at the end of the day, I want a large clean stroke and I like smooth responce and low extention. I am a Tumult/Brahma/Avalanche/Maelstrom-X/Tempest-X kinda guy. RL-p not so much, they look awesome, but the rubber/plastic doesn't fit the same mould to me though the motor topology, not being XBL^2, is similar and parameters are similar.

But I don't believe in EBP. I know it works, it's tried and true, but I know which drivers I like, but if I have almost no room, I know the above subs will sound great in a sealed enclosure. If I get enough room to go ported and low, then I will reinforce the low end. I am just now getting into IB.

So I'm not getting my Avalanches back, the Maelstrom-X's don't have much for coil options, so along comes this cheap yet awesome Fi IB18.

I have a daily driver that my woman drives with my son. She's not into systems yet, but curious. We need trunk space, and not a whole lot for output. (I'm a basshead, so by not a lot of output, I mean I was going to run just the pair of 15" Avalanches sealed)

I might throw 1 IB18 in there in a large sealed if i can't get enough airspace to tune sub 30's.

I would like to get another dedicated SUV someday and wall 2 IB18's @ 16Hz for fun and wow factor.

I would like to build an IB manifold as well.


So couldn't a guy get the 4 or more IB18's for the deal, and use them in different enclosures and all function just fine?
 

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I might throw 1 IB18 in there in a large sealed if i can't get enough airspace to tune sub 30's.
Model the IB18 in whatever size box the above would be and compare it against a box that is 10 times the Vas, which is what the IB18 was designed for. This comparison will show you the difference.
 

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Discussion Starter · #3 ·
I just ran out and measured the trunk as conservatively as possible. The one I am worried about most is trying to throw an IB18 in a trunk.

External 40" X 20" X16"

3/4" mdf, slot port all along the back and up 1 side to the front... 3" X 18.5" X 53"

Internal airspace about 3.7-3.8 cubes after sub displacement (terrible!) but 26Hz tune!

Will this work?

otherwise sealed would be a nice 5.8-5.9 ( NOOOO!!!! )
 

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Discussion Starter · #7 ·
I want to say so bad that it can probably handle much more than that, but especially not after seeing Scott's post about being happy to be dealing with HT more, and not liking car guys trying to throw 2 gigawatts at 250 watt subs lol.

I feared there wouldn't be an easy "fix" to my sub situation. I fear I need to find different subs for different applications...so i can still get 4 IB18's and I'll just have to run all 4 IB in home :bigsmile:

As for the car, I don't even know if i will do either... daily or dedicated :huh:

(edit: and in-car will see much less excursion than that even)
 

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Discussion Starter · #9 ·
hehehehe..... ok ok ok, youre right... I have learned that lesson enough.

So I'm thinking for the car, i already have a dual sealed box for a pair of 15's built...I should check into a pair of those Tempests, look for some used Tumults, or...

How about a Maelstom-X in that same box? I keep hearing the thing likes up to 3000 watts...

OK...fine...I'm gonna go look up manufacturer recommendations now :whistling:
 

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Discussion Starter · #10 ·
Alright Mike,

So I got to read a little on the LLT... and i'm glad I did. While fantasizing about these IB's, I kept finding myself wanting to "cheat" it to use the rear wave any way. I need to stick to large and low tuned.

But, I was thinking earlier, how about using an IB18 infinite baffle in car? I mean the in-car definition of sealing the trunk off and mounting the sub in between the two. I know the trunk won't give 10X Vas.... but would this work well? It would make me a little less annoying driving by from front to back cancellation, I think it would require considerably less power.... still a decent FR curve???
 

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Discussion Starter · #12 ·
I would have to take some measurments tomorrow, but it's an average trunk, and will totally not fit HT definitions... but i'd have to say for a general car IB, should be neat. I'll snap some pics too, and try to put in some things for size references.

, i will see if the GF will come out with me right now!

back ina bit.
 

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From what I can find, the trunk volume of a 2004 Toyota Camry is 13.8 cu.ft. With a Fi IB18 you would only be using 22mm of the 30 mm Xmax in that volume. If you really want to go loud and low, port a Malestrom and use the whole trunk for the cabinet and tune it to 16 hz.

Maelstrom.JPG

Add to that the crazy amount of cabin gain. Josh did a test in a Jeep WJ and got 36db gain at 9.5hz.

http://www.hometheatershack.com/for...led-ported/14209-monster-quest-room-gain.html

(5th graph from the top.)
 

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Discussion Starter · #15 · (Edited)
I think in real world, the subwoofer would still have decent excursion at its suggested power rating, especially since a trunk will be tough to make air tight... so factoring losses and leaks and such. And I hate to say it out loud, but I think another 100-200 watts would be OK... I'm thinking the power rating is assuming IB, not IRRC or whatever... I would guess in a 2 cu ft sealed enclosure, 800 watts wouldn't kill it, would it?

And I just saw there is now a 15" version!



We are talking about this IB18, right?

The new IB 18 features a 3" coil and a triple stacked motor specific for the IB application (smaller than the older Q series modified IB drivers and a little more purpose built overall).
Specs are:

Re 1.5 Ohms (single 2 Ohm coil)
Le .87mH
Fs 22.9 hz
Qms 3.25
Qes .79
Qts .63
Vas 381 l
Mms 258 g
Sd 1210 cm^2
Spl 89.4 1W/1m

Xmax is 30mm and suspension and motor limit right about at the same time.
At about 500-600 W it hits its linear limits at 20Hz. Power needs will vary accordingly.



Now... about this Maelstrom-X... :D I love this idea. No one has ever given me the go ahead to do 16Hz in car! I'm ecstatic, but the ol lady does want some trunk space, and I don't see how I could fit a box in there big enough any way to get 16Hz!

But I'm listening....
 

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Re 1.5 Ohms (single 2 Ohm coil)
Le .87mH
Fs 22.9 hz
Qms 3.25
Qes .79
Qts .63
Vas 381 l
Mms 258 g
Sd 1210 cm^2
Spl 89.4 1W/1m

Xmax is 30mm and suspension and motor limit right about at the same time.
At about 500-600 W it hits its linear limits at 20Hz. Power needs will vary accordingly.
Those specs are from a year ago. Fi just release a new series called the IB3.

https://ssl.perfora.net/www.ficarau...Speakers/0050_IB3/product_overview.shopscript

Still waiting to find out what the parameters are. As for the Maelstrom-X, I was just putting it out there. I'm out of my element with this. If you're really interested in the IB possibilities, head over to the SSA forum. There's way more knowledge over there regarding car audio IB installs.

http://www.soundsolutionsaudio.com/forum/index.php?
 

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Discussion Starter · #17 ·
I was trying to argue as much as possible to exhaust this unfortunate want I have to work with Ascendant/Fi. Stupid, and I apologize.

I am normally the 1st to get stuck on the very best, even if it means spending considerably more unless things go over the top.... I really wanted a 15" Tumult back in the day, but then the Avalanche price thing happened making it possible to get it now, not half a year saving. It drove me nuts all the people that got the Atlas instead simply because it was cheaper.

I really do want the Mael... it's got 3 more mm, it's got the 40mm headroom, and it's got the lower Fs.... I totally know I really want it for the extra 150 bucks. I know I do, but I keep trying to talk myself into getting a bunch of IB18's instead of 1 Mael-x at a time.

When I argue with ya, I know I'm coming to you for knowledge... I'm pushing you a little I guess to convince me a little more.

This Mael is obviousely more suited for a car, any car amp will have a lot more power and I'll need user-error headroom. I don't know that IB will work for it, because that arch in the rear seat/trunk opening is only 13" tall, and total height its just barely 20". If I did it, I'd have to slant the baffle, having to work around every groove, and it would come out past the wheel well... and we can't cover that! I don't see an 18" destined to be "" IB "" in that car, no matter the driver. Could do a pair of 10's or a 15", but I want to start using 18's now.

I do see finding some way to squeeze a single 18 in there though, 1 way or another, that we will be satisfied with.

Still hangin with me?
 

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unfortunate (want) I have to work with Ascendant/Fi.
That was 3 years ago. It's a whole new ball game now. Clean slate. :T

It drove me nuts all the people that got the Atlas instead simply because it was cheaper.
And I reget it. Almost everyday. :duh:


but I keep trying to talk myself into getting a bunch of IB18's instead of 1 Mael-x at a time.
Whether you convince your self or not on the IB18's, nothing is going to change the graph in post #18. Both subs will respond to your application differently. It depends on what you want and what you're willing to accept performance wise.

Still hangin with me?
Still here. :yes:
 

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Discussion Starter · #19 ·
OK... so I can't use the whole trunk for the enclosure... I'd love to, but we have a 6mo old and it's crazy enough she's letting me do anything at all. So believe me, if/when I do my dedicated, I've already made another thread on the SUV I plan on doing with dual 18's walled @ 16Hz....

Are you thinking no IB for the Maelstrom in this either?





Here's 2 threads on my dedicated...

http://www.hometheatershack.com/for...s-dual-18s-8hz-bottom-c-stuffing-effects.html

http://www.avsforum.com/avs-vb/showthread.php?t=1074047

Man, I hope I can do that as well! Too many fish to fry :) we can start with this daily driver that will keep me and mom happy, w/o poppin Hudson's ears!
 

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Discussion Starter · #20 ·
here's what we will probably throw in the daily driver for front stage, I'll just start from scratch with the dedicated if that ever comes about.

4 Adire Audio Extremis 6.4's, I have a Kicker KX850.4 for them and an Audio Control 6XS, I need to get a second one so I can bandpass the 4.5's and 6.5's with a 24dB slope for everything.

They will cover 50Hz-750Hz (same as Kit LCR crossover points)








2 Adire FR125S's...only available 8ohm. I have a Kicker KX350.4 that I will bridge for these.

They will cover 750Hz-3.5kHz




And 2 Vifa XT25TG30 1" Ring Radiator Tweets doing 3.5kHz on up




the inside of my first sloppy resined enclosure that had 1 Ava, 4th order, I designed on Shavano.com before I knew how to use BBP6 and WinISD. S factor of .7 and F3L of 20Hz.

 
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