Dual GJALLARHORNs! - Page 19 - AVS Forum
Forum Jump: 
 3Likes
Reply
 
Thread Tools
post #541 of 773 Old 10-13-2013, 01:00 PM
d_c
Advanced Member
 
d_c's Avatar
 
Join Date: Feb 2010
Location: KCMO
Posts: 615
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Liked: 62
What do you use for the amp settings on the back and front with the G-horn?

How did you have it set for sealed?

Thanks!
d_c is offline  
Sponsored Links
Advertisement
 
post #542 of 773 Old 10-13-2013, 01:59 PM - Thread Starter
AVS Special Member
 
lukeamdman's Avatar
 
Join Date: May 2011
Location: Burnsville, MN
Posts: 1,328
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
Liked: 113
Quote:
Originally Posted by d_c View Post

What do you use for the amp settings on the back and front with the G-horn?

How did you have it set for sealed?

Thanks!

When sealed, I had two 5400s per cabinet for an 8ohm load, so I ran the fp14k bridged. For that, I had the voltage gain on the back at max (default), and the gain on the front at half.

For the Ghorns, I have the amp in stereo, the voltage gain on the back at 41db, and the gains on the front at about 3/4.
lukeamdman is online now  
post #543 of 773 Old 10-13-2013, 04:07 PM
d_c
Advanced Member
 
d_c's Avatar
 
Join Date: Feb 2010
Location: KCMO
Posts: 615
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Liked: 62
What about the limiter settings?

Have fun with the ht room remodel, btw.
d_c is offline  
post #544 of 773 Old 10-13-2013, 04:18 PM - Thread Starter
AVS Special Member
 
lukeamdman's Avatar
 
Join Date: May 2011
Location: Burnsville, MN
Posts: 1,328
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
Liked: 113
Quote:
Originally Posted by d_c View Post

What about the limiter settings?

Have fun with the ht room remodel, btw.

I never changed the VPC settings, I just keep them at max.

Thanks!
lukeamdman is online now  
post #545 of 773 Old 10-17-2013, 11:11 AM - Thread Starter
AVS Special Member
 
lukeamdman's Avatar
 
Join Date: May 2011
Location: Burnsville, MN
Posts: 1,328
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
Liked: 113
I got some grief from Bosso and MK earlier on in this thread since I'd be losing 10hz and under going to the horns from the quad sealed setup. In my old room, quad 5400s did absolutely nothing from 13hz on down because of the acoustics in that room.

However, the new theater room looks VERY promising for 10hz and lower, since without a filter even the Ghorns are extending to 10hz, which shouldn't happen really.

Also, my new theater room has a ~12x25' utility/workout room directly behind it...I'm thinking 8x18" IB to cover 5hz-15hz?
lukeamdman is online now  
post #546 of 773 Old 10-17-2013, 12:42 PM
FOH
AVS Special Member
 
FOH's Avatar
 
Join Date: Apr 2010
Location: Midwest
Posts: 4,747
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 208
Achieving useable 5hz-15hz levels is a tall order.
Achieving useable 5hz-15hz levels w/an IB, while keeping up with the horns, is a monumental task.

------------------------------------
Flat, Deep, Clean, Linear, and Loud
------------------------------------
Active 16.8kw, 7.3 system
(3)Seaton Cat12C up front, (4)QSC K8 sides/rears
(2)Seaton SubM-HP, (4)18" IB
FOH is online now  
post #547 of 773 Old 10-17-2013, 01:45 PM - Thread Starter
AVS Special Member
 
lukeamdman's Avatar
 
Join Date: May 2011
Location: Burnsville, MN
Posts: 1,328
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
Liked: 113
Quote:
Originally Posted by FOH View Post

Achieving useable 5hz-15hz levels is a tall order.
Achieving useable 5hz-15hz levels w/an IB, while keeping up with the horns, is a monumental task.

Oh? Bummer, I was under the impression that IB was really efficient for sub 15hz material.
lukeamdman is online now  
post #548 of 773 Old 10-17-2013, 02:10 PM
AVS Addicted Member
 
MKtheater's Avatar
 
Join Date: Jul 2006
Location: New Hartford, NY
Posts: 14,347
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 153 Post(s)
Liked: 421
The GH gets 10hz output outside so it should indoors. An IB would get you the 5-15hz while matching the dynamic capability of the GH's up top, as well as the Othorns! The problem is dual GH's have a 20 dBs advantage at 20hz(biggest differential) over say the FI car Q driver sealed. 8 of those and you get 18 dBs of gain so very close.
MKtheater is offline  
post #549 of 773 Old 10-17-2013, 02:13 PM
AVS Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 16,137
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 205 Post(s)
Liked: 921
"Oh? Bummer, I was under the impression that IB was really efficient for sub 15hz material."

they are very efficient in the sense that they have no air spring resistance of a box, so it is VERY easy to drive them to their xmax limits (and beyond).

however, they are limited just like sealed subs in the amount of output to how much air they can move. a driver in an infinite baffle will be no more loud at the extreme than one in a sealed enclosure.

Listen. It's All Good.
LTD02 is offline  
post #550 of 773 Old 10-17-2013, 02:16 PM
FOH
AVS Special Member
 
FOH's Avatar
 
Join Date: Apr 2010
Location: Midwest
Posts: 4,747
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 208
Quote:
Originally Posted by lukeamdman View Post

Oh? Bummer, I was under the impression that IB was really efficient for sub 15hz material.

Well it is, it's not up against that high pass filter the box presents.

Upon second thought ....
Maybe I'm wrong or even just a bit skeptical about level potential. As we know, it all depends on all the variables; the drivers/amp, the proximity to the LP, dimensions of the space, composition and impedance of the boundaries. Living with both an IB and multiple small sealed, they're just so different. I'd suggest, ... as a loosely defined rule of thumb, it takes twice the swept area in an IB as one would otherwise need in a small sealed. But, limiting the IB to merely the region below the room's first mode, would likely change that 2:1 rule of thumb relationship in a positive direction, but how much I'm unsure.

Interesting

------------------------------------
Flat, Deep, Clean, Linear, and Loud
------------------------------------
Active 16.8kw, 7.3 system
(3)Seaton Cat12C up front, (4)QSC K8 sides/rears
(2)Seaton SubM-HP, (4)18" IB
FOH is online now  
post #551 of 773 Old 10-17-2013, 02:28 PM
AVS Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 16,137
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 205 Post(s)
Liked: 921
"it takes twice the swept area in an IB as one would otherwise need in a small sealed."

i'm wondering what you are thinking there as it would seem to go against the physics by which the two systems operate.

Listen. It's All Good.
LTD02 is offline  
post #552 of 773 Old 10-17-2013, 02:43 PM - Thread Starter
AVS Special Member
 
lukeamdman's Avatar
 
Join Date: May 2011
Location: Burnsville, MN
Posts: 1,328
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
Liked: 113
I was just looking at the FI IB3 specs, and it's a 30mm XMAX driver for only $250.

Since the idea is that these would be on the back wall, it'd be considered "near field" and only 3-4ft away from the LP. I was just thinking eight 18s nearfield with that high of XMAX would be pretty dang good. No?
lukeamdman is online now  
post #553 of 773 Old 10-17-2013, 02:56 PM
AVS Addicted Member
 
MKtheater's Avatar
 
Join Date: Jul 2006
Location: New Hartford, NY
Posts: 14,347
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 153 Post(s)
Liked: 421
That is what I am building and 57.6 liters of displacement would be good for anyone to 5hz. Now if your rom is over 6000 cubes maybe more and the price is around $2200 shipped for 8, I live in central NY and they come from Nevada.
MKtheater is offline  
post #554 of 773 Old 10-17-2013, 02:58 PM
Advanced Member
 
nfraso's Avatar
 
Join Date: May 2013
Posts: 578
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 164
If you built an IB system capable of hitting 5-15Hz at the same levels the GJs hit in it's "sweet spot", you'd already have all the 15-80Hz output you would need from the IB alone, no?

So what would be the point?

It's always fun in theory to think about optimally mixing all of these systems, but in the end the GJ was built to absolutely murder 16-80Hz in a decently sized cabinet with a single LMS-Ultra.

If you wanted 5Hz, the GJ doesn't even enter the equation, IMO. Whatever you build to hit 5Hz is going to carry the rest just as well.
nfraso is offline  
post #555 of 773 Old 10-17-2013, 03:22 PM - Thread Starter
AVS Special Member
 
lukeamdman's Avatar
 
Join Date: May 2011
Location: Burnsville, MN
Posts: 1,328
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
Liked: 113
Quote:
Originally Posted by MKtheater View Post

That is what I am building and 57.6 liters of displacement would be good for anyone to 5hz. Now if your rom is over 6000 cubes maybe more and the price is around $2200 shipped for 8, I live in central NY and they come from Nevada.

My room isn't even 2,500cu.ft...
Quote:
Originally Posted by nfraso View Post

If you built an IB system capable of hitting 5-15Hz at the same levels the GJs hit in it's "sweet spot", you'd already have all the 15-80Hz output you would need from the IB alone, no?

So what would be the point?

It's always fun in theory to think about optimally mixing all of these systems, but in the end the GJ was built to absolutely murder 16-80Hz in a decently sized cabinet with a single LMS-Ultra.

If you wanted 5Hz, the GJ doesn't even enter the equation, IMO. Whatever you build to hit 5Hz is going to carry the rest just as well.

From 13-100hz, I'm completely 100% satisfied. Whatever I build for 5-15hz is going to be BEHIND the LP, and near field. 50hz and up behind you mixing with the mains in front of you sounds like pure crap since you can localize the sound at those frequencies.

Another plus of the IB is I don't have to build more boxes!
lukeamdman is online now  
post #556 of 773 Old 10-17-2013, 04:02 PM
Bass Enabler
 
Scott Simonian's Avatar
 
Join Date: Oct 2001
Location: Clovis, CA
Posts: 13,447
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 291 Post(s)
Liked: 719
Sounds like you should build this 8 18" IB system. Yup. You want to already. You don't need us to convince you. wink.gif Do it!

My Dual 18" LLT subs 120dB down to 10hz

 

Plan9Reloaded Co-host

Listen to the Plan9Reloaded Gaming and Technology Podcast (may contain NSFW language)

https://soundcloud.com/plan9reloaded/sets/podcast - direct pod link

http://plan9reloaded.com/site/ - main website

Scott Simonian is offline  
post #557 of 773 Old 10-17-2013, 04:20 PM
AVS Addicted Member
 
MKtheater's Avatar
 
Join Date: Jul 2006
Location: New Hartford, NY
Posts: 14,347
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 153 Post(s)
Liked: 421
Quote:
Originally Posted by nfraso View Post

If you built an IB system capable of hitting 5-15Hz at the same levels the GJs hit in it's "sweet spot", you'd already have all the 15-80Hz output you would need from the IB alone, no?

So what would be the point?

It's always fun in theory to think about optimally mixing all of these systems, but in the end the GJ was built to absolutely murder 16-80Hz in a decently sized cabinet with a single LMS-Ultra.

If you wanted 5Hz, the GJ doesn't even enter the equation, IMO. Whatever you build to hit 5Hz is going to carry the rest just as well.

This correct, the IB would cover all bass frequencies.
MKtheater is offline  
post #558 of 773 Old 10-17-2013, 04:38 PM
AVS Special Member
 
chrapladm's Avatar
 
Join Date: Mar 2010
Posts: 2,610
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 95 Post(s)
Liked: 67
Where is AndreasMergner and his build? (DIY rotary)

That would cover the rest. It is what I would want to go from 2hz-20hz. Then horned the rest of the way. BUT this is only a dream for me right now.
chrapladm is offline  
post #559 of 773 Old 10-17-2013, 04:46 PM
Bass Enabler
 
Scott Simonian's Avatar
 
Join Date: Oct 2001
Location: Clovis, CA
Posts: 13,447
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 291 Post(s)
Liked: 719
I'd pay some VERY close attention to your signal chain if reproducing <10hz content is important. I'd do this before even thinking (well maybe not biggrin.gif) of putting in an IB system. Especially if it's point is to reproduce only 15hz and under.
nfraso likes this.

My Dual 18" LLT subs 120dB down to 10hz

 

Plan9Reloaded Co-host

Listen to the Plan9Reloaded Gaming and Technology Podcast (may contain NSFW language)

https://soundcloud.com/plan9reloaded/sets/podcast - direct pod link

http://plan9reloaded.com/site/ - main website

Scott Simonian is offline  
post #560 of 773 Old 10-17-2013, 07:50 PM
Advanced Member
 
nfraso's Avatar
 
Join Date: May 2013
Posts: 578
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 164
Quote:
Originally Posted by lukeamdman View Post

My room isn't even 2,500cu.ft...
From 13-100hz, I'm completely 100% satisfied. Whatever I build for 5-15hz is going to be BEHIND the LP, and near field. 50hz and up behind you mixing with the mains in front of you sounds like pure crap since you can localize the sound at those frequencies.

Another plus of the IB is I don't have to build more boxes!

I think you're still missing the fact that IB/sealed built with 5Hz output to match your current levels gives you a system capable of reproducing the entire bandwidth at those levels. So it would be redundant, and you may as well ditch the GH's at that point. Sure you can filter >50Hz for the heck of it and let the GHs take it, but you're just throwing extraneous drivers, power and $$ at something that could be achieved with less. Even more so considering the effort it took to build those bad boys.

Also, nearfield ULF doesn't really work unless you're doing something truly insane.

Think about the response of a sealed system at your seat versus a close mic. Huge difference at 5Hz. By running them nearfield, you're essentially taking the room out of it.

If it were that easy, we'd all be running just a pair of high excursion 15's on the end tables on either side of our couch a few feet from our ears to give us 3Hz at reference. biggrin.gif
nfraso is offline  
post #561 of 773 Old 10-17-2013, 09:22 PM - Thread Starter
AVS Special Member
 
lukeamdman's Avatar
 
Join Date: May 2011
Location: Burnsville, MN
Posts: 1,328
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
Liked: 113
Quote:
Originally Posted by nfraso View Post

I think you're still missing the fact that IB/sealed built with 5Hz output to match your current levels gives you a system capable of reproducing the entire bandwidth at those levels. So it would be redundant, and you may as well ditch the GH's at that point. Sure you can filter >50Hz for the heck of it and let the GHs take it, but you're just throwing extraneous drivers, power and $$ at something that could be achieved with less. Even more so considering the effort it took to build those bad boys.

Also, nearfield ULF doesn't really work unless you're doing something truly insane.

Think about the response of a sealed system at your seat versus a close mic. Huge difference at 5Hz. By running them nearfield, you're essentially taking the room out of it.

If it were that easy, we'd all be running just a pair of high excursion 15's on the end tables on either side of our couch a few feet from our ears to give us 3Hz at reference. biggrin.gif

I hear ya, and I agree.

To match the GH/OH combo above 15hz, I'd need ~16 drivers in an IB with enough amp to max each driver out...not gonna happen. The horns just sound way too good smile.gif
lukeamdman is online now  
post #562 of 773 Old 10-17-2013, 10:59 PM
AVS Addicted Member
 
MKtheater's Avatar
 
Join Date: Jul 2006
Location: New Hartford, NY
Posts: 14,347
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 153 Post(s)
Liked: 421
It only takes one amp to run 8 and 8 is all you need to match the dual GH's. 20 hz has the biggest difference in spl and 8 FI IB3's would come very close to dual GH at 20hz. The rest of the bandwidth the 8x18 should have more output. There might be a couple frequencies where the dual GH's win but it would be too close to notice.
MKtheater is offline  
post #563 of 773 Old 10-18-2013, 09:22 AM
Bass Enabler
 
Scott Simonian's Avatar
 
Join Date: Oct 2001
Location: Clovis, CA
Posts: 13,447
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 291 Post(s)
Liked: 719
Build moar horns!

My Dual 18" LLT subs 120dB down to 10hz

 

Plan9Reloaded Co-host

Listen to the Plan9Reloaded Gaming and Technology Podcast (may contain NSFW language)

https://soundcloud.com/plan9reloaded/sets/podcast - direct pod link

http://plan9reloaded.com/site/ - main website

Scott Simonian is offline  
post #564 of 773 Old 10-18-2013, 09:48 AM
Senior Member
 
dsl1's Avatar
 
Join Date: Dec 2004
Posts: 419
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Quote:
Originally Posted by Scott Simonian View Post

Build moar horns!

6 more Ghorns.
dsl1 is offline  
post #565 of 773 Old 10-18-2013, 10:14 AM
FOH
AVS Special Member
 
FOH's Avatar
 
Join Date: Apr 2010
Location: Midwest
Posts: 4,747
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 208
Quote:
Originally Posted by LTD02 View Post

"it takes twice the swept area in an IB as one would otherwise need in a small sealed."

i'm wondering what you are thinking there as it would seem to go against the physics by which the two systems operate.

Not really, let me explain. It's what I call the IB powering conundrum.

LTD, much of this is review for you, but I'll cover this for everyone. IBs and small sealed are just so different. Clearly, the manner in which the box affects the driver's operation, via acoustic back pressure/air spring, is the primary mechanism of action differentiating them. The small sealed box acts like an acoustic high-pass filter, and this fundamentally changes the manner in which the driver's limits are encountered.


The small sealed box exhibits a vari-limiter characteristic ... protects the driver from excessive excursion as the frequencies go lower. The deeper the freq, the more back pressure up against the cone at peak travel. Thus, with a small sealed, you can have large amounts of power on tap both above and below the "knee" of the response curve, ... a very efficient use of the driver's limitations.


While a small sealed is thermally limited, an IB excursion limited. A theoretically superb approach, but it could use more amp power for complex material, .. but you need to power it according to it's limits at say 10hz. Now different driver bottoming characteristics may allow you to examine the powering a bit different. Fi's Xmax and Xmech are relatively close.


A proper IB isn't impacted by the box, thus it's very "bass efficient". An IB driver can often reach full excursion with a fraction of the power needed in a sealed system. The IB possesses other superiorities as well, but that's another discussion entirely. The Fi IB3-18s I have can handle about 300w@10hz, much more and they'll bottom. So I power them accordingly.


So, fundamentally the difference the way the power is utilized up against the driver limits. Now if the IB owner runs without a high pass filter, then the limit is above the knee. My 18" Fi's encounter their excursion limits about 300 watts or so @10hz. So wide open with no hi-pass, you're limited to a modest amount of power. Now, they'll play much louder with tons of impact with an hi-pass and much more power. However, that negates the wonderful, natural extension of an IB in the first place.

This is why there's more drivers needed with an IB system as compared to a typical small sealed ....

------------------------------------
Flat, Deep, Clean, Linear, and Loud
------------------------------------
Active 16.8kw, 7.3 system
(3)Seaton Cat12C up front, (4)QSC K8 sides/rears
(2)Seaton SubM-HP, (4)18" IB
FOH is online now  
post #566 of 773 Old 10-18-2013, 10:41 AM
FOH
AVS Special Member
 
FOH's Avatar
 
Join Date: Apr 2010
Location: Midwest
Posts: 4,747
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 208
Quote:
Originally Posted by lukeamdman View Post

From 13-100hz, I'm completely 100% satisfied.

Perhaps some Crowson transducers, actuating your seating/or seating riser. With proper time integration, it may be just what you're after.
Quote:
Originally Posted by nfraso View Post

So what would be the point? ..... Whatever you build to hit 5Hz is going to carry the rest just as well.

There is some merit to utilizing a distributed multi-sub approach above the room's first mode, and a single sub dedicated from that point downward. There's no multi-sub smoothing of FR benefit below a room's first mode.

Quote:
Originally Posted by nfraso View Post

Also, nearfield ULF doesn't really work unless you're doing something truly insane.

Think about the response of a sealed system at your seat versus a close mic. Huge difference at 5Hz. By running them nearfield, you're essentially taking the room out of it.

I understand your reference to close mic measurements, but at 10hz, and with wavelengths over 100', everything in the room is essentially nearfield.

I think the nearfield, rear IB is a valid approach, but I'm unsure about how many drivers it would take.


Quote:
Originally Posted by Scott Simonian View Post

I'd pay some VERY close attention to your signal chain if reproducing <10hz content is important. I'd do this before even thinking (well maybe not biggrin.gif) of putting in an IB system. Especially if it's point is to reproduce only 15hz and under.

^ ^ ^

Very important

------------------------------------
Flat, Deep, Clean, Linear, and Loud
------------------------------------
Active 16.8kw, 7.3 system
(3)Seaton Cat12C up front, (4)QSC K8 sides/rears
(2)Seaton SubM-HP, (4)18" IB
FOH is online now  
post #567 of 773 Old 10-18-2013, 11:01 AM
Bass Enabler
 
Scott Simonian's Avatar
 
Join Date: Oct 2001
Location: Clovis, CA
Posts: 13,447
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 291 Post(s)
Liked: 719
Quote:
Originally Posted by FOH View Post

Not really, let me explain. It's what I call the IB powering conundrum.

LTD, much of this is review for you, but I'll cover this for everyone. IBs and small sealed are just so different. Clearly, the manner in which the box affects the driver's operation, via acoustic back pressure/air spring, is the primary mechanism of action differentiating them. The small sealed box acts like an acoustic high-pass filter, and this fundamentally changes the manner in which the driver's limits are encountered.


The small sealed box exhibits a vari-limiter characteristic ... protects the driver from excessive excursion as the frequencies go lower. The deeper the freq, the more back pressure up against the cone at peak travel. Thus, with a small sealed, you can have large amounts of power on tap both above and below the "knee" of the response curve, ... a very efficient use of the driver's limitations.


While a small sealed is thermally limited, an IB excursion limited. A theoretically superb approach, but it could use more amp power for complex material, .. but you need to power it according to it's limits at say 10hz. Now different driver bottoming characteristics may allow you to examine the powering a bit different. Fi's Xmax and Xmech are relatively close.


A proper IB isn't impacted by the box, thus it's very "bass efficient". An IB driver can often reach full excursion with a fraction of the power needed in a sealed system. The IB possesses other superiorities as well, but that's another discussion entirely. The Fi IB3-18s I have can handle about 300w@10hz, much more and they'll bottom. So I power them accordingly.


So, fundamentally the difference the way the power is utilized up against the driver limits. Now if the IB owner runs without a high pass filter, then the limit is above the knee. My 18" Fi's encounter their excursion limits about 300 watts or so @10hz. So wide open with no hi-pass, you're limited to a modest amount of power. Now, they'll play much louder with tons of impact with an hi-pass and much more power. However, that negates the wonderful, natural extension of an IB in the first place.

This is why there's more drivers needed with an IB system as compared to a typical small sealed ....

Very well said, FOH. Much better than what I was ...attempting to respond with. I just gave up though. tongue.gif

My Dual 18" LLT subs 120dB down to 10hz

 

Plan9Reloaded Co-host

Listen to the Plan9Reloaded Gaming and Technology Podcast (may contain NSFW language)

https://soundcloud.com/plan9reloaded/sets/podcast - direct pod link

http://plan9reloaded.com/site/ - main website

Scott Simonian is offline  
post #568 of 773 Old 10-18-2013, 11:44 AM - Thread Starter
AVS Special Member
 
lukeamdman's Avatar
 
Join Date: May 2011
Location: Burnsville, MN
Posts: 1,328
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
Liked: 113
Quote:
Originally Posted by dsl1 View Post

6 more Ghorns.

HA! I don't need any extra output above 15hz...as you know, 2 Ghorns are literally destructive to a house.
lukeamdman is online now  
post #569 of 773 Old 10-18-2013, 05:06 PM
AVS Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 16,137
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 205 Post(s)
Liked: 921
"Not really, let me explain. It's what I call the IB powering conundrum."

you would be right...IF, the two systems were NOT eq'd for the same response.

once you EQ them for the same response, you are right back to being equal again because in both cases the excursion of the driver is what will limit the low end spl.

infinite baffle just gets there with less power.

not sure why this concept is so misunderstood?

Listen. It's All Good.
LTD02 is offline  
post #570 of 773 Old 10-18-2013, 05:15 PM
AVS Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 16,137
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 205 Post(s)
Liked: 921
for a sealed subwoofer of any size including infinite baffle...

the equation for displacement limited spl in 2pi space is empirical:

spl = 94.3 + 20*LOG(excursion/500) + 40*LOG(frequency) + 40*LOG(diameter/1000) + 6 dB

where,
excursion is in mm
frequency is in hz
diameter is in mm (effective piston diameter of driver)

infinite baffle get there with less power because they don't face the spring force of the air inside the enclosure, but don't have any advantage or disadvantage in spl relative to any other sealed design eq'd the same.

Listen. It's All Good.
LTD02 is offline  
Reply DIY Speakers and Subs

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off