The Paulinator said:
I assume you are talking to me..
The delta pro 12 inchers handle 400 Wrms, with efficiency at or about 100 dB spl. The cabs are sealed back, to help prevent xmax issues, and overexcursion as a result of a hydrogen/oxygen explosion... and the amp 50 hz high pass is also invoked.
Plenty loud enough for everything I've done, and capable of handling in their sleep, all my qscrmx 1450 can dish out (280wrms per channel into 8 ohms.) And, not too bulky for transport.
I never have to worry about destroying those 12 inchers with my amp... Ever..
My 18 year old borrowed a pair with one of my 1450's and a dual cd with mixer...and he cannot destroy them either.
Short answer: They are idiot proof, so that I will not blow them out..and loud..and not too bad sounding.
John
But I am really not planning on using a 12" speaker for a mid. I am hoping to use a few 8" drivers or something else that will go higher so I can take some duty off the tweeter. Selenium has 8's that go to 9000hz, I figure using 4 of those with a slot tweeter and a cross over point of about 7000 will do pretty good if there is a seperate subwoofer handling the dangerous stuff.
The Paulinator said:
I don't think it would be a good idea to take the 8" up that high as they would be to beamy by then. About 4.5 Khz absolute max if anything resembling even despersion with decent on & off axis tonal balance is a concern.
There's more to think about than just on axis response of drivers.
reply
If you want to use 8 inches as mids for pa then use Eminence Beta 8[3mm x max,225 w rms,2 inch vc on kapton former].
Have a look at this system below,the first pa system ever I've seen using 7 inch fibreglass and kelvar hifi mids!!!
Innerfield SoundSystem
http://www.brightonart.org/innerfield/index.html
😎
If you want to use 8 inches as mids for pa then use Eminence Beta 8[3mm x max,225 w rms,2 inch vc on kapton former].
Have a look at this system below,the first pa system ever I've seen using 7 inch fibreglass and kelvar hifi mids!!!
Innerfield SoundSystem
http://www.brightonart.org/innerfield/index.html
😎
Attachments
paulspencer said:They look like Scan Speak Kevlar 8" woofers
I never expected to see them used for PA!
If you look around all these teenageDJs you will find a lot of weird stuff that has been used for pa, with varying results...
Hmm, i heard of someone who wanted to build a pa out of 10w/4inch speakers not long ago 😉
electroaudio said:
I certainly wouldn't take advice from a crazy who would do that..🙄
And, 60 4 inchers with 96 3/4 dome tweeters: ya know how heavy that darn thing is gonna be??...I'm gonna be using a lot of 200 mil plywood with west system epoxy and maybe some glasscloth...try to actually engineer strength into it, rather than just toss wood at it..
Cheers, John
electroaudio said:
It was just a thought. I'm certainly not following through with that one. 😉
Besides, it was only gonna be the midrange section of a three-way, I still think it would be a credible design if I used enough of them.
My new idea is to take the mylar driver out of my Samsung cell phone and horn load it to increase the low end. I figure that should fill a small to medium size venue.
Paulinator,
I've finished my woofers. (Well, they're not upholstered yet, but they woof! 😀 )
The woofers (which are really midwoofers, since they'll cover the midrange OK, and they aren't real happy below 40hz--but this is PA, you don't need anything below 40hz.) play *VERY* well with my satellites, and using them, I've just had my first real "wow" moment with a set of speakers. After guesstimating time-alignment for the system, I played Fire and Rain, and holy $#!&, the speakers disappeared and James Taylor was right there in front of me.
The drivers are Parts Express #290-380, which are around $36 each, in a 2 cubic foot box vented and tuned to 40hz. If you want, I'll post the entire design of the box. Its exterior dimensions are only 13" wide x 14.5" tall by 22" deep. Tiny!!! They should be driven with 100 watts each and crossed over between 150 and maybe 2000 hz. These cabinets, all told, cost less than $50 each.
The satellites work out to less than $10 each, and are simply dipole mounting of Parts Express #269-912 (I like P.E. 😀 ), wired in series for 16 ohms, so I can parallel 4 of them and get huge amounts of coverage. Again, detailed design available if you want it. (Though this one's a pretty crummy design IMO. Needs to be redone!
)
So, for about $60 per side plus amplifier power and crossover components (I got my amps for free and would heartily recommend fully active biamplification) you can have some damn nice sounding speakers that will play 100 dB SPL and still sound damn nice. 😀
There, I answered your question. NOW WILL PEOPLE PLEASE STOP BICKERING ABOUT THE SENSITIVITY INCREASE OF MULTIPLE DRIVERS??!?! ;-)
I've finished my woofers. (Well, they're not upholstered yet, but they woof! 😀 )
The woofers (which are really midwoofers, since they'll cover the midrange OK, and they aren't real happy below 40hz--but this is PA, you don't need anything below 40hz.) play *VERY* well with my satellites, and using them, I've just had my first real "wow" moment with a set of speakers. After guesstimating time-alignment for the system, I played Fire and Rain, and holy $#!&, the speakers disappeared and James Taylor was right there in front of me.
The drivers are Parts Express #290-380, which are around $36 each, in a 2 cubic foot box vented and tuned to 40hz. If you want, I'll post the entire design of the box. Its exterior dimensions are only 13" wide x 14.5" tall by 22" deep. Tiny!!! They should be driven with 100 watts each and crossed over between 150 and maybe 2000 hz. These cabinets, all told, cost less than $50 each.
The satellites work out to less than $10 each, and are simply dipole mounting of Parts Express #269-912 (I like P.E. 😀 ), wired in series for 16 ohms, so I can parallel 4 of them and get huge amounts of coverage. Again, detailed design available if you want it. (Though this one's a pretty crummy design IMO. Needs to be redone!
)So, for about $60 per side plus amplifier power and crossover components (I got my amps for free and would heartily recommend fully active biamplification) you can have some damn nice sounding speakers that will play 100 dB SPL and still sound damn nice. 😀
There, I answered your question. NOW WILL PEOPLE PLEASE STOP BICKERING ABOUT THE SENSITIVITY INCREASE OF MULTIPLE DRIVERS??!?! ;-)
Well, you would get sound out of it anyway, Even if not so much that you would expect.
But wit a lot of gainclone amps in the boxes so maybe it would be useful for a hometheatre or maybe small gardenparties or something similar. 😉
I have also been thinking of a *cheap* linearray for myself.
Maybe this box could be a good startingpoint..
http://www.decware.com/whorn.htm
What do you think? Two mids on each side and some kind of treble on that, and each element is ofcourse powered with its own amplifier. 😉
*ROTFL*
But.. i doubt that it hasnt been done by some overenthustiastic djs before 😉
my idea isn't popular with the high efficiency crowd, but i like the idea of a "sweet sixteen" acoustic suspension 2 way using 8 x 8" midbass (planned on using 8 cabinets with 2 x 8" woofers back when sonicelectronix was offering free shipping on them) with some dirt cheap 8" woofers from MCM.
it gets REALLY annoying arguing with people who deny that ported woofers are simply distortion boxes TUNED to resonate to add bass. true, you get louder & deeper bass, but it's just resonant distortion EXACTLY like the distortion your breath creates when you blow across a bottle & excite it's resonant frequency. even when you show port lovers the facts (FROM SPEAKER MANUFACTURERS THEMSELVES EVEN), they will just cling to their illusion that ports can do no wrong when they also add time delay to the bass as well as less control of the woofer than a tight air spring.
acoustic suspension is the best solution for sound quality. it sacrifices efficiency and extension for clarity. by using multiple drivers, you get "free dB" using the "you get 3dB every time you double the number of drivers you use" rule. with 8 drivers per side (you REALLY need to know how to wire for impedence!) you get 9 extra decibles for any given driver as well as an increase in power handling as well.
using 8" drivers for midbass gives you a much quicker midrange than using 10" or larger PA drivers as well as punchier bass because of the air spring effect. it's the best solution to boomy one note bass (i despise ported speakers and never heard TIGHT & undistorted bass until hearing a friend's pair of 4 1/2" infinity 2 ways back in the 80s before they sold out to "duh... me like it loud" fidiots who buy speakers based on quantity of sound and not quality. sure, i couldn't feel the bass, but what was there was unbelievably free of distortion and was what started my hifi junkie obsession. the clear tight bass & superior imaging that smaller speakers offer are still my favorites short of the lightning fast unboxy sound of planars.
the other hideous tradeoff for efficiency that PA speakers maker are horns which are notorious for "honking & sizzling" as they add distortion in the form of reflections caused by the walls of their horns much like the resonances induced by porting. there are no free meals, when you try to add something that isn't there to sound, it comes at a price. if you absolutely MUST go with a horn mid or tweet, waveguides offer the least distortion, but i'm inclined to believe that the small 2" "titanium bullet" tweeters that are especially popular with high efficiency SPL drag racers in the car audio scene offer the best HF clarity with high efficiency as they use the smallest horns. they'd also offer better dispersion than beamy horns.
to me, just using the same principles that make a $120 pair of minimonitors sound punchier and less distorted than multi-thousand dollar klipshes are the best solution for ultimate fidelity in a PA system. the only reason you don't see such systems being offered is because they'd be very big & expensive to make.
haters would whine that such a system would suffer from "comb distortion effects" that would make such a speaker unlistenable, but i say that's BS because concert PAs scatter drivers (especially tweeters) over huge areas and horns also add time delay to a system which is a form of distortion too unless you carefully align the drivers.
i've heard decent sound from a club PA that put three cabinets side by side with the tweeters 3 feet or more apart and THAT'S where you're most like to get comb filtering, in the highs where wavelengths are shortest. to all of the "comb filter whiners", it's funny that the laughably huge "treme treme" systems with dozens of tweeters & woofers like this one CAMINHAO TREME TREME!!! - YouTube or this one RACHA DE SOM EM PARANAVAI-PR - YouTube don't sound as bad as many muddy PA systems i've heard and with a scaled down minimonitor approach with just 1 tweeter per side, you could easily get a nice 95dB+ system with 500w or so power handling that would be way more than you'd need for anything short of a concert.
here's a pic of the mockup i made with a 6 foot tall character for scale
the system was designed to attack all of the the hideous resonance distortions & compromises of large PA systems and get as close to minimonitor sound as possible with the added flexibility of breaking the system down into 4 speakers and making the smaller components much lighter & easier to lift.
in watching the latter "treme som" video, i didn't hear ANY comb filtering effects that would cause the EQ to change radically as the camera moved around, but DID hear the effect in a club where they stacked a pair of towers on top of each other with the tweeters about 3 feet apart causing a really shrill & biting sound which i pointed out to the sound tech with the suggestion of rolling the highs off a little and flipping the top tower so the two tweeters are closer together which they did after the show and the sound improved greatly. just using one tweeter (or an array of closely spaced ones) would cure the worst effects of potential comb filtering.
anyways... that's my "thinking outside the resonant box" idea that ALSO adds lower cabinet vibration as smaller modules are pretty much the same thing as massive internal bracing versus the box resonances in plywood or *cringe* plastic PA speakers.
to me, those 2 treme treme systems sounded flatter and less boomy than a lot of PA speakers driven hard like one club's 15"ers that were so boomy and distorted, i couldn't recognize "jam on it" for sure in the intro.
i just can't stand the boomy & sloppy sound of ports (though a really well designed system like B&W isn't as bad as a really bad 1 note bass one) or the sluggishness of larger subs (to me, planars have the absolute least colored bass even if they roll off) or the spitty & harsh sound of horns, so this is my solution to high dB with the fewest SQ compromises.
as the system would be more expensive than i can afford right now, i'll start out with a pair of 2x10" cabinest with 95dB accordion woofers and the same pyle tweeter in the mockup and sacrifice some midrange clarity for the sake of getting gigs asap. i already have my 4x12" subs and a 500w class D plate, so making people feel the bass at a party won't be an issue and 4 more 10" in full range mode won't hurt the bass any either.
it's a shame that custom woodworking is so expensive and shipping costs more than off the shelf boxes practically.
it gets REALLY annoying arguing with people who deny that ported woofers are simply distortion boxes TUNED to resonate to add bass. true, you get louder & deeper bass, but it's just resonant distortion EXACTLY like the distortion your breath creates when you blow across a bottle & excite it's resonant frequency. even when you show port lovers the facts (FROM SPEAKER MANUFACTURERS THEMSELVES EVEN), they will just cling to their illusion that ports can do no wrong when they also add time delay to the bass as well as less control of the woofer than a tight air spring.
acoustic suspension is the best solution for sound quality. it sacrifices efficiency and extension for clarity. by using multiple drivers, you get "free dB" using the "you get 3dB every time you double the number of drivers you use" rule. with 8 drivers per side (you REALLY need to know how to wire for impedence!) you get 9 extra decibles for any given driver as well as an increase in power handling as well.
using 8" drivers for midbass gives you a much quicker midrange than using 10" or larger PA drivers as well as punchier bass because of the air spring effect. it's the best solution to boomy one note bass (i despise ported speakers and never heard TIGHT & undistorted bass until hearing a friend's pair of 4 1/2" infinity 2 ways back in the 80s before they sold out to "duh... me like it loud" fidiots who buy speakers based on quantity of sound and not quality. sure, i couldn't feel the bass, but what was there was unbelievably free of distortion and was what started my hifi junkie obsession. the clear tight bass & superior imaging that smaller speakers offer are still my favorites short of the lightning fast unboxy sound of planars.
the other hideous tradeoff for efficiency that PA speakers maker are horns which are notorious for "honking & sizzling" as they add distortion in the form of reflections caused by the walls of their horns much like the resonances induced by porting. there are no free meals, when you try to add something that isn't there to sound, it comes at a price. if you absolutely MUST go with a horn mid or tweet, waveguides offer the least distortion, but i'm inclined to believe that the small 2" "titanium bullet" tweeters that are especially popular with high efficiency SPL drag racers in the car audio scene offer the best HF clarity with high efficiency as they use the smallest horns. they'd also offer better dispersion than beamy horns.
to me, just using the same principles that make a $120 pair of minimonitors sound punchier and less distorted than multi-thousand dollar klipshes are the best solution for ultimate fidelity in a PA system. the only reason you don't see such systems being offered is because they'd be very big & expensive to make.
haters would whine that such a system would suffer from "comb distortion effects" that would make such a speaker unlistenable, but i say that's BS because concert PAs scatter drivers (especially tweeters) over huge areas and horns also add time delay to a system which is a form of distortion too unless you carefully align the drivers.
i've heard decent sound from a club PA that put three cabinets side by side with the tweeters 3 feet or more apart and THAT'S where you're most like to get comb filtering, in the highs where wavelengths are shortest. to all of the "comb filter whiners", it's funny that the laughably huge "treme treme" systems with dozens of tweeters & woofers like this one CAMINHAO TREME TREME!!! - YouTube or this one RACHA DE SOM EM PARANAVAI-PR - YouTube don't sound as bad as many muddy PA systems i've heard and with a scaled down minimonitor approach with just 1 tweeter per side, you could easily get a nice 95dB+ system with 500w or so power handling that would be way more than you'd need for anything short of a concert.
here's a pic of the mockup i made with a 6 foot tall character for scale
the system was designed to attack all of the the hideous resonance distortions & compromises of large PA systems and get as close to minimonitor sound as possible with the added flexibility of breaking the system down into 4 speakers and making the smaller components much lighter & easier to lift.
in watching the latter "treme som" video, i didn't hear ANY comb filtering effects that would cause the EQ to change radically as the camera moved around, but DID hear the effect in a club where they stacked a pair of towers on top of each other with the tweeters about 3 feet apart causing a really shrill & biting sound which i pointed out to the sound tech with the suggestion of rolling the highs off a little and flipping the top tower so the two tweeters are closer together which they did after the show and the sound improved greatly. just using one tweeter (or an array of closely spaced ones) would cure the worst effects of potential comb filtering.
anyways... that's my "thinking outside the resonant box" idea that ALSO adds lower cabinet vibration as smaller modules are pretty much the same thing as massive internal bracing versus the box resonances in plywood or *cringe* plastic PA speakers.
to me, those 2 treme treme systems sounded flatter and less boomy than a lot of PA speakers driven hard like one club's 15"ers that were so boomy and distorted, i couldn't recognize "jam on it" for sure in the intro.
i just can't stand the boomy & sloppy sound of ports (though a really well designed system like B&W isn't as bad as a really bad 1 note bass one) or the sluggishness of larger subs (to me, planars have the absolute least colored bass even if they roll off) or the spitty & harsh sound of horns, so this is my solution to high dB with the fewest SQ compromises.
as the system would be more expensive than i can afford right now, i'll start out with a pair of 2x10" cabinest with 95dB accordion woofers and the same pyle tweeter in the mockup and sacrifice some midrange clarity for the sake of getting gigs asap. i already have my 4x12" subs and a 500w class D plate, so making people feel the bass at a party won't be an issue and 4 more 10" in full range mode won't hurt the bass any either.
it's a shame that custom woodworking is so expensive and shipping costs more than off the shelf boxes practically.
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You mean, people actually argue with you? I can't think why ...
Not a good choice of words. Ported boxes have lower distortion than sealed. Yes, they do add group delay, but that should be understood within the context of the larger room effects. You can clearly see differences in measurements when the room is taken out, but once you take a listening position measurement, you can't tell if it's sealed or vented at all. Even if you have a heavily treated room, and those who complain about issues with vented boxes almost never do, the room is still doing more harm. Each room mode is like a port, except the problems are magnified many times. So you have to understand the differences in a real world context, not from an anechoic chamber perspective.
I've heard vented boxes that sounded very good, and sealed boxes with no chance. It's not a simple matter of vented boxes being evil.
As with all things audio, it's not quite so simple. Once you factor in extension, SPL and cost, all kinds of solutions present themselves. Do you spend $600 for two drivers in a sealed box? Or do you get one better driver in a vented box? I know you weren't considering all things in that one statement but when it comes to making a choice, we have to consider all kinds of things. If cost were no object, then I'd probably consider IB to be the ultimate. You meet your output targets with brute force, choose the best quality drivers, install them around the room for a multi sub arrangement and tick all the boxes. None of this is really budget minded.
Can't agree there. The size of the drivers is just a means to an end in the bass. I'm more interested in the motor of the drivers, acoustic treatment and how they are integrated. You do need to start with decent quality bass transducers, but a fairly ordinary driver properly integrated into an acoustically treated room will beat an exceptional driver poorly integrated in a bad and untreated room. In the midrange as well, there is a lot more to it than driver size.
You can get compression drivers and waveguides to sound very good indeed and they solve a lot of problems for pro use. Start with say a good sounding compression driver like B&C DE250, put it on one of the better waveguides like the popular QSC, or SEOS or there is also a Pyle waveguide that is dirt cheap, measures well and sounds good. I found adding reticulated foam helped a great deal as well. Not sure it's the way to go for pro audio though, if it gets used in a pro setup. Pair it with one of the better quality pro midbass drivers and instead of using a pile of cheap drivers, a smaller number of better quality ones. Not too expensive, but very good sounding if set up right.
driver size DOES have a direct impact on any driver's speed and extension. it's simple physics. bigger & heavier is going to be slower. if you deny that, then you haven't done a lot of reading of speaker reviews or technical papers. the only reason to go with bigger drivers is for bass extension and of course to move more air more efficiently. a bunch of smaller drivers with the same surface area will have similar, if not more efficiency without as much mass to move "per voice coil". there's a reason that many listeners, including myself, prefer the sound of minimonitors besides their superior imaging.
there's NO WAY acoustic suspension has MORE distortion than ported! i need to look up one of the sites that describes the pros & cons of each design. i think MTX has one, but there are many. maybe it was kicker. here's their list of ported cons at this address Intro to Enclosures | KICKER
which are all just ways to say the add sound that shouldn't be their to the signal while there are NO distortion cons to acoustic suspension. that's from a speaker manufacturer's website, they have much better resources for verifying these facts and deep trained staffs & designers that try to maximize SQ behind those statements. if anyone wants to argue the point, take it up with them and any other site that tells it like it is. i'm just reporting the facts... facts which my own ears verified until i learned the science behind WHY infinity minimonitors got me all worked up the way no larger ported speaker could... tight thump with no resonance or overhang or as the brits would say... superior pacing.
though they don't mention less bass extension or lower efficiency which are easily remedied with either more drivers, or more power and maybe some EQ. the bottom line is it's easy to get back what you lose with acoustic suspension, but impossible to get rid of the RESONANCE artifacts that ported woofers add. if you look the subject up, another site mentions the very same "blown bottle" resonant mode effect that's behind the dreaded "on note bass" effect.
i can accept the fact that many people prefer that big bloated boomy sound, but not that they refuse to admit that it's a form of distortion. it's resonance and EVERY ported speaker is TUNED to a resonant frequency. you can try to deny the facts a 100 ways, but they'll still remain facts. one system is about quality and the other quantity.
here's another confirmation of THE TRUTH at Essay
which is pretty much EXACTLY what i've said.
if you REALLY want the best SQ, you have to give up another 3dB efficiency to use the "push pull" (aka nestorovic) design which offers even better woofer control in smaller boxes
acoustic suspension is a sound (pun intended) route to the best SQ in a conventional system and the way to increases it's efficiency, as you called it, is the "brute force" method meaning you'll need a lot of drivers and a much bigger enclosure to match the output of a high efficiency driver in a ported or even *gasp* horn loaded scoop.
air springs just give better driver control and a tighter, clearer "thumping bass" with no more boom than whatever resonances are in a flimsy box or from standing waves which would also be there in a similar quality box that's ported, but without the RESONANCE (distortion). the speed and clarity of a 4 1/2" sealed minimonitor's bass walks all over a big 15" ported woofer, but of course it won't move as much air. i'll take clarity over louder distortion every time
you also mentioned cost with a sweet sixteen system, but 8 x 8" poly woofers that sell for just $8 or so in quantity are actually CHEAPER than most pro audio woofers that start at $50 for a 10" and that go up into the $300 range. the biggest cost then becomes building a larger (or more) cabinet(s). if you're out for ultimate SQ, (or SPL for that matter) you have to accept the compromises for whichever route you take. there are no free meals though ported fans wouldhave you believe their are and have deep seated denial generally as i've argued with many who refuse to acknowledge widely known facts either out of ignorance, or simply defensive lying or delusions that "because i like that sound better, it can't be a form of distortion".
the truth will set you free.
here's a THIRD site that tells it like it is: http://www.caraudio.com/forums/enclosure-design-construction-help/400271-enclosure-design-pros-n-cons-good-read.html
regarding acoustic suspension...
and regarding ported designs...
i've always favored "boomy" as the best description myself
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boy oh boy!
Am i glad i didnt whale into this 'discussion'....
Very few car audio sites have much credence in my experience and offer an over simplified explanation for those who assimilate knowledge without understanding, or those who dont wish to learn but want a flash calculator to tell them the answer...
Who else would spend their life savings on a 1farad cap to make their 12v car battery MORE dc than it is already....
Am i glad i didnt whale into this 'discussion'....
Very few car audio sites have much credence in my experience and offer an over simplified explanation for those who assimilate knowledge without understanding, or those who dont wish to learn but want a flash calculator to tell them the answer...
Who else would spend their life savings on a 1farad cap to make their 12v car battery MORE dc than it is already....
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budget, you have an irritating way of pushing your point, but it appears you've made up your mind without considering everything involved. You're only looking at a part of the picture.
I'm not denying anything. It's not as simple as you present. You can't isolate driver size and mass of the cone from the motor that drives it. Nor can you consider any of this in isolation of the room itself.
Do the technical papers and reviews that you mention show measurements that back up your points, or do they simply put some dot points about pros and cons?
There are some actual tests here, including sealed and vented versions of the same driver:
Index to Subwoofer Tests by Manufacturer/Model - Home Theater Forum and Systems - HomeTheaterShack.com
The trend that I have seen with vented is that the distortion is lower. Sealed subs can have low distortion down to about 40 Hz, but it tends to creep up very high below that. Vented versions can extend low distortion down to the tuning point.
That is not what is being said here.
I have not denied this at any point, but I have mentioned that you have to consider this in relation to the bigger picture, ie the real performance in the room and what is actually audible. You are isolating this aspect from the real conditions that exist in a room. Things aren't all quite so simple, nor are they black and white. Vented boxes aren't all boomy, they can perform very well if implemented correctly. You can get clean articulate bass from vented subs. You may not have experienced it, but it certainly is possible. I'm far more interested in how room modes are damped, how the room is treated and how the bass system of choice is calibrated, measured and set up. If a system has poor bass, it will normally be due primarily to those things not being done right, rather than simply choosing a vented design over sealed. Or that the drivers are poor to begin with. If you use a lot of cheap drivers, there is some risk that they have poor motor systems and it doesn't matter how well you treat the room and integrate things then, you won't get past the weaknesses of a cheap motor.
It is true that a port does introduce ringing. However, this is masked by room modes. Recently I took some measurements of a bandpass woofer nearfield. The decay is far more rapid than you see when the room response is taken. The vent is not the bottleneck, the room is. Even in my room with very large bass traps, this is true.
You are choosing to focus on only part of the truth.
The irony of this is that despite your protests that others are in denial, it is you who are most in denial because you are focusing very narrowly on only part of what is going on. There are many who see ported boxes as just another set of compromises with potential to perform in an accurate system.
Looking at one of the links you posted, is the author in denial too?
Far more interesting than sealed vs vented is how you integrate the bass in your system:
http://www.hifizine.com/2011/06/bass-integration-guide-part-1/
(Yes, that's an article that I wrote recently). You will see in-room behaviour. If you have a sealed box, such as I've measured in there, you can also get ringing related to using EQ to extend response. The decay behaviour starts to look like a vented box!
I'm not denying anything. It's not as simple as you present. You can't isolate driver size and mass of the cone from the motor that drives it. Nor can you consider any of this in isolation of the room itself.
Do the technical papers and reviews that you mention show measurements that back up your points, or do they simply put some dot points about pros and cons?
There are some actual tests here, including sealed and vented versions of the same driver:
Index to Subwoofer Tests by Manufacturer/Model - Home Theater Forum and Systems - HomeTheaterShack.com
The trend that I have seen with vented is that the distortion is lower. Sealed subs can have low distortion down to about 40 Hz, but it tends to creep up very high below that. Vented versions can extend low distortion down to the tuning point.
That is not what is being said here.
I have not denied this at any point, but I have mentioned that you have to consider this in relation to the bigger picture, ie the real performance in the room and what is actually audible. You are isolating this aspect from the real conditions that exist in a room. Things aren't all quite so simple, nor are they black and white. Vented boxes aren't all boomy, they can perform very well if implemented correctly. You can get clean articulate bass from vented subs. You may not have experienced it, but it certainly is possible. I'm far more interested in how room modes are damped, how the room is treated and how the bass system of choice is calibrated, measured and set up. If a system has poor bass, it will normally be due primarily to those things not being done right, rather than simply choosing a vented design over sealed. Or that the drivers are poor to begin with. If you use a lot of cheap drivers, there is some risk that they have poor motor systems and it doesn't matter how well you treat the room and integrate things then, you won't get past the weaknesses of a cheap motor.
It is true that a port does introduce ringing. However, this is masked by room modes. Recently I took some measurements of a bandpass woofer nearfield. The decay is far more rapid than you see when the room response is taken. The vent is not the bottleneck, the room is. Even in my room with very large bass traps, this is true.
You are choosing to focus on only part of the truth.
The irony of this is that despite your protests that others are in denial, it is you who are most in denial because you are focusing very narrowly on only part of what is going on. There are many who see ported boxes as just another set of compromises with potential to perform in an accurate system.
Looking at one of the links you posted, is the author in denial too?
Far more interesting than sealed vs vented is how you integrate the bass in your system:
http://www.hifizine.com/2011/06/bass-integration-guide-part-1/
(Yes, that's an article that I wrote recently). You will see in-room behaviour. If you have a sealed box, such as I've measured in there, you can also get ringing related to using EQ to extend response. The decay behaviour starts to look like a vented box!
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