derekwwww said:
Even two 12 inchers are better than a single 15 incher if they have comparable fs and Xmax if space doesn't matter.
They won't sound sloppy in big boxes, they'll sound better.
So, you could do a single 600 liters boxes with four woofers (huge, heavy, impressive, overkill), or two 300 liters boxes with two woofers in each, tuned to 15 Hz. You won't need a highpass crossover since the curve is more linear. Now with 250W RMS per woofer, you'll get a stupid high 118 dB at 17 Hz. In a room, corner loaded (design it as a corner table or something), it will be 128 dB at any frequency from 14.5 Hz to the crossover frequency.
It's a bit overkill, 2 woofers would be enough, you could do two 5 cubic feet internal boxes, or one single box of 10 cubic feet with one woofer frontfiring and another rearfiring to reduce distortion.
Still around 122 dB in room corner loaded from 14.5 Hz to the crossover frequency.
Group delay is really acceptable, 8 ms at 25 Hz.
I could help you get this smaller if you wish... hehe!
I checked for fun the Cerwin Vega driver, you could go a bit lower, but less SPL versus two 12 inchers. Also vent length are problematic.
I just ran some numbers for the IDQ-12 and the Titanic Mk3 15 through WinISD just so you know what to expect.
The good news is that you'll be able to use alot smaller of a box (1.821^3) for an IDQ-12 than either a sealed or ported Titanic. An advantage if you're going with multiple units.
You'll have to be creative to fit the 17.63" L, 4" ID pipe it needs,
into that box.
You'll also loose some low end extension (21.1hz vs 35.5hz) that the big 15 incher would have. On music you won't be missing much but you'll be giving up a little on movie sound effects.
More handy facts. The Titanic has more than double the X-max of the IDQ-12 so even if the IDQ-12 could play as low as the Titanic, i'd take two of 'em to get the same output.
Yes, 4-12's will be louder, but not lower. I don't think many folks putting 1KW into a Titanic are complaining about it not being loud enough, but then, it isn't what you'd call a "boom" sub.
Also, in a sealed box with a Q of .7, the IDQ-12 has an f3 point of around 55.5hz, not very deep at all.
The good news is that you'll be able to use alot smaller of a box (1.821^3) for an IDQ-12 than either a sealed or ported Titanic. An advantage if you're going with multiple units.
You'll have to be creative to fit the 17.63" L, 4" ID pipe it needs,
into that box.
You'll also loose some low end extension (21.1hz vs 35.5hz) that the big 15 incher would have. On music you won't be missing much but you'll be giving up a little on movie sound effects.
More handy facts. The Titanic has more than double the X-max of the IDQ-12 so even if the IDQ-12 could play as low as the Titanic, i'd take two of 'em to get the same output.
Yes, 4-12's will be louder, but not lower. I don't think many folks putting 1KW into a Titanic are complaining about it not being loud enough, but then, it isn't what you'd call a "boom" sub.
Also, in a sealed box with a Q of .7, the IDQ-12 has an f3 point of around 55.5hz, not very deep at all.
You're tuning the IDQ12 way too high.
You're right about the sealed box part, it's not a really good choice for a sealed box. Then again, in a critically damped box, Q = 0.5 it's looking quite good.
You're right about the sealed box part, it's not a really good choice for a sealed box. Then again, in a critically damped box, Q = 0.5 it's looking quite good.
Hey simon5, what box prog. are you using? I modeled the IDQ-12 in WinISD and it came up with a smaller box than yours.
Just for grins, I modeled dual 15" V-Max's in a sealed 300 liter box and it actually shows more output down to about 18Hz than dual IDQ-12's. Two 15's with double the X-max of 2-12's and greater output to below 20Hz. Can you say "structual damage" 😱 😀 . Imagine playing the "Meeting Darla" scene on THAT !
Just for grins, I modeled dual 15" V-Max's in a sealed 300 liter box and it actually shows more output down to about 18Hz than dual IDQ-12's. Two 15's with double the X-max of 2-12's and greater output to below 20Hz. Can you say "structual damage" 😱 😀 . Imagine playing the "Meeting Darla" scene on THAT !
I use WinISD like you. I don't use precalculated WinISD curves when I look at vented enclosures. I'm playing around with tuning frequency and box size until I achieve a shallow rolloff as deep as I can. This time it's hard to improve because vent lengths start to be impratical when I want to achieve the rolloff I'm looking after with this driver.
When I look at sealed enclosures, since I prefer vented, I'm almost always looking at critically damped Q = 0.5, to achieve almost the same rolloff.
I know it's a bit overkill to have a large box like that, but we are talking about serious response down to 14 Hz here.
Dual Vmax in a 300 liters box vs Dual IDQ12 D2 v2 in a 300 liters ported box? Yeah you got an advantage there, you can use 800W and I'm excursion limited with 375W so you win hands down 😉 You get a good bit more headroom, up to 4 dB higher. I get back the advantage under 20 Hz down to 12 Hz, then under 12 Hz you rule again.
Check if you're using the same IDQ12 D2 V2, more excursion than the old IDQ12.
But then, to beat everything, 300 liters with two Vmax tuned to 12 Hz. I would like to have the Le of the Vmax driver, do you know it?
When I look at sealed enclosures, since I prefer vented, I'm almost always looking at critically damped Q = 0.5, to achieve almost the same rolloff.
I know it's a bit overkill to have a large box like that, but we are talking about serious response down to 14 Hz here.
Dual Vmax in a 300 liters box vs Dual IDQ12 D2 v2 in a 300 liters ported box? Yeah you got an advantage there, you can use 800W and I'm excursion limited with 375W so you win hands down 😉 You get a good bit more headroom, up to 4 dB higher. I get back the advantage under 20 Hz down to 12 Hz, then under 12 Hz you rule again.
Check if you're using the same IDQ12 D2 V2, more excursion than the old IDQ12.
But then, to beat everything, 300 liters with two Vmax tuned to 12 Hz. I would like to have the Le of the Vmax driver, do you know it?
Is the reason you are tuning low down to 15 HZ and not say 20 HZ because of the time delay? Because I also use WinISD Pro and SPL output is good even tuned at 20hz (better then 15hz with same size box). And by corner loaded you mean have the woofers facing into a corner? Or facing out but in the corner? I don't think I need to tune down to 15 hz, but it seems that tuning at around 20 hz gives good SPL output, but high time delay in the low 20hz range. Is that such a bad thing? it seems like most ported subs have bad time delay in the low frequencies. If I went one box with all four, would I want all 4 facing out or two facing out two facing back? Same goes for towers with 2 in each.... both facing out, or 1 facing out 1 facing back?
derekwwww, with that much cone area, it'd be no prob getting all the output you want no matter which way they face.
simon5, can't help ya' there with a Le spec. C-V doesn't supply it.
simon5, can't help ya' there with a Le spec. C-V doesn't supply it.
Better sub for the money
Hello,
I have been usiing the NHT1259 that i purchased from Madisound. In 3 cubic foot sealed box, this thing is great!!!
I have used a lot of raw drivers includiing Audiom, focal, JBL, Pioneer (yes pioneer, the makers of 75% of the OEM drivers on the market) and for the money, this NHT 1259 is a fantastic driver.
Room f3 is down around 22hz!
Good SQ and outstanding base.
Hello,
I have been usiing the NHT1259 that i purchased from Madisound. In 3 cubic foot sealed box, this thing is great!!!
I have used a lot of raw drivers includiing Audiom, focal, JBL, Pioneer (yes pioneer, the makers of 75% of the OEM drivers on the market) and for the money, this NHT 1259 is a fantastic driver.
Room f3 is down around 22hz!
Good SQ and outstanding base.
Corner loaded means the subwoofer box is in a corner, the woofer can be facing front or anywhere else.
I'm tuning low to get group delay lower in the audible range and also because for movies it's awesome.
As I said, I could really make the boxes smaller by tuning to 20 Hz or so.
About tuning a same size box to 20 Hz... If you're not using some kind of EQ, it can sound a bit boomy. The low end will be a bit too loud. If you like club sound, you may like that anyway, it depends on how you like the sound.
Since it's a subwoofer, if you have a crossover lower than 80 Hz, you could do one woofer at the back and one woofer facing the front. By doing this, you remove a bit of distortion. Your enclosure is trying to rock forward and backward at the same time, so it's staying at the same place. It's not an absolute necessity, it will sound quite good if you do it the usual way.
If your crossover is higher, then you want to have all woofers frontfiring and it would be better to have two enclosures, to make it stereo.
About the group delay, most people will not notice much the group delay if it's under 25 ms at 20 Hz or so. Could be even higher and still be acceptable. Every ported box have a group delay, that's why there's some people that are hardcore about using only sealed subwoofers.
I'm tuning low to get group delay lower in the audible range and also because for movies it's awesome.
As I said, I could really make the boxes smaller by tuning to 20 Hz or so.
About tuning a same size box to 20 Hz... If you're not using some kind of EQ, it can sound a bit boomy. The low end will be a bit too loud. If you like club sound, you may like that anyway, it depends on how you like the sound.
Since it's a subwoofer, if you have a crossover lower than 80 Hz, you could do one woofer at the back and one woofer facing the front. By doing this, you remove a bit of distortion. Your enclosure is trying to rock forward and backward at the same time, so it's staying at the same place. It's not an absolute necessity, it will sound quite good if you do it the usual way.
If your crossover is higher, then you want to have all woofers frontfiring and it would be better to have two enclosures, to make it stereo.
About the group delay, most people will not notice much the group delay if it's under 25 ms at 20 Hz or so. Could be even higher and still be acceptable. Every ported box have a group delay, that's why there's some people that are hardcore about using only sealed subwoofers.
Derek, short answer on drivers: I think the Atlas 12" driver is better than the Titanic, based on a more linear motor design and a much lower inductance (0.86 mH for the Atlas vs 3.12mH for the Titanic), which means better transient response. It should have lower distortion as well, hence having more clean output so that there is less loss of SQ as you turn it up. It's quite a bit better for the same price.
I assume you mean "group delay?" Time delay would mean an equal delay to all frequencies, but GD varies with frequency. Note there are limits on how audible GD differences are. While there is some agreement that very high GD is not preferable, it's unclear at which point differences are audible. Is a GD of 12ms noticeably better than 16ms? The answer would depend on frequency, and if it is at 20 Hz, I doubt it would be audible.
I would not put too many drivers in one box - it will be big and heavy, difficult to get in a room, difficult to move, and you give up the advantages of having subs in different locations in the room, which yields a smoother in-room response if done correctly.
Note if you eq a sealed box to match the response of a vented sub, you will find the GD is very much the same - GD is related more to rolloff than the actual alignment (sealed or vented).
If you want sealed subs, 15" drivers are good bang for buck, not costing much more than their 12" versions. However, vented 12" subs will have more output and need bigger boxes.
I assume you mean "group delay?" Time delay would mean an equal delay to all frequencies, but GD varies with frequency. Note there are limits on how audible GD differences are. While there is some agreement that very high GD is not preferable, it's unclear at which point differences are audible. Is a GD of 12ms noticeably better than 16ms? The answer would depend on frequency, and if it is at 20 Hz, I doubt it would be audible.
I would not put too many drivers in one box - it will be big and heavy, difficult to get in a room, difficult to move, and you give up the advantages of having subs in different locations in the room, which yields a smoother in-room response if done correctly.
Note if you eq a sealed box to match the response of a vented sub, you will find the GD is very much the same - GD is related more to rolloff than the actual alignment (sealed or vented).
If you want sealed subs, 15" drivers are good bang for buck, not costing much more than their 12" versions. However, vented 12" subs will have more output and need bigger boxes.
Derek, short answer on drivers: I think the Atlas 12" driver is better than the Titanic, based on a more linear motor design and a much lower inductance (0.86 mH for the Atlas vs 3.12mH for the Titanic), which means better transient response. It should have lower distortion as well, hence having more clean output so that there is less loss of SQ as you turn it up. It's quite a bit better for the same price.
I assume you mean "group delay?" Time delay would mean an equal delay to all frequencies, but GD varies with frequency. Note there are limits on how audible GD differences are. While there is some agreement that very high GD is not preferable, it's unclear at which point differences are audible. Is a GD of 12ms noticeably better than 16ms? The answer would depend on frequency, and if it is at 20 Hz, I doubt it would be audible.
I would not put too many drivers in one box - it will be big and heavy, difficult to get in a room, difficult to move, and you give up the advantages of having subs in different locations in the room, which yields a smoother in-room response if done correctly.
Note if you eq a sealed box to match the response of a vented sub, you will find the GD is very much the same - GD is related more to rolloff than the actual alignment (sealed or vented).
If you want sealed subs, 15" drivers are good bang for buck, not costing much more than their 12" versions. However, vented 12" subs will have more output and need bigger boxes.
I assume you mean "group delay?" Time delay would mean an equal delay to all frequencies, but GD varies with frequency. Note there are limits on how audible GD differences are. While there is some agreement that very high GD is not preferable, it's unclear at which point differences are audible. Is a GD of 12ms noticeably better than 16ms? The answer would depend on frequency, and if it is at 20 Hz, I doubt it would be audible.
I would not put too many drivers in one box - it will be big and heavy, difficult to get in a room, difficult to move, and you give up the advantages of having subs in different locations in the room, which yields a smoother in-room response if done correctly.
Note if you eq a sealed box to match the response of a vented sub, you will find the GD is very much the same - GD is related more to rolloff than the actual alignment (sealed or vented).
If you want sealed subs, 15" drivers are good bang for buck, not costing much more than their 12" versions. However, vented 12" subs will have more output and need bigger boxes.
Derek, short answer on drivers: I think the Atlas 12" driver is better than the Titanic, based on a more linear motor design and a much lower inductance (0.86 mH for the Atlas vs 3.12mH for the Titanic), which means better transient response. It should have lower distortion as well, hence having more clean output so that there is less loss of SQ as you turn it up. It's quite a bit better for the same price.
I assume you mean "group delay?" Time delay would mean an equal delay to all frequencies, but GD varies with frequency. Note there are limits on how audible GD differences are. While there is some agreement that very high GD is not preferable, it's unclear at which point differences are audible. Is a GD of 12ms noticeably better than 16ms? The answer would depend on frequency, and if it is at 20 Hz, I doubt it would be audible.
I would not put too many drivers in one box - it will be big and heavy, difficult to get in a room, difficult to move, and you give up the advantages of having subs in different locations in the room, which yields a smoother in-room response if done correctly.
Note if you eq a sealed box to match the response of a vented sub, you will find the GD is very much the same - GD is related more to rolloff than the actual alignment (sealed or vented).
If you want sealed subs, 15" drivers are good bang for buck, not costing much more than their 12" versions. However, vented 12" subs will have more output and need bigger boxes.
I assume you mean "group delay?" Time delay would mean an equal delay to all frequencies, but GD varies with frequency. Note there are limits on how audible GD differences are. While there is some agreement that very high GD is not preferable, it's unclear at which point differences are audible. Is a GD of 12ms noticeably better than 16ms? The answer would depend on frequency, and if it is at 20 Hz, I doubt it would be audible.
I would not put too many drivers in one box - it will be big and heavy, difficult to get in a room, difficult to move, and you give up the advantages of having subs in different locations in the room, which yields a smoother in-room response if done correctly.
Note if you eq a sealed box to match the response of a vented sub, you will find the GD is very much the same - GD is related more to rolloff than the actual alignment (sealed or vented).
If you want sealed subs, 15" drivers are good bang for buck, not costing much more than their 12" versions. However, vented 12" subs will have more output and need bigger boxes.
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