# Ultimate IB sub



## kaigoss69 (Apr 2, 2008)

Would appreciate everyone's input. I am currently running an AE SBP-15 through the ski pass. The trunk is roughly 16 cu. ft. I have 500W available from an HD 900/5.

What is the absolutely best *single* IB sub I can put in this application? I am primarily looking for SQ not SPL, but of course it does need to be able to keep up with the rest of the system. Not interested in upping the power. 

I am VERY tempted to try the JBL cause I can get it for under $400 new.

The usual suspects are:


Dyn Esotar 1200
JBL W15GTI MkII
AE SBP-15
FI IB315
JL 13W7

Thoughts?


----------



## BuickGN (May 29, 2009)

You've got a great list already, pretty much every sub I would suggest except for the Fi. It would be so hard to pick just one, I think you would be happy with any of them. If I were forced to, I would go with the Esotar 1200 but not easily. For just perfect bass no matter what kind of music you listen to, it's warm yet detailed, digs deep effortlessly, it's very "quick" on rock, just all around perfect, a sub that I just can't find fault with. It is small for a 12", it has the cone area of an 11". Xmax is ok, xmech is good, it should have the same or more output than an average 12.

I'm going to get killed for saying this but the 13W7 and 13W6 are right there with the Dyn IMO. The main reason I would choose those second to the Dyn is I have one complaint and it's not a big deal and most people would never notice it. If you want to lowpass it high like over 80hz they do roll off up top. Most people cross thier subs lower than that anyway. To be honest I think both of the JLs sound a lot like the Dyn. I love my AE IB15s but the 12W6 I ran for a while seemed to "hit harder", it had more punch to it than the AE sub. Also, while the JL's efficiency rating is not that good, I found both of them required very little power to hit xmax. I would have to look it up, it's in the klippel section somewhere but the W6 required roughly 280w I think to hit xmech which was around 25mm.

The 13W7 has more displacement than all of the other subs except for the Fi. I always try to find xmech numbers beause I believe they're important when going IB because chances are at some point you're going to exceed xmax. The 13W7 has over 50mm of one way throw. I've pushed the W6 and W7 subs waaaay past xmax and the suspension is almost dead quiet on a 16hz tone with a scary amoun of excursion. I don't know the xmech rating of the Fi sub but it's possible the W7 could have very close to the same displacement at the limit.

I wouldn't consider the FiIB3 because it's a home IB subwoofer and I don't think the trunk of the car is large enough, especially for a pair. The one review I saw around here of a pair of IB3 15s was not favorable other than the SPL potential. 

So I would choose the Dyn if money and output are not major concerns although you might be happier with a pair of them. Jerry (niebur3) started with just one 1200 IB and later added a second one so he would have some good insight.


----------



## BuickGN (May 29, 2009)

I meant to ask what you don't like about the AE sub. It will probably give the most SPL off of 500w and it sounds great.


----------



## kaigoss69 (Apr 2, 2008)

BuickGN said:


> I meant to ask what you don't like about the AE sub. It will probably give the most SPL off of 500w and it sounds great.


Good question, and thanks for your detailed answer. I guess i am one of those people who are never satisfied, lol. I am wondering if another sub will sound different somehow, more to my liking. If I had to put the finger on it though I would say it is a bit too transparent and tame for me. Who knows, perhaps it is also my install that is at fault, or the MS-8. Just tempted to try something different and see if I like it better or not.


----------



## fast94tracer (Jun 23, 2013)

interesting since im about to run 2 FI IB318's in my baffle.
all anyone ever told me was that i should choose a different front stage to go with them.


----------



## sqshoestring (Jun 19, 2007)

Some of the home IB subs have a huge Vas. In too small a trunk this will crank up the Q and you lose the real lows say <30Hz depending on how far you get into Vas. This will be worse with multiple subs, have to model them and see what you have. On the other hand some car IB subs might have to low a qts for my liking, all depends on what you want. You can easily end up with lots of spl with big vas.

I ran quad 12s and they were tuned higher than I liked, similar to what a huge vas does in a small trunk. Anyway I had to put a PEQ on them and that fixed the issue. Without the EQ they would blow me out of the car at 40-50hz no problem, but I hated the sound. That was how they modeled too, they dropped at 40 in near any sealed or IB. They still had a lot of output simply because they had so much cone area. I think they had more than the pair of 15s I run now, but the 15s I use minimal EQ. Also the quad 12s weighed a ton, made the car handle differently.


----------



## fast94tracer (Jun 23, 2013)

well i know the spec on my trunk is 15.5cf but im sure its more since the subs see air space not cargo space. the vas on the 18's are 381 but i cant model in winisd since my computer refuses to run it for some unknown reason.


----------



## sqshoestring (Jun 19, 2007)

Just saying for SQ you don't want to lose those low lows but if it is the tune you want that is fine, or you have massive cabin gain or something. High qts are way more sensitive to box size, once you get down around Vas they can change a lot its something to be aware of if you like 20-30hz.

I lose 1db at 20hz from it. My pyles are 5.1cf vas (so 10.2 total) in my trunk also rated 15cf cargo so I model 16cf and figure that is conservative. That makes 1.5X Vas on those, but it does not always come out like that.


----------



## fast94tracer (Jun 23, 2013)

what template in winisd should i be looking at for frequency response?


----------



## fast94tracer (Jun 23, 2013)

from what im noticing its not going to matter much what sub i choose i have modeled all the ones i would consider and all of them fall short and will need to be eq'ed to bring it up below 30hz since all of them seem to loose 3db by 25-30hz even the dynaudio esotar 1200


----------



## BuickGN (May 29, 2009)

fast94tracer said:


> from what im noticing its not going to matter much what sub i choose i have modeled all the ones i would consider and all of them fall short and will need to be eq'ed to bring it up below 30hz since all of them seem to loose 3db by 25-30hz even the dynaudio esotar 1200


Are you taking cabin gain into account? I have no eq on my subs now that I did a little work blocking/absorbing the backwave. Before this I had to boost 20-32js and cut 50-80hz. If anything mine are just a hair heavy in the 30hz range with no eq.


----------



## fast94tracer (Jun 23, 2013)

how would i model cabin gain and i have sealed the trunk from the cabin already.... expanding foam is a wonderful thing


----------



## BuickGN (May 29, 2009)

kaigoss69 said:


> Good question, and thanks for your detailed answer. I guess i am one of those people who are never satisfied, lol. I am wondering if another sub will sound different somehow, more to my liking. If I had to put the finger on it though I would say it is a bit too transparent and tame for me. Who knows, perhaps it is also my install that is at fault, or the MS-8. Just tempted to try something different and see if I like it better or not.


I know what you mean. Mine got a little more "brutal" when I got rid of the MS8. They also got better in the upper range when I stuffed a couple large pillows in the trunk to try and absorb/block the back wave. These subs seem to be sensitive to the backwave as in it passes through the light paper cone easily. That's just my theory anyway. 

I love these AE subs but I'm going to be switching sometime this year to a pair of 13W7s partially out of boredom and partially because I think that they just "hit" harder for lack of a better word.


----------



## edouble101 (Dec 9, 2010)

Here is my IB315 review that I posted on another forum.

Ordering: The Fi Audio website is easy to navigate. From the time I ordered the subs until the arrived at my house was around two weeks.

Unboxing impression: The motors and surround are large. These are no heavy weight contenders but for IB use they are beefy. The surround lets you know that these are high xmax drivers.

Install: I am using two IB315's powered by a Sundown Audio SAZ1500D v.3 @ 1 ohm and they are mounted IB in my 2008 Hyundai Elantra. The motors are facing the back seat. I use different settings for SQ and daily listening. For SQ I am using a 40hz/12db high pass and [email protected] low pass with a -13db cut on my H/U. This unusual cross over setting is the only way I was able to tame a heavily boosted low end. Dual 15" subwoofers with a high qts and small trunk in my vehicle is what dictated this. My JL Audio 8" midbass drivers mounted in the kicks help blend the subs into the front stage. For daily listening I use a 20hz/18db high pass with a 80hz/36db low pass with a -3db cut on my H/U. This gives me a heavily boosted low end. I often bump the sub bass level down on my H/U even for daily listening.

​Listening conclusion: I never had an install that produced 20-30hz frequencies to this extent. The overall SPL level isnt the loudest but the music reproduction under 30hz is nuts. I am very impressed with the design of these woofers. There are no mechanical noises and they soak up every watt of the 1500D. As with the unusual DSP settings I find the power consumption of the IB315's to be unusual for this class of driver. Most IB subs are not this power hungry. The design goal for the IB3 series is evident to be superior sub bass reproduction at a relatively high SPL level. Having a high QTS they may perform even better in a larger trunk or as a true infinite baffle setup in home or theater that may require less EQ and xover adjustment. For a SQ install two of the IB315 is certainly overkill. There is enough output to easily overcome the front stage.

​Conclusion: In my small sedan I do not see it possible to achieve this level of reproduction from 20-30hz while maintaining full use of the cargo area and spare tire. 30-80hz is impressive as well but the overall SPL level could be higher with typical ported enclosure sub stage. IMO 20-30hz with this much authority is very impressive and hard to achieve. From a biased SQ perspective this area of the sub stage requires heavy tuning. A battle of both worlds 

Pics: (I am using custom carbon fiber dustcaps)


----------



## fast94tracer (Jun 23, 2013)

thank you for your input. i am in no way a bass head but i want to get very low and cleanly and that is my reason for the 18"s 
once again thank you


----------



## edouble101 (Dec 9, 2010)

fast94tracer said:


> thank you for your input. i am in no way a bass head but i want to get very low and cleanly and that is my reason for the 18"s
> once again thank you


You live an hour from me. We could meet up for a demo.


----------



## fast94tracer (Jun 23, 2013)

Sounds good

I don't drive fast I fly low!!!


----------



## Oscar (Jun 20, 2010)

fast94tracer said:


> well i know the spec on my trunk is 15.5cf but im sure its more since the subs see air space not cargo space. the vas on the 18's are 381 but i cant model in winisd since my computer refuses to run it for some unknown reason.


Just for reference 15.5 ft³ would be "IB" for a 6.5" subwoofer (or something with a Vas ≈ 0.5 ft³), not 18s. With a massive 381L of Vas, dual 18s would experience significant shift in Q in only 15.5 ft³.


----------



## sqshoestring (Jun 19, 2007)

I should add I lose 1db at 20hz in 16cf compared to 100cf. I can EQ that back no problem, however if you get more it is not so easy.


----------



## copperears (Sep 2, 2010)

How about TC Sounds LMS-5400. After many lesser subs over the years, I finally feel like I've arrived. The best sounding sub I have ever heard. It never sounds strained, even when loud. Other than the weight, I would consider it ideal.


----------



## SkizeR (Apr 19, 2011)

BuickGN said:


> You've got a great list already, pretty much every sub I would suggest except for the Fi.


whys that?


----------



## BuickGN (May 29, 2009)

SkizeR said:


> whys that?


They're a home IB sub with a huge Vas and .7 Qts that will give a high Qtc in a trunk, especially in pairs.


----------



## TMR (Feb 18, 2009)

Aura 1808's


----------



## Pitmaster (Feb 16, 2010)

Welcome back and damn!


----------



## subterFUSE (Sep 21, 2009)

Oscar said:


> Just for reference 15.5 ft³ would be "IB" for a 6.5" subwoofer (or something with a Vas ≈ 0.5 ft³), not 18s. With a massive 381L of Vas, dual 18s would experience significant shift in Q in only 15.5 ft³.



I have a trunk that is listed as cargo volume of 14.1 ft^3 and was considering doing a pair of FaitalPro 15XL1400 subs infinite baffle. They have Vas of 2.6 ft^3

Do you think those subs will work given my trunk space?


----------



## fcarpio (Apr 29, 2008)

These sounded awesome! The side panel where they are mounted is connected to the trunk, so it is a true IB setup.

http://www.diymobileaudio.com/forum...lery/49538-infiniti-g37s-stealth-install.html



















Unfortunately I no longer own the car. I still have a couple of subs left for sale if interested.


----------



## sqshoestring (Jun 19, 2007)

If you get down to Vas you KNOW the Q will rise and put a bump in the response. If you are say 1.5 times Vas like I am, I lose 1db at 20hz and gain 1db at 30, not a big deal at all. But not all subs react the same to vas there are other factors, and why just like a box you should model them. So yes if you put pair of 18s in a small trunk, you should be looking at lower Vas subs for that install....in general.


----------



## MJ DOOM (Feb 13, 2010)

Anybody try the Dayton Audio DCS450-4 18" Classic Subwoofers? Two model well in a 16 cubic feet.


----------



## TheScottishBear (Feb 3, 2011)

MJ DOOM said:


> Anybody try the Dayton Audio DCS450-4 18" Classic Subwoofers? Two model well in a 16 cubic feet.


I run 3 of them IB in my car where the back seat used to be. I fabricated a baffle out of mdf, 2by's and fiberglass. Its bolted to the rear deck. It's so heavy I can barely lift the damn thing. They needed a little eq'ing in between 35-50 hz but it is the best sounding sub setup I have had in my car to date. 
There are a couple pictures in this thread of the front and back of the baffle. I think next year I am going to try a couple 21" B&C drivers IB. 
http://www.diymobileaudio.com/forum...1693-any-ever-used-dayotn-subs-their-car.html


----------



## kapone (Sep 22, 2009)

I'm running the JBL W15GTI Mk2 IB in the BMW. I don't know if it's the "ultimate" IB sub or not, but I haven't heard anything better so far. 

I was floored when I finally got my system wired up, and fired it up for the first time. I think I actually _gasped _when the first bass note hit. Almost a physical sensation. That's how sublime that sub is when running IB.

It IS a pretty deep sub, so may not work for everybody, but the 740's trunk is a cave..


----------



## kaigoss69 (Apr 2, 2008)

kapone said:


> I'm running the JBL W15GTI Mk2 IB in the BMW. I don't know if it's the "ultimate" IB sub or not, but I haven't heard anything better so far.
> 
> I was floored when I finally got my system wired up, and fired it up for the first time. I think I actually _gasped _when the first bass note hit. Almost a physical sensation. That's how sublime that sub is when running IB.
> 
> It IS a pretty deep sub, so may not work for everybody, but the 740's trunk is a cave..


Jesus I just wet myself a little bit I think... I just did some modeling of that sub today compared to the SBP15, and the AE actually comes out on top even with 250w more on the JBL, but I was still wondering if it would sound better or at least different, more to my liking than the AE. Hmmmmmm...


----------



## kapone (Sep 22, 2009)

It's that Differential Drive motor... perfect for IB, and should help in not killing/over excursion the sub..  The 92db (or is it 93? conflicting data) sensitivity doesn't hurt either, and neither does the >20mm Xmax. 

But all technical data aside, the sub is just _musical_. Very authoritative. And when running IB, it gets loud with very little power. I'm giving it 400w from a bridged 2 channel, and the gain is at 3 notches above minimal. That gain can shake a 4500lb car...


----------



## sqshoestring (Jun 19, 2007)

kaigoss69 said:


> Jesus I just wet myself a little bit I think... I just did some modeling of that sub today compared to the SBP15, and the AE actually comes out on top even with 250w more on the JBL, but I was still wondering if it would sound better or at least different, more to my liking than the AE. Hmmmmmm...


Of course it will sound different, its a much different sub. You could lay a lot of power on the GTi and abuse it...and it will deliver, its a big HD sub and very capable. Because of that it will be less efficient, the sound is not going to be bad but it is not tuned to sound perfect running IB. Likely it would need some EQ. All depends on what you are looking for. It is also physically big and heavy in order to do what it does.


----------



## BuickGN (May 29, 2009)

The jbl 15 has always intrigued me. However, displacement is virtually identical to the AE. The jbl has 1mm more xmax and the AE has more cone area. The AE has 75% lower inductance and the moving mass is 40% lighter. The AE has a lower Fs as well. 

Isn't the JBLs efficiency rated at 2.83v? I'm sure the JBL has a far better suspension and I'm sure it's more versatile but for IB use it doesn't look better on paper and it's not going to get louder on the low stuff since displacement is so close. I would like to hear both back to back but that will probably never happen.


----------



## MJ DOOM (Feb 13, 2010)

TheScottishBear said:


> I run 3 of them IB in my car where the back seat used to be. I fabricated a baffle out of mdf, 2by's and fiberglass. Its bolted to the rear deck. It's so heavy I can barely lift the damn thing. They needed a little eq'ing in between 35-50 hz but it is the best sounding sub setup I have had in my car to date.
> There are a couple pictures in this thread of the front and back of the baffle. I think next year I am going to try a couple 21" B&C drivers IB.
> http://www.diymobileaudio.com/forum...1693-any-ever-used-dayotn-subs-their-car.html


You think two would do well in 16 cubic foot trunk? Would a EQ be necessary?


----------



## TheScottishBear (Feb 3, 2011)

MJ DOOM said:


> You think two would do well in 16 cubic foot trunk? Would a EQ be necessary?


Yeah they will work great. I would keep them at or around the rms. Also you will need a sub sonic filter. I have mine set at 25hz. Eq is up to you. They do have a peak around 45 hz. I don't consider my stereo as a true sq system but wanted to make it as musical as possible. So the peak had to go.


----------



## sqshoestring (Jun 19, 2007)

BuickGN said:


> The jbl 15 has always intrigued me. However, displacement is virtually identical to the AE. The jbl has 1mm more xmax and the AE has more cone area. The AE has 75% lower inductance and the moving mass is 40% lighter. The AE has a lower Fs as well.
> 
> Isn't the JBLs efficiency rated at 2.83v? I'm sure the JBL has a far better suspension and I'm sure it's more versatile but for IB use it doesn't look better on paper and it's not going to get louder on the low stuff since displacement is so close. I would like to hear both back to back but that will probably never happen.


The advantage is they have shorting rings, not sure about the AE. The GTi you can run right into xmax hard and not worry about, that is a lot of output IB. Far as SQ well, I doubt they would be bad and think I modeled them once they were off a little for IB....since they are primarily a box sub far as I know. Andy recommended using them once, said EQ it and lay the hammer on them. In my experience if you are playing 80Hz and less you need a pretty crappy sub to actually have it sound bad, though it may not be perfect a sub this good is likely to work fairly well, with EQ as needed. But the AE are made for this more or less, but not sure they are made for abuse the GTi can take. All depends on your needs. Don't mean to sound like an az but you people can't say "what will X sub sound like IB in my car?" It depends on your trunk volume, what you like a sub to sound like, what power you want to use, etc. Should model them just like for a box.


----------



## Oscar (Jun 20, 2010)

sqshoestring said:


> The advantage is they have shorting rings, not sure about the AE. The GTi you can run right into xmax hard and not worry about, that is a lot of output IB. Far as SQ well, I doubt they would be bad and think I modeled them once they were off a little for IB....since they are primarily a box sub far as I know. Andy recommended using them once, said EQ it and lay the hammer on them. In my experience if you are playing 80Hz and less you need a pretty crappy sub to actually have it sound bad, though it may not be perfect a sub this good is likely to work fairly well, with EQ as needed. But the AE are made for this more or less, but not sure they are made for abuse the GTi can take. All depends on your needs. Donu't mean to sound like an az but you people can't say "what will X sub sound like IB in my car?" It depends on your trunk volume, what you like a sub to sound like, what power you want to use, etc. Should model them just like for a box.


The WGTi's dont have shorting rings. Unless I misunderstood...


----------



## sqshoestring (Jun 19, 2007)

My bad maybe the wrong term, what I mean is you can't bottom them out or not very easily....and that is always the limiting factor of an IB sub far as output. Yes you will encounter distortion at the limit of any sub, but you will get its full output. You don't want to push lesser subs beyond xmax when in IB, they will fail, and is likely why many manufacturers will not recommend their sub for IB if it works well for that or not.


----------



## BuickGN (May 29, 2009)

sqshoestring said:


> The advantage is they have shorting rings, not sure about the AE. The GTi you can run right into xmax hard and not worry about, that is a lot of output IB. Far as SQ well, I doubt they would be bad and think I modeled them once they were off a little for IB....since they are primarily a box sub far as I know. Andy recommended using them once, said EQ it and lay the hammer on them. In my experience if you are playing 80Hz and less you need a pretty crappy sub to actually have it sound bad, though it may not be perfect a sub this good is likely to work fairly well, with EQ as needed. But the AE are made for this more or less, but not sure they are made for abuse the GTi can take. All depends on your needs. Don't mean to sound like an az but you people can't say "what will X sub sound like IB in my car?" It depends on your trunk volume, what you like a sub to sound like, what power you want to use, etc. Should model them just like for a box.


From John of Acoustic Elegance:
*The IB15's have the single shorting ring, the full copper sleeve covering the entire pole. This was what Nick had found to be the most ideal overall solution to lower inductance, distortion, etc. It both decreases overall inductance and linearizes inductance through the range of motion. In this case though with the 2 layer copper coil, inductance is very low to begin with. All motor designs are run through FEA to maximize the field symmetry throughout the range of motion. *

So yes it does have the shorting ring and incredibly low inductance. I've sent them 1,000w at 16hz full tilt on accident for a second or two before I could reach the volume knob and there was no hard bottoming or other bad sounds. The JBL uses the differential drive technology where the motor will brake the VC when it leaves the gap so it can't bottom out or something to that effect. 

With similar xmax and with the AE having more cone area, the JBL is not going to get louder, at least not in the lower frequencies where displacement is the limiting factor. It needs to be clarified how the sensitivity spec was rated. We know the AE is 90.6db at 1w/1m but we don't know if the JBL is at 1w/1m. 

Modeling has value but with the trunk being so incredibly leaky, I think shooting for the general ballpark is close enough. Get it close enough that it won't require too much EQ but actual response will probably be different than the model. 

The AE had one unique quality that I've never experienced before. They sound exactly the same as output is increased. I had never noticed how subs change slightly in sound as the volume knob is cranked up until I installed the AEs. I actually started researching to see if anyone else had noticed the same thing and I found a post by John I think stating exactly what I experienced and attributed it to the low inductance and very little inductance change over the range of the stroke. My subs and my 3.5" midrange have the same inductance lol. 

I'm not one who thinks the TS specs will tell you how the sub will sound, I've used subs and midbass with nearly identical specs that sounded very different. But very low inductance and a very light moving mass along with good efficiency and a good amount of stroke is a good starting point. The JBL could very well sound better but I doubt anyone will ever try both in the same car. 

The one thing I've always wanted to know is what is the xmech of the JBL. Does the Differential Drive feature start reigning things in right after it's 20mm xmax or does it have another 20mm to go?


----------



## Oscar (Jun 20, 2010)

kapone said:


> I'm running the JBL W15GTI Mk2 IB in the BMW. I don't know if it's the "ultimate" IB sub or not, but I haven't heard anything better so far.
> 
> I was floored when I finally got my system wired up, and fired it up for the first time. I think I actually _gasped _when the first bass note hit. Almost a physical sensation. That's how sublime that sub is when running IB.
> 
> It IS a pretty deep sub, so may not work for everybody, but the 740's trunk is a cave..


This I can attest to. Even having had my W10GTi for nearly 9 years, I still marvel at how unbelieveably clean it sounds on any material.


----------



## kaigoss69 (Apr 2, 2008)

BuickGN said:


> The JBL could very well sound better but I doubt anyone will ever try both in the same car.


I am tempted to do just that!


----------



## Oscar (Jun 20, 2010)

BuickGN said:


> The AE had one unique quality that I've never experienced before. They sound exactly the same as output is increased.
> 
> The one thing I've always wanted to know is what is the xmech of the JBL. Does the Differential Drive feature start reigning things in right after it's 20mm xmax or does it have another 20mm to go?


I'd like to think the WGTIs also exhibit this great attribute. 

The suspension on the WGTi's would allow a bit more Xmech _if it were possible_. Once the coils leave their respective gap hand head towards the other one with reversed flux field, there's only a couple of mm before they hit that dead stop. Pretty sure it was done on purpose so as to "never" have to worry about torn spiders. 

Also "Differential Drive" does not just mean that there is magnetic braking---it refers to the motor topology where the same flux field is used twice with longitudinally separated voice coils which are biased inward toward each other (inner-hung). 

So basically, the Xmech would be just as one coil approaches the other gap--which is different in the W10GTi than the 12s and 15s (which I believe have identical motors/coils). I had posted a picture of the entire moving assembly of my W12GTi that I had to fix, along with measurements on the former. From it you could probably figure out a decently accurate value Xabs (Xabsolute--a new term that I have coined since technically the excursion is not "suspension" limited in the DDD motor  )

Edit...here ya go
























































Look at the symmetry of that flux (in _either_ gap)!


----------



## sqshoestring (Jun 19, 2007)

BuickGN said:


> From John of Acoustic Elegance:
> *The IB15's have the single shorting ring, the full copper sleeve covering the entire pole. This was what Nick had found to be the most ideal overall solution to lower inductance, distortion, etc. It both decreases overall inductance and linearizes inductance through the range of motion. In this case though with the 2 layer copper coil, inductance is very low to begin with. All motor designs are run through FEA to maximize the field symmetry throughout the range of motion. *
> 
> So yes it does have the shorting ring and incredibly low inductance. I've sent them 1,000w at 16hz full tilt on accident for a second or two before I could reach the volume knob and there was no hard bottoming or other bad sounds. The JBL uses the differential drive technology where the motor will brake the VC when it leaves the gap so it can't bottom out or something to that effect.
> ...


That is what I was thinking, braking coils or rings, way back in the day RF used to call them one of those. I had a 15 and lifted myself off the floor with my hands on the cone on a counter and it did not bottom, must have been around '90 or so and I weighed at least 170 then. Was very impressive at the time and deafening power on a LP5002 in a truck cab lol.

I agree its the specs changing with more xmax, or you are reaching xmax at low frequency so the higher frequency get louder. I get that easily with cheaper subs they get tight sounding at high outputs. But is OK if you have enough cone so that output is above your normal range of use....as it is with the pair of pyle 15s I run. I have to put about all my 500rms into them before I notice that happening and then it is over running the highs anyway, plus I don't use a SS filter.

The AE have to be one of the top SQ subs out there and a pair can certainly shake a car, I really like them. I was going to get a pair then he ran out of the old cheaper ones and I ran out of money at the time lol, had to find a cheaper alternative. I've read a lot about the JBL GTi they are a machine, I would have one if I had a use for that type of sub but I don't right now. The Fi look really impressive on paper but nobody seems to have run them IB and I don't know much about them.


----------



## kapone (Sep 22, 2009)

Oscar said:


> This I can attest to. Even having had my W10GTi for nearly 9 years, I still marvel at how unbelieveably clean it sounds on any material.


I run quad 15s (not GTIs) in my home theater and the "impact" of the W15GTi in the 740 is _almost_ the same. Of course that's one 15" sub pressurizing a much smaller space than a 1200 sqft theater, but you get the point.

In addition, my sub is mounted on a baffle, firing straight into the ski pass, with no obstructions to the airflow (just a grill incorporated into the rear armrest, and the armrest is almost always in the down position). So there isn't even a seat that the sound has to pass through.


----------



## thehatedguy (May 4, 2007)

I have a Dayton Reference HF in my car...it's nice, especially for the money.

However if it wasn't for the money, the WGTi and the AE subs were at the top of my list. I've loved every WGTi setup that I've heard and I think it actually has the suspension to do the rated excursion.


----------



## kaigoss69 (Apr 2, 2008)

Just for the hell of it, I modeled the IDMax and GTi against my current sub, the AE SBP15. Here's the max SPL graph, putting max Pe on each sub. AE looks good with just 500W, but IDMax with 1200W is considerably louder down low. Food for thought. Of course, there's much more to it than just theoretical SPL curves. I want a sub that can blend perfectly, stays musical no matter what volume, and can bring the house down if needed. I think the IDMax is in the lead...


----------



## dgage (Oct 1, 2013)

I know an IDMAX can handle 1200 watts in a box but infinite baffle? I have major doubts.


----------



## BuickGN (May 29, 2009)

Oscar said:


> I'd like to think the WGTIs also exhibit this great attribute.
> 
> The suspension on the WGTi's would allow a bit more Xmech _if it were possible_. Once the coils leave their respective gap hand head towards the other one with reversed flux field, there's only a couple of mm before they hit that dead stop. Pretty sure it was done on purpose so as to "never" have to worry about torn spiders.
> 
> ...


I don't know how I missed this the first time, thanks. So xmech could be significantly higher than xmax, right? I wouldn't mind trying a pair. Especially since sensitivity is good. Ever since I doubled the power to the midbass I get light dimming (not the headlights, just the interior dome light) so I'm not wanting to have to run any more power than I currently run.


----------



## BuickGN (May 29, 2009)

kaigoss69 said:


> Just for the hell of it, I modeled the IDMax and GTi against my current sub, the AE SBP15. Here's the max SPL graph, putting max Pe on each sub. AE looks good with just 500W, but IDMax with 1200W is considerably louder down low. Food for thought. Of course, there's much more to it than just theoretical SPL curves. I want a sub that can blend perfectly, stays musical no matter what volume, and can bring the house down if needed. I think the IDMax is in the lead...


Is there anything stopping you from running a second AE sub? It would still be cheaper. A pair of IDMax 15s would be nice though.


----------



## Oscar (Jun 20, 2010)

BuickGN said:


> I don't know how I missed this the first time, thanks. So xmech could be significantly higher than xmax, right? I wouldn't mind trying a pair. Especially since sensitivity is good. Ever since I doubled the power to the midbass I get light dimming (not the headlights, just the interior dome light) so I'm not wanting to have to run any more power than I currently run.


If I had to guesstimate (since I don't wish to subject my W12GTi to undue torture, lol), I'd say that one coil can get to within about 0.25" to the other gap before the repulsive forces overcome the ever decreasing force on the driving coil (on one-half of a AC waveform of course). Translating into metric, I'd venture to say the Xabs ≈ 29mm. Of course this is just pure speculation from what I know of the motors on the W12/15 GTi. I'm pretty sure the spider is large enough to accomodate such a guesstimate.


----------



## BuickGN (May 29, 2009)

I bet you're right. I looked at tons of retarded "flex" videos on YouTube and found at least one of the 12" versions with significantly more excursion than xmax. That's of course eyeballing a video but it was impressive.


----------



## Oscar (Jun 20, 2010)

yea I just saw this

JBL w12 GTI MKII @23Hz LBS Clio lele - YouTube

he now has mdf dust all over his cloth interior LOL


http://www.youtube.com/watch?v=GUnGiIdCHlk

this W15GTi, from eyeballing it, is doing a bit more than 22mm of excursion that it is rated for.

A couple of screenshots from that last video




















that looks closer to 1" to me.


----------

