For those who have listened to IB subs.... - Page 4 - AVS Forum
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Old 06-15-2010, 06:31 AM
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So where does the rotary sub come into play? A lot of talk about which is "best", but there is no talk about best/price/situation. Seems like it depends on your budget and placement options. Also, as has been said before, there really is no best. They are just different, with different advantages. A rotary will get me more spls at a low frequency, but with a IB I could also take a trip to the Bahamas, Europe, and Asia.

<$400 = horn and gets you to 15-20 hz
<$2k = IB and gets you to 5-10 hz
$5k (no idea) = sealed?
20k = rotary sub and gets you to 1 hz

...and depends on room size

limited room = sealed subs
very limited HT room, but another "spare" room = IB or rotary
more room = horn

renting an apt = sealed or horn or butt kickers

Current HT: HTPC-->Epson 5010 projector-->135" screen, BFM TLAHs x7 & THT
Build log: DIY rotary sub for contemporary HT in 100 year old house?
Andreas' Slow Rotary Sub build
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Old 06-15-2010, 07:54 AM - Thread Starter
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The rotary sub comes in when you have a hell of a lot more money than I ever will. I'll look into one if I ever win the Lottery
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Old 06-15-2010, 10:08 AM
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Quote:
Originally Posted by AndreasMergner View Post

So where does the rotary sub come into play?

A rotary sub will go flat all the way to 1 Hz with very high output. I've seen one demoed (I can't say I "heard" it demoed, since the effect wasn't audible, but doors and windows rattled). IB subs will get you to 10 Hz or even down to single digits, but not that "ultimate" extension (although still better than anything but a rotary).
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Old 06-15-2010, 12:20 PM
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Originally Posted by RyguyOK View Post


As far as my needs go, to get huge displacement, hit as low as possible , and keep the budget reasonable(less than $1500) IB sounds like the best contender, yes? Are there sealed options that can get similar results within that price range? I assume Bossobass's setup is a bit beyond my budget....

Not sure why everyone thinks there is some huge dollar leap from IB to sealed in boxes.

Build 2 subs, each with dual opposed AV15H drivers and power each with a Behringer amp. You're in budget, you've significantly upgraded from what you have and the system will perform on a par with an 8xIB15 system.

The difference between 500W and 2000W is +6dB with next to no cost difference. Not sure how that turns into thousands of dollars and tons of power, but there you go.

The cost of materials and hardware for the current 10KW amplification, stackable 8X15", Bassis-controlled system I'm currently building is $3400. Considering it's flexibility, size, looks and immense power, I don't see what all the fuss about cost is.

You might want to pick one and start a thread with room dims and get real input from those who have what your after instead of keeping this generic thread open.

Bosso
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Old 06-15-2010, 01:13 PM
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Quote:
Originally Posted by bossobass View Post

Not sure why everyone thinks there is some huge dollar leap from IB to sealed in boxes.

Build 2 subs, each with dual opposed AV15H drivers and power each with a Behringer amp. You're in budget, you've significantly upgraded from what you have and the system will perform on a par with an 8xIB15 system.

The difference between 500W and 2000W is +6dB with next to no cost difference. Not sure how that turns into thousands of dollars and tons of power, but there you go.

Bosso

Now you've confused me. So please help me understand your point. I was under the impression that displacement was far and away the main thing to consider when comparing sealed systems(correct me if I'm wrong about that). A pair of subs each with a pair of AV15H's would have around 15L of displacement while(and I'm just picking a brand that's popular for ib use) 8 Fi 15" subs would have about 38L of displacement. I'm far from being any kind of expert so seriously help me understand why these two setups would be similar.
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Old 06-15-2010, 01:18 PM
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Quote:
Originally Posted by bossobass View Post

Not sure why everyone thinks there is some huge dollar leap from IB to sealed in boxes.

Build 2 subs, each with dual opposed AV15H drivers and power each with a Behringer amp. You're in budget, you've significantly upgraded from what you have and the system will perform on a par with an 8xIB15 system.

The difference between 500W and 2000W is +6dB with next to no cost difference. Not sure how that turns into thousands of dollars and tons of power, but there you go.

The cost of materials and hardware for the current 10KW amplification, stackable 8X15", Bassis-controlled system I'm currently building is $3400. Considering it's flexibility, size, looks and immense power, I don't see what all the fuss about cost is.

You might want to pick one and start a thread with room dims and get real input from those who have what your after instead of keeping this generic thread open.

Bosso

If you have the room and wife approval I agree with bosso on the sealed system. The flexibility to co-locate and tweak locations is great.

However if you (or wife) don't want the boxes showing 4 IB18s, one Ep2400/4000 + eq is going to be about the same price (depending on the eq you choose). If you can borrow subs to play with you can tweak locations. Then build two manifolds with 2 IB18s in each and put them exactly where you need.

The huge plus for me in an IB was not so much SQ as spl and low end extension while achieving a happy wife. The SQ is just a side benefit compared to the 2 ported 12s I had.
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Old 06-15-2010, 01:32 PM
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Quote:
Originally Posted by bossobass View Post

Not sure why everyone thinks there is some huge dollar leap from IB to sealed in boxes.

Build 2 subs, each with dual opposed AV15H drivers and power each with a Behringer amp. You're in budget, you've significantly upgraded from what you have and the system will perform on a par with an 8xIB15 system.

The difference between 500W and 2000W is +6dB with next to no cost difference. Not sure how that turns into thousands of dollars and tons of power, but there you go.

The cost of materials and hardware for the current 10KW amplification, stackable 8X15", Bassis-controlled system I'm currently building is $3400. Considering it's flexibility, size, looks and immense power, I don't see what all the fuss about cost is.

You might want to pick one and start a thread with room dims and get real input from those who have what your after instead of keeping this generic thread open.

Bosso


There is a small different. Yes, its the same number of drivers but the difference is the $$$ needed for more powerful amps and a better EQ.

To drive my 4 18" woofers in sealed boxes I would need 3 more amps instead of one EP2500 and a more expensive EQ.

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Old 06-15-2010, 01:34 PM
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Originally Posted by cmryan821 View Post

Now you've confused me. So please help me understand your point. I was under the impression that displacement was far and away the main thing to consider when comparing sealed systems(correct me if I'm wrong about that). A pair of subs each with a pair of AV15H's would have around 15L of displacement while(and I'm just picking a brand that's popular for ib use) 8 Fi 15" subs would have about 38L of displacement. I'm far from being any kind of expert so seriously help me understand why these two setups would be similar.


The comparison should be 8 15" woofers in sealed boxes vs 8 15" woofers in an IB designs. or 4 15" in sealed boxes vs 4 15" in an IB. You must keep the displacement equal to have a real comparison.

In the end with good EQing and more amp power the sealed design will equal the IB in pretty well all audio measurements.

The difficulty here is having 4 boxes in room with dual 15" woofers.

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Old 06-15-2010, 04:18 PM
 
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Originally Posted by penngray View Post

The comparison should be 8 15" woofers in sealed boxes vs 8 15" woofers in an IB designs. or 4 15" in sealed boxes vs 4 15" in an IB. You must keep the displacement equal to have a real comparison.

In the end with good EQing and more amp power the sealed design will equal the IB in pretty well all audio measurements.

The difficulty here is having 4 boxes in room with dual 15" woofers.

In a dedicated room that should not be a problem. Seating should never be against the back wall so there should be room in the back for two and there should be room for two up front with the mains. Now in a family room it certainly could be challenging. The poster above talked about building a couple IB's with two drivers each. You could also use those same locations for building sealed subs. You loose placement flexibility, but gain no intrusion in the room. You will not get as much output, but you also will not have the back wave to deal with. Like I said before there are a lot of different ways to get there (good bass) no one way is better. There is no good, better and best solution that applies in all situations. In my HT room I could be happy with multiple sealed subs, multiple ported subs, multiple horns or a couple IB's. I listed more than one because I do not like single sub solutions, no matter how good they are.
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Old 06-15-2010, 04:49 PM
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Quote:
Originally Posted by penngray View Post

The comparison should be 8 15" woofers in sealed boxes vs 8 15" woofers in an IB designs. or 4 15" in sealed boxes vs 4 15" in an IB. You must keep the displacement equal to have a real comparison.

In the end with good EQing and more amp power the sealed design will equal the IB in pretty well all audio measurements.

The difficulty here is having 4 boxes in room with dual 15" woofers.

That's pretty much what I had always thought, and that's why I was so confused when Bosso stated that a 4x15" setup would be equivalent to an 8x15" setup. I know the AE drivers are very well thought of but that seemed like alot of difference to make up.
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Old 06-15-2010, 05:02 PM
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Originally Posted by bossobass View Post

Would you mind showing me where the drivers are loafing at single digits in your penciling-out process?

Bosso

Below the lowest room mode (about 22 Hz in my room), and if the room is perfectly sealed (mine isn't), the formula for dB SPL all the way down to 0 Hz (DC) is:

dB SPL = 194 + 20*log(Vdriver/Vroom)

My room is a bit under 3000 cu.ft. so I need a bit over 1 cu.ft. of 1-way driver Vd to hit 125 dB down low. That's a bit over 3 liters for each of the 8 drivers and that takes very little power in an IB. Obviously you can't hit 0 Hz in most rooms but getting below 10 Hz isn't that hard, even if the room is really leaky. So, yeah, the driver is getting an excursion workout down low but it's probably doing it with less than 100 watts so that's what I meant by 'loafing.'

Dennis H
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Old 06-15-2010, 05:10 PM
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Originally Posted by cmryan821 View Post

Now you've confused me. So please help me understand your point. I was under the impression that displacement was far and away the main thing to consider when comparing sealed systems(correct me if I'm wrong about that). A pair of subs each with a pair of AV15H's would have around 15L of displacement while(and I'm just picking a brand that's popular for ib use) 8 Fi 15" subs would have about 38L of displacement. I'm far from being any kind of expert so seriously help me understand why these two setups would be similar.

That's why I said to pick an alignment, post room dims and get specific. They're too many cooks in this soup. Cat mentioned 8X15" with 800W power & Penn mentioned 4X18" with similar power.

If you prefer to use the Fi drivers and get full use of the larger displacement, then you're gonna need way more amp.

The AV15H has far higher sensitivity than the IB drivers and in a small sealed box you can get the most out of them by having enough power on tap and not worry about driving them to pieces below the knee.

That adds up to a big swing above the knee, so yes, 4 of them with 5kw will easily best the 8X15 IB with 800W above 30Hz.

Below the knee, the drivers and amp need to be specified, the room needs to be specified and we can discuss comparisons with some degree of accuracy.

Bosso
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Old 06-15-2010, 05:13 PM - Thread Starter
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Quote:
Originally Posted by bossobass View Post

Not sure why everyone thinks there is some huge dollar leap from IB to sealed in boxes.

Build 2 subs, each with dual opposed AV15H drivers and power each with a Behringer amp. You're in budget, you've significantly upgraded from what you have and the system will perform on a par with an 8xIB15 system.

The difference between 500W and 2000W is +6dB with next to no cost difference. Not sure how that turns into thousands of dollars and tons of power, but there you go.

The cost of materials and hardware for the current 10KW amplification, stackable 8X15", Bassis-controlled system I'm currently building is $3400. Considering it's flexibility, size, looks and immense power, I don't see what all the fuss about cost is.

You might want to pick one and start a thread with room dims and get real input from those who have what your after instead of keeping this generic thread open.

Bosso

I'm sorry if I offended you with my question. Your current build is more than double my planned budget.... I'm sure it will outperform the options I'm looking at. I have nothing against sealed, I was just under the impression that to get the performance of a decent IB would require a larger budget.

I apologize if I gave the impression that I was ready to build now. Part of the reason for starting this thread was to get a better idea of the options available and their performance to budget ratio. That it has done. I'm not ruling out multiple sealed, because you've pointed out that there's a better chance of reaching my goals this way than I had thought. I can't give room dimensions yet because I've pretty much decided to go with something towards the top end of my budget. This means, unfortunately, that it's gonna have to wait till I move to a new place. I'm gathering intel so I can try to be ahead of the game when the time comes to finalize.

I'm immensely grateful for all the useful info I've gained from this thread. You guys are all very patient with someone who only has a (very) basic grasp of building my own HT gear. There's a lot to learn. I appreciate the help, all :
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Old 06-15-2010, 05:38 PM
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Originally Posted by RyguyOK View Post

I'm sorry if I offended you with my question. Your current build is more than double my planned budget.... I'm sure it will outperform the options I'm looking at. I have nothing against sealed, I was just under the impression that to get the performance of a decent IB would require a larger budget.

I apologize if I gave the impression that I was ready to build now. Part of the reason for starting this thread was to get a better idea of the options available and their performance to budget ratio. That it has done. I'm not ruling out multiple sealed, because you've pointed out that there's a better chance of reaching my goals this way than I had thought. I can't give room dimensions yet because I've pretty much decided to go with something towards the top end of my budget. This means, unfortunately, that it's gonna have to wait till I move to a new place. I'm gathering intel so I can try to be ahead of the game when the time comes to finalize.

I'm immensely grateful for all the useful info I've gained from this thread. You guys are all very patient with someone who only has a (very) basic grasp of building my own HT gear. There's a lot to learn. I appreciate the help, all :

Sorry, I attempt to be as brief as possible and give the wrong impression often as a result.

I don't mean pick one to purchase, I mean pick one to speak specifically about it without all the chatter that's usually involved in an open forum thread.

Penn,

What do you mean by 'better EQ'? Same EQ for either, IMO.

Bosso
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Old 06-15-2010, 05:46 PM
 
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Quote:
Originally Posted by RyguyOK View Post

I'm sorry if I offended you with my question. Your current build is more than double my planned budget.... I'm sure it will outperform the options I'm looking at. I have nothing against sealed, I was just under the impression that to get the performance of a decent IB would require a larger budget.

I apologize if I gave the impression that I was ready to build now. Part of the reason for starting this thread was to get a better idea of the options available and their performance to budget ratio. That it has done. I'm not ruling out multiple sealed, because you've pointed out that there's a better chance of reaching my goals this way than I had thought. I can't give room dimensions yet because I've pretty much decided to go with something towards the top end of my budget. This means, unfortunately, that it's gonna have to wait till I move to a new place. I'm gathering intel so I can try to be ahead of the game when the time comes to finalize.

I'm immensely grateful for all the useful info I've gained from this thread. You guys are all very patient with someone who only has a (very) basic grasp of building my own HT gear. There's a lot to learn. I appreciate the help, all :

You can go pretty cheap no matter what type of alignment. I have less than $1,700 in four sealed subs (12" TC Sounds, 12" Shiva-X, 12" TC Sounds and 18" Maelstrom-X) powered by three pro amps. All items were new except for the Maelstrom. A larger IB would probably go lower and louder, but I doubt I and my 1,250 CF room could take anymore in my room.
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Old 06-15-2010, 05:51 PM
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Quote:
Originally Posted by bossobass View Post

That's why I said to pick an alignment, post room dims and get specific. They're too many cooks in this soup. Cat mentioned 8X15" with 800W power & Penn mentioned 4X18" with similar power.

If you prefer to use the Fi drivers and get full use of the larger displacement, then you're gonna need way more amp.

The AV15H has far higher sensitivity than the IB drivers and in a small sealed box you can get the most out of them by having enough power on tap and not worry about driving them to pieces below the knee.

That adds up to a big swing above the knee, so yes, 4 of them with 5kw will easily best the 8X15 IB with 800W above 30Hz.

Below the knee, the drivers and amp need to be specified, the room needs to be specified and we can discuss comparisons with some degree of accuracy.

Bosso

Ok that makes a little more sense. I missed the part of the discussion earlier that would have the 8x15" ib using only 800w. I read your post as a stand alone statement about 4 15" sealed subs comparing very well to 8 15" subs in an ib alignment and it was quite confusing. My mistake.
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Old 06-16-2010, 01:36 AM
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The guys with the ported subs say sealed subs sound no better.

The guys with the sealed subs say an IB is no better than sealed.

The guys with the IB's say nothing sounds like an IB
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Old 06-16-2010, 05:28 AM
 
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Originally Posted by Jesse S View Post

The guys with the ported subs say sealed subs sound no better.

The guys with the sealed subs say an IB is no better than sealed.

The guys with the IB's say nothing sounds like an IB

And the reason for that is because they are not comparing apples to apples. How many IB owners went from a sealed system that could provide the same bass response as the IB system? I bet that number is zero. They made an upgrade in their bass and choose an IB system for that upgrade. Does not mean that they could not have gotten there using another method or combination of methods.
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Old 06-16-2010, 05:49 AM
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Quote:
Originally Posted by Jesse S View Post

The guys with the ported subs say sealed subs sound no better.

The guys with the sealed subs say an IB is no better than sealed.

The guys with the IB's say nothing sounds like an IB

What about the guys that have them all??

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Old 06-16-2010, 05:53 AM
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Quote:
Originally Posted by bossobass View Post

Penn,

What do you mean by 'better EQ'? Same EQ for either, IMO.

Bosso

Doesnt a sealed design need a proper LT circuit? since the box rolls off the natural response of the driver much higher.

An IB can be EQed by a simple 1124p and a Good sealed design needs sometihing like the DCX2496.

Maybe "better" wasn't a good term..how about More complex EQ?

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Old 06-17-2010, 01:01 AM
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Hahaha... I step out for a bit and things really head for the crapper. Gotta love AVS.

bosso, I don't even know were to begin.

Let's try this one more time. A little drier.

All you are talking about is FR, and EQ. Let's think about this...

If you pull a driver out of a sealed enclosure, and stuff it into a horn it will not sound the same. IE, the FR (among other things) will be different. It's the same with different sized sealed enclosures as well. If there wasn't a different sound in reality you wouldn't need the EQ to adjust the FR to begin with, right?

That is all there is to it.

You can not say something does not exist, and then say that you can EQ the FRs all to sound the same. If there was no difference to begin with, why did you have to add EQ to them? That is insanity.

As per your post 55, 1) I know you were calling me out with your initial post. That was a joke. 2) Show me exactly where I am off in that interpretation. After this post it seems to ring even more true. Which is sad. (I notice you didn't use "Q" again though.)3) Your charts, and stories of other peoples lives hace no relevance to the subject at hand, and only further shows a flawed grasp of the total concept at hand. As for your numbered questions (and the rest,) I will assume they were a poor attempt at humor this time.

My exact words were
Quote:


If you ignore space and cost factors, and just go on SQ they are great. By SQ I mean playback uncolored by the enclosure (and driver in some cases.)

Now have you ever taken a driver measurement on a test baffle? That is as close to the raw drivers response as you are going to get. Anything else is extra or a coloration on top of the drivers response. Now which enclosure can give you that same output raw? Not counting room issues/influences, as those will effect any sub you place in it, including a naked driver. It's not just FR it's everything else as well.

If anyone doesn't know, look up the spec sheet on a driver, or a measurement from one of the well know DIY guys. Now simulate a proper IB with said driver. If you do it right they should null out. The end.

I am not trying to push an alignment on anyone, unlike others. There is no opinion in the original statements you seem to have had a problem with. You also seem to think that I said someone should prefer one over the other, which is not true. SQ has nothing to do with what someone will like. Most people love the sound of my Logitech computer sub, and it has really awful SQ. It thumps like mad though, on everything you throw at it.

Now if you can find something false in this post please feel free to correct it. I only ask that you use quotations, and limit the discussion to the incorrect portion(s) only. I don't care about what so and so said before in a different context, what you feel are the limits of different alignments, or the strengths of your own personal subs.
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Old 06-17-2010, 11:51 AM
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It's bothering me. I can't let it go. Why exactly are you trying to turn this into an IB vs bosso thing anway?
Quote:
Originally Posted by bossobass View Post

Getting back OT, there are 4 disadvantages to the IB vs a boxed sealed system; 1) when the ambient temperature can vary from 45 degrees to 130 degrees, performance is affected. E-mail Ilkka and ask him what comparative value his measurements would have if the ambient temp varied that much from test to test. 2) An IB can't properly use the corner(s) of a room. 3) Placement tweaks are not possible. 4) Mid bass potential must be limited or HP filter protection must be employed, there's no getting around it.

--Steve has had a lot more to add to the hobby than your condescending blurts.

1) I guess you couldn't possibly install an IB in anything other than an attic, if one was worried about this. Oh yeah, what is your "ThruVent Cooling" about again? Do I need to quote you talking about temperature increases in "high powered" sealed subs.
2) Yeah, I tend to forget about IBs changing the laws of physics. There is no possible way to get an IB wave to bounce off of more than two boundaries at the same time. Let alone place it close enough to be within a quarter wavelength of a corner.
3) This is a bit petty, but ok I'll play. You could move it around as many times as you want. It just takes more work. If you followed he recommended way of doing things it isn't a big deal though.
4) What are you taking about? It is the same as any other sub. You are always limited by lowend displacement, and power handling somewhere. There are many ways to play that tune, and no way around it for any sub.

I don't remember saying anything about anyone's personal contributions value/worth/merit to any "hobby" in any capacity about myself, or anyone else. Try reading my words for what they say, and not add colorations to them.

EDIT: That should read, "(and/or) power handling somewhere."
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Old 06-17-2010, 01:13 PM
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Quote:
Originally Posted by bossobass View Post


Lower freqs have a longer decay time, regardless of alignment. One cycle at 40Hz is 25ms and one cycle at 10Hz is 100ms. All else equal, this will be reflected in decay times of different FRs.

Bosso

I know you're trolling but let's look at this slightly differently.

One cycle at any particular frequency has little, or nothing, to do with SQ. They do not exist in isolation even in very large, organ, flue pipes. The difference is easily heard with an IB.

Every tone has a beginning, a middle and an end. Are you arguing that the attack, sustain and decay are identical for every subwoofer with a matching FR? Or just that you can't hear any difference in the way organ pipes begin to speak? How they hold their tone, waver, rise or fall? How they each decay in their own completely individual way? Often it has hardly time for a single 16hz sinewave to get out of bed let alone have its first coffee and cigarette.

Displacement has nothing to do with SQ. Displacement is merely insurance against bottoming. It is a waste by-product... unless you desperately need cone movement for air cooling your multi- kilowatt, pumping station.

Cone area matters far more than displacement where SQ matters. Wave a postcard by a full yard back and forth. Now wave an 8' x 4' panel by a tiny fraction of a millimetre. Their displacement is identical. Which size do you prefer for the reproduction of your favourite 32' ranks of organ pipes?

Hint: The postcard is a very poor impedance match with the air.

Small cone area with high displacement stirs the air violently. Large cone area with small excursion tightly controls the air movement with gentle finesse. Leading edge, sustain and decay.

The flapping, long-throw cone punches right through the air. Shadow boxing without impact. The air moves aside and around the pummelling fist.

A large surface area does not allow the air to flow around the outsides. It produces a perfect wave front. Why else would instruments and animals which speak very low be made very large? Leading edge, sustain and decay. Nature abhors the minuscule with deep voices. It doesn't know whether it's coming or going!

Imagine the form of a long sound wave. A huge, incredibly-lightly-inflated, sausage-shaped bubble.

Hit it with a small, hard punch and your hand goes right through. As if there were nothing there. That's your silly, flapping cone.

Now get your 8'x4' and see how you can make and move balloons as rapidly as you like. You have total control.

EQ-ing a subwoofer to get more bottom end power, than nature intended, is a violation of these principles. The cone must move violently to keep up the acoustic output with falling frequency.

Compare yours to our 8 x 15" (or larger) IBs. The cones never move. We have the equivalent of a bass electrostatic membrane. What the geniuses can't achieve with huge, megabuck electrostatics we do every single day with one hand behind our backs on a 1000 watts. The money you spend on electricity buys our DVDs and CDs.
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Old 06-17-2010, 01:34 PM
 
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I'm glad that Soho54 decided to change his signature after I skewered it ten ways from Sunday because it was an embarrassment to the Readership. After all, who wants Robin Hood as their inspiration ? Especially in a serious discussion about IBs. I suppose he could have ended his sig with : "The ferry man decided to tip his merry hat to the merry children and was a merry man" but that would seem a tad bit cheesy but no more cheesy than the original.

Anyways, back to the endless bickering...

PS Anyone who can put 1+1 together understands full well that ChrisBee was summoned here by the Cult ...by someone....and I have my suspicions as to who that someone was.

Howdy ChrisBee, it's been a long time. How have you been ? I thought you decided to ditch the other 4 15" woofers in your IB because the amount of raw displacement was not needed. If you decided to keep them then good on you, since everyone knows that there is no replacement for displacement
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Old 06-17-2010, 01:50 PM
 
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Quote:
Originally Posted by ChrisBee View Post

The flapping, long-throw cone punches right through the air. Shadow boxing without impact. The air moves aside and around the pummelling fist.

One could argue that multiple sealed subwoofers offering the same displacement factor as an equivalent IB would offer similar impedance matches to the air so then the radiation impedance (wow...that's a big word...) will be identical to the big IB system with 8 15" cones when you have smaller box subwoofers, but more of them.

So then, using my amazing linguistic power, the rate of decay and sustain and the flutter of a mocking bird will be just as delicate as the mighty IB, since the displacement and the impedance match to the air will be identical.

The bass was stomp you, take your breath away, then, in an instant, move your soul, while moving you, your skin, taking you to the depths of hell and back, all in one brilliant moment of ecstasy.

Am I getting somewhere close ?
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Old 06-17-2010, 01:55 PM
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Looks like this may turn into an internet junk punching fiesta...


ChrisBee,

I am not sure what you are trying to convey with your post because it is not making sense to me, atleast with regard to the subject at hand. One can assume that everyone here is thoroughly versed in the advantages of cone area AND long throw. Displacement. No one needs a hypothetical scenario comparing a multiple driver IB to something like a single small sized 12" or 15" sub. Comparisons like that are absurd. Obviously something having 6 or 8X the cone area will have a distinct advantage. You mention a small long throw driver futilely punching at the air but it has no bearing on the discussion. We are comparing the sound of different alignments having a similar amount of cone area of the same 15-21" driver sizes as would be involved in the IB's. Think multiple 15's or 18's or perhaps very large horn loaded enclosures. Either way the IB does not have the inherent cone area/displacement advantage that it almost always enjoys when it is compared to other subs for the purposes of this enclosure SQ difference discussion. We are comparing an 8'x4' to another 8'x4' of different material construction in effect. If you prefer that analogy.

The IB will require virtually the same amount of driver induced "violent air stirring" as the other alignments being compared against it as a 4x18" sealed system and a 4x18" IB will require the same amount of excursion to reproduce a 16hz tone at the same level. A 4x18 ported, bandpass, or horn set-up will require equal or LESS driver excursion than the IB as long as the signal is at or above the knee.

This includes the effects of EQ too. EQ does not alter the amount of excursion, or amplifier power required for a specified output at a given frequency. It only modifies the signal.

Again Bosso would be comparing 8x15 to the 8x15 IB you mentioned so the cone movement would be the same for both systems. There is no advantage there. The IB advantage is in low freq efficiency.

BTW,

I would have an IB if I had the right set-up for it.
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Old 06-17-2010, 02:10 PM
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Dear eleven year-old. (goneten)

Still suffering from vocabulary envy and attention seeking, I see.

Anyway, I wasn't summoned. I read that the great unwashed were arguing about completely the wrong issues and thought I'd better put my oar in.

Now repeat after me: Take as much time as you need.

Displacement is voice coil insurance.

You are freely exchanging displacement with cone area. This, despite the two being distinctly different things. (no matter how intimately they are related)
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Old 06-17-2010, 02:12 PM
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goneten, I'm watching you, and tuck in that shirt.
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Old 06-17-2010, 02:21 PM
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Ricci

I was pointing out that most of you were arguing about completely the wrong things.

The discussion seemed to revolve around IB versus the rest of the world. The OP asked to be convinced of the merits of IB. He requested no discussion about small boxes and one's own private, cola-fired power station.

I used what little command I have of the English language to persuade the OP that he would find pleasure in the soft arms of an IB.
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Old 06-17-2010, 02:21 PM
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EDIT: Ignore this post. The word "specified" in the quote was let out in my mind.
See post 132 for the realization.

Quote:
Originally Posted by Ricci View Post

EQ does not alter the amount of excursion, or amplifier power required for a specified output at a given frequency. It only modifies the signal.

This is off. Adding EQ can alter the amount of amplifier power required for a specified output at a given frequency.

Lets go 1 to 1 here. One RS 15" in an IB at 10xVas will require 1w for 73dB at 10Hz.
One in a sealed enclosure of 3cu ft will need 7 more watts worth of power to do the same after the FR is EQed.

Edit: Let's add to this. It is not the EQs fault exactly, that it takes more power, but the enclosures. Either way, if you add with an EQ you are asking for more power. Cutting asks for less.
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