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Discussion Starter #1
The $469 price for the 21 is the DR motor – which is a 7.5” triple stacked motor, very beefy.

On the IB 21 – T/S are:

Fs: 21 Hz
Qms: 8.08
Qts: 0.67
Qes: 0.73
Mms: 419 g
BL: 15.35
Vas: 372.7 L
SPL: 90.5 1w/1m
 

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I'm sure others will weigh in, but the Fs of that driver looks relatively high.

The 21" Mal-X is tuned at 16.3 hz, for example.

Edit: There are plenty of LLT builds though - that use 18" drivers with a Fs similar to that driver.
 

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Discussion Starter #3
I wish I could afford some Maelstroms, RL-ps if they were still made, or if I could get my hands on some AA Avalanches... I simply can't afford them. The price tag with larger cone seem to help cheat a little, 27mm Xmax 21" cone... not a drop in for an 18" Mael, but I'd like to think it could be done.

Though I'd like to see a lower Fs myself, esp on a 21", my IB3s seem to do just fine with a 22Hz Fs. If I can sell my 4 IB3s for enough, I may try yo upgrade to these, cut the towers down, and use my spare room as a 990 cuft enclosure and use the door as a port, with some mods of course.

I wonder if the 21" MXs had a bad run as well, would be neat if the inductance rings could be removed and the drivers sold B-stock... I'm not crafty enough to pull the soft parts carefully and recone though.
 

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Hey "Andrew",

What driver is this? The price you state seems cool. Is this from Incriminator? Sorry, I'm not up on the car audio scene and I'm guessing that's where this one is coming from. Also, do you think they are a reliable source? Seems the biggest problem today is that you can't buy a driver when you want one...

And yeah, on looks seems good to me for an EB/LLT and even IB but I haven't modeled it.

-V
 

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Discussion Starter #5
Hi "V",

This is a modified Death Row from Incriminator, I believe a looser suspension and on a bigger cone. I think the regular DRs went up to 18" and had more/stiffer spiders. I have never purchased anything from Nick myself so I can not vouch for him. Not being able to buy a driver when you want one, thats sort of the reason for rallying for Mark at Mach 5 and Nick at IA... forum after forum, thread after thread, people are starved for the IB3...and it's the same ol tune... couple more weeks.

PS, V, just for kicks:

But on this most auspicious of nights, permit me then, in lieu of the more commonplace soubriquet, to suggest the character of this dramatis persona. Voila! In view humble vaudevillian veteran, cast vicariously as both victim and villain by the vicissitudes of fate. This visage, no mere veneer of vanity, is a vestige of the “vox populi” now vacant, vanished. However, this valorous visitation of a bygone vexation stands vivified, and has vowed to vanquish these venal and virulent vermin, van guarding vice and vouchsafing the violently vicious and voracious violation of volition.
The only verdict is vengeance; a vendetta, held as a votive not in vain, for the value and veracity of such shall one day vindicate the vigilant and the virtuous.
Verily this vichyssoise of verbiage veers most verbose, so let me simply add that it’s my very good honour to meet you and you may call me V.
 

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Elite Shackster
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TSPs look decent for IB use. The QTS is higher which is pretty important. Fs isnt as low as some drivers but IB's have the shallowest roll off of any sub type, and despite what some think, drivers can and do play well below FS. IB's generally relay on multiple drivers though, so I wouldnt go relying on a single driver if you install this as an IB. That brings us to another point, the reason for using multiple drivers is that IB's will run out of xmax pretty quick with only a single driver, which means limited max spl. You havent stated the xmax on this driver, which I will guess is not that high. To model it properly, your going to need to know the xmax, as well as the max power handling.

OH, and V for Vendetta is a quality film :T
 

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Discussion Starter #7
Hey Moonfly, the Xmax I was given is 27mm, 40mm Xmech. If I can get enough for my IB3s I plan to get 4 of these, 2 off each EP4000.
 

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Elite Shackster
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Do you know how to use WinISD?

If so, when modelling these drivers, take the combined Vas of 4 drivers, and times that figure by 10. This will give you the optimum volume requirement for the sub to work as a true IB. You simply model it as a sealed sub.

What is the stated max power handling of the drivers? Typically, I wouldnt expect it to be more than 500 watts, but if this driver is modded from an existing design, it may well be the motor can handle more, but an IB installation may simply not require it.
 

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Discussion Starter #9
This is generally a car audio sub, with him stating it's a very beefy motor with triple stack 7.5" slugs, I am sort of baffled why the BL appears low to me. I dont understand BL though.

I am looking to do a giant vented cabinet with a "pluggable" port... 990 cubic feet, manifold in the door way, cutting the door to close over top the manifold, door open it would be apx. 65"x28"x7" port, 10Hz-11Hz tuning.





earlier on quick WinISD mach ups, using 20" port (I have plenty of 20" sonotube left over from my van build" and 12" ports in the door.



 

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Not being able to buy a driver when you want one, thats sort of the reason for rallying for Mark at Mach 5 and Nick at IA... forum after forum, thread after thread, people are starved for the IB3...and it's the same ol tune... couple more weeks.
Yep, that's why the "big dogs" don't roll with drivers from these companies. Pretty much Eminence has their stuff together and you can almost always buy 8 or 12 or whatever Dayton's...

If I had to buy something now it would be the Aurasound 18" from Madisound.
 

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I am looking to do a giant vented cabinet with a "pluggable" port... 990 cubic feet, manifold in the door way, cutting the door to close over top the manifold, door open it would be apx. 65"x28"x7" port, 10Hz-11Hz tuning.
Ok I like the blue curve the best but you didn't tell us why you had the other tunings in there or what that one with the ~20 Hz tune was. I'm a little confused :wave:

EDIT: Modeled it and I like a 15- 20 Hz tune better. About 10 dB more at that tuning. I kinda think 10-11 Hz is too low but you've got more experience than I.
 

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Discussion Starter #13
Ha Ha yeah, I should probably memorize that one. But in my case, vann_d is not for vendetta...
Ive tried to memorize it, but its a bit tough, and Im glad youre not out on vendetta's

Yep, that's why the "big dogs" don't roll with drivers from these companies. Pretty much Eminence has their stuff together and you can almost always buy 8 or 12 or whatever Dayton's...

If I had to buy something now it would be the Aurasound 18" from Madisound.
I almost did 8 THTs with the Dayton 15's, but it was counter productive for what i was after. However I wish I woulod have done 3 of them in my van build, if not the 3 DTS-10's...either would have been nuts.

Oh that Aurasound 18 looks sweet, Ive glanced at it from time to time. Whats Xmax 25mm peak mean? Is that 25mm Xmax, or p-p for 12.5mm one way? 20Hz fs is sweet, neo is great, and UNDERHUNG! I wanna try an underhung with huge Xmax some day. $595 sort of brings things back to the others I mensioned though.
 

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Discussion Starter #14
Ok I like the blue curve the best but you didn't tell us why you had the other tunings in there or what that one with the ~20 Hz tune was. I'm a little confused :wave:

EDIT: Modeled it and I like a 15- 20 Hz tune better. About 10 dB more at that tuning. I kinda think 10-11 Hz is too low but you've got more experience than I.
Well my initial plan was just to use the entire doorway less the manifold for a port, but ThomasW on AVS and The Cult keeps yankin my leash back so to speak. Over on his forum, so far they are being accepting, he keeps trying to get me to build a manifold into the door so it's strictly true IB but I can get access to the room...but I have to keep the door shut to use it and I cant have vented as well. My whole point is I want to try IB and be able to model/test with REW against it, but most likely use it vented all the time. So then he was trying to talk me into making a manifold with the door and maybe "stick a port or 2 in it" So I was trying to show him that with 990 cubic feet, there's no sticking a port(s) in it... even with the entire door, building manifolds through the wall, tuning would be at 24Hz with 990 cubes 28"x90"x7" doorway.

Go to Home Depot buy a cheap solid core door, do something like this .......



 

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Whats Xmax 25mm peak mean? Is that 25mm Xmax, or p-p for 12.5mm one way? 20Hz fs is sweet, neo is great, and UNDERHUNG! I wanna try an underhung with huge Xmax some day. $595 sort of brings things back to the others I mensioned though.
From what I understand it's 25mm one way w/ 75mm peak-peak (37.5mm 0-p) Xlim and there is no real bottoming on this design, just soft parts stretching to limit.
 

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Elite Shackster
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Bl is a measure of the drivers motor force. IB drivers generally have a more loose suspension, and the IB installation essentially runs a driver in free air, as such high motor force just inst needed. Looking at your graphs, I dont like the look of the ported response at all, but you havent modelled the spl chart, which you need to do, and you need to look at the excursion chart too.
 

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Discussion Starter #18
From what I understand it's 25mm one way w/ 75mm peak-peak (37.5mm 0-p) Xlim and there is no real bottoming on this design, just soft parts stretching to limit.
I will reask the details on power handling and Xmax and Xlim/Xsus/Xmech

Bl is a measure of the drivers motor force. IB drivers generally have a more loose suspension, and the IB installation essentially runs a driver in free air, as such high motor force just inst needed. Looking at your graphs, I dont like the look of the ported response at all, but you havent modelled the spl chart, which you need to do, and you need to look at the excursion chart too.
I should have said I know what Bl is, but not in grave detail... B/Re or whatever? I know you can't just look at the Bl only, something about it being combined with the coil Re? So Bl being "only 15" on these, I know the IB3s were 9 and 11 and a SoloX 18 is 30 and 40... but is it a "big 15" vs what a "small 15" could be? Hope that makes sense. I'm guessing small Bl is desired for a smoother/flat responce in a larger enclosure.

Did Nick say what the power handling is on these subs?
I will ask.
 

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I should have said I know what Bl is, but not in grave detail... B/Re or whatever? I know you can't just look at the Bl only, something about it being combined with the coil Re? So Bl being "only 15" on these, I know the IB3s were 9 and 11 and a SoloX 18 is 30 and 40... but is it a "big 15" vs what a "small 15" could be? Hope that makes sense. I'm guessing small Bl is desired for a smoother/flat responce in a larger enclosure.
The Bl wont really affect the smoothness of the response curve, the cabinet is the largest factor that affects this. The higher the Bl the more motor force the motor has, so you only really need worry about Bl when you want a driver with a strong motor for application where that requirement is important. This would typically be in smaller cabinets and sealed cabinets. In your case, a lower Bl isnt going to be a major issue as there will be little damping effect from the cabinet upon the driver, and 15 Tm is fine for your use.
 

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Discussion Starter #20
Well it's high time I learn more about these TS params in better detail, thank you. My generalization was the big heavy motors, like car audio beasts like the Fi BTL, AA SMD, IA Warden and DP, SA Nightshade, AQ HDC3... all these huge motored powerful subs need to be loaded in small enclosures for a flat responce, in large enclosures they'd have a huge spike for a peak at tuning when vented or at Fs when sealed. On the contrary, tiny light motored subs would have a smooth flat FR in large enclosures but in small enclosures have a peak. When I put 2 IB3 18's in a 10 cubic foot box tuned to 35Hz, They were dead from 40Hz down, extrememly loud around 45Hz, and at 55Hz they were dead again.

I agree that the DRs will have plenty for the things I do, still a little fuzzy why " very beefy 7.5" tripple sluggs" are low.

Would cone area come into play? With the IB3s being smaller cones and having less Bl, the 21s being larger cones and a bit more Bl... does this keep things in line? If the 21's had the same 9 or 11 Bl like the 18's would that mean the 21 would have more trouble pushing a larger Mms?
 
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