best 18” drivers that can go flat 20Hz

lots of music has content below 26hz.

If you listen to electronic, 10hz is not uncommon.
it is felt and create a presence hard to describe, removing it remove a vital element in the experience.

you do not think there is energy down there till you have a system that can do it and realize how much you missed all those years...

to have the effect, one have to listen bit loud, human ear can't hear 20hz unless it is at least ~80db (as per research on ear sensitivity)
since subsonic content is often 20 decibel down in the recording, one have to listen to 100db or so to get the intended effect...

Very much so. It's a bit like a tweeter. Sure, you don't need it to understand there is music being heard, but it enhances the realism of the experience. Real music, in person, has a great deal of low end content that tends to be forgotten when the primary mode of consumption is hearing through PA stacks (filtered for the sake of logistics) or albums that are recorded for the lowest common denominator of playback system. Getting a good sub going in my system after years of relegating it to home theater purposes was most enlightening when I played my first good recording and realized how much more real the experience felt; the instruments finally had body that put them in the room rather than sounding like something played through a radio. It's too bad that we overlook that element considering as audio enthusiasts we don't let the dictates of pop recordings determine what we do with our setups else we'd be listening to Beats Pills and calling it good.

Without mentioning that Human hearing is close to non existent at that level... ie; down 60db at 20 hz.
More than pointless ...despite all Brochure babbles and shills.

That really should go without mention since it's misleading for you to say that. Repeating misinformation does not make it reality. Let's see what those ol' PhDs have to say about what the ear actually hears:

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Ah, interesting. Actual research shows audibility at realistic levels for live music, that infrasound is heard far before it's felt and that as the sound level approaches that of music playback, the lowest frequencies draw closer to parity with midrange and, most interestingly, small increases (once above background body noise) sound significantly louder than the rest of the audio band. So, if you can reproduce the lowest frequencies at musically important levels as encountered in real life, they contribute to the listening experience.

This research, however, is SPL based. Other papers (that I can't find the article for at the moment, frustratingly, and that I had saved on my dead computer, not this one) indicates that the ear starting at 100Hz and significantly below 40Hz becomes dominated by particle velocity level over sound pressure in the sound intensity equation. That PVL sensitivity at low frequencies produces nerve impulses upwards of ten times the intensity such that, in one case, the in ear canal sound pressure sensor was registering negligible readings at the bottom of the transducer sweep while the probe on the nerve was showing some of the highest readings of the run. So, the contour curves may not be wholly representative given that they are only derived from sensors measuring only half of what's going on at the lower bass frequencies.

It's too bad the shills for speakers that can not reproduce low frequencies have had so much sway in what's taken as common wisdom in this hobby. Just earlier I was reading an article from '51 by Klipsch that touched on the 50Hz argument (and another of that vintage that put it up as high as 200Hz!) and the fallacy of it. All these decades later and people are still the same figuring if something's hard, it mustn't matter. It strikes me as intellectual laziness.
 

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.......That PVL sensitivity at low frequencies produces nerve impulses upwards of ten times the intensity such that, in one case, the in ear canal sound pressure sensor was registering negligible readings at the bottom of the transducer sweep while the probe on the nerve was showing some of the highest readings of the run. So, the contour curves may not be wholly representative given that they are only derived from sensors measuring only half of what's going on at the lower bass frequencies.....
I wonder if that explains the epidemic of permanent hearing loss in the generation exposed to dance and electronic music that creates those delicious massive low frequency visceral vibes?

Its a bit ironic when so many have put so much money and time into enjoying beats that has sent them partially deaf. :(
 
I wonder if that explains the epidemic of permanent hearing loss in the generation exposed to dance and electronic music that creates those delicious massive low frequency visceral vibes?

Interesting question. The articles I've seen on that, though, have attributed it more to headphone/earbud wearing having become so prevalent among the youth since the iPod and smartphones made listening to music and being seen listening to music everywhere so much a personal statement and downright fashion choice courtesy Apple's advertisement campaign focusing on those white earbuds of theirs. Seems some of the younger generation never take theirs out/headphones off if they can help it and it's difficult to gauge how loud music is being listened to after awhile when so isolated from external cues.
 
.......The articles I've seen on that, though, have attributed it more to headphone/earbud wearing..
Yep, that makes total sense and completely explains the hearing loss epidemic amongst the young. Thanks.

).... Stereo Integrity .. custom 24" units .... to use in some open baffle speakers I'm getting around to building at a glacial pace...
That looks like its going to be fun. Do you think OB bass sounds different then pressurising the room with subs? I wonder if OB bass might replicate acoustic instruments well but not be able to do electronic infra-sounds?
 
I like the pressure thump that sealed cabinet subs can deliver. In a small room it can be unpleasant though at high level. Pressurization happens below room's lowest mode, typically below 30Hz,so it very much depends on room dimensions and wall construction/absorption. Room shape and typical added acoustic panels have no effect. Room's modal analysis/simulation is helpful, to find optimal positiong of speakers and the listener. One must remember to analyze modes in 3D.

More info http://media.tas.zeitpress.com/articles/images/TAS197_Bass_Figure3.jpg

This means that actually there is no need to make (= eq) the woofer to have straight response to 20Hz in nearfield measurements! We get 3-6dB boost in almost every domestic room at 20Hz.
An externally hosted image should be here but it was not working when we last tested it.
 
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I like the pressure thump that sealed cabinet subs can deliver... We get 3-6dB boost in almost every domestic room at 20Hz.

Great explanation thanks. Looks like sealed subs rule under 30Hz for electronica thrills. Could p!ss the neighbours off but.


A Guide To Better Bass (TAS 197) | The Absolute Sound


Check out Fi audio in Las Vegas (made to order in U.S.A).

These guys have excellent subwoofer drivers---mostly geared to car audio but can make almost anything you need. NOT cheap but a quality product.

Nice tip thanks. Fi woofers with 33mm Xmax and looks that are deadly. Made in Les Vegas!
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WOW Diogenes,

quite the extensive reply on the bass audibility
the vibration perceived from the body, everybody know this intuitively but the ear PVL, I never knew about that aspect. This is gold, will research more on this.

I know that probably 95% of people claim that bass below (25-35hz being the common answer) ain't important, those peoples always happen to have a system that barely do 35hz flat and never experienced or shown an interest in digging deeper... they are just happy to "presume they know"

Ignorance is bliss and I just do not have energy to convert them one by one with long post and argument.

I had a few people that came to my room,and smiled at my claim of being flat down to 7hz. (calibrated microphone confirmed)
they usually tell me that I'm wasting money on driver/amp for nothing.
Being 100% active with DSP, I can test them and put a "brickwall" filter at any point of their choosing.
they usually pick somewhere between 25-32hz to insert the brickwall.

they listen to whatever they want to for a while.
--->when I remove the brick wall, their face change... "they suddenly see the light"

Love this, love it, love it, love it.
Thanks you very much for your unscientific opinion about bass, your face at the end of this "test", you just made my day:)


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To go back on the OP question.
few subwoofer will do 20hz cleanly.
most 12,15 or 18 size are optimized for higher frequency.
it is a tradeoff between playing very low and being able to play high (for a sub).

A 20hz capable woofer will have require a strong magnet, need good excursion and have an low fs. (usually, 18-21hz resonant frequency, 25hz and above FS won't work very well, 30hz FS, just forget it)
Unfortunately, this also mean an heavy cone, limited sensitivity and high voice coil inductance.
those required parameter also limit subwoofer output to less than 100hz. (if you're lucky)

in the 12", the classic perless XXls come to mind first.
they can go up to roughly 70hz
SBA does their equivalent in the SB34xxx series.
SBA also have a 15: version that would work.

10", I would just not even bother. they are too much SPL limited.
you would need 15 of them... (bass array maybe)

I use Mach 5 IXL 18" myself.
being 18", they move a lot of air but they can't do much more than 60hz
I use mine 7-45hz but I also use 6 of them as a single one can't do much output at 7hz without distorting like crazy... (shopping for another pair too)

If you where hoping for a 20-500hz capable subwoofer, I do not know any that does it great. Nor I think physic would allow such feat.
The Scan Speak 32W revelator serie will come close but they break up hard at ~800hz and I would limit them to 350hz, they also cost quite a bit.
pushing them down to 25hz and below ain't a good idea, I know, I owned a pair... and sold them.
28-30hz is ideal for them IMHO.

Good luck.
 
My subwoofer dilemma and solution.

i have a medium size room that is 16.5' wide x 25' long with 10' ceiling height. I have a 4 way horn system consisting of Classic Audio 2" exit field coil drivers (beryllium pgrams) in 26 " Sierrra Brooks solid mahogany tractrix horns for low mids, custom field coil driver (Jeffrey Jackson) with JBL beryllium 3" pgrams on a 13" wood tractrix horn for upper midrange and TAD ET-703 tweeters. The midbass uses a pair of Altec 515b's in parallel per channel in a straight 70Hz. Hypex horn designed by Dr. Bruce Edgar and built by me.

In my room, the response of the mid bass horn was flat from 58hz to 400Hz. This system gives about 108 db for 1 watt power. Finding the "best" subwoofer of reasonable size that would blend well and keep up with the horns was a real challenge !!!! I tried pair of Aura 1808's in a large vented enclosure--sounded slow and not well defined in the below 30hz. range. I tried 2 pairs of Adire Tumult 15' drivers in both sealed / DSP and vented enclosures----sounded very good but still thought better could still be had. The cats meow turned out to be a pair per channel of TC Sounds LMS 5400's 18" drivers ( 80+ lbs. each ) 30+mm of Xmax in dual opposed sealed 9.5 cu ft. enclosure, heavily braced with 3" thick baltic birch front and rear baffle and 2.25" sides, top and bottom.

I used a pair of Crown I-Tech 5000 HD amps strapped to mono for power (3000+ watts on tap per sub). These Crown amps have a damping factor of 2000+ for absolute control of the aluminum diaphragms. These amps also have built in crossovers, DSP and dozens of other functions for pro audio use. The crossovers were set to 60hz. and roll off at 48db per octave. To say these subs are awesome IMHO is an understatement. The subs were eq'd flat from 12hz to 60hz and 100++db at 12hz--and CLEAN. This system can reproduce a nearly live drum kit in my room !! These subs match the horns, are extremely articulate, low distortion, and POWERFUL beyond words. My friend and I actually got "sick" while setting the low eq frequencies !! The cones only move about 18 to 20mm at insane (DANGEROUS) power levels. Just make sure any dental work is securely fastened !!!

The quality of your subwoofers DOES matter in the 30hz to 60hz range---more than most people think !!! I was very sad when I heard from Parts Express that TC Sounds was out of business. These are the best subs I have ever heard. I don't know if a better sub driver exists today. This subwoofer solution was very expensive but worth every penny to me. Good luck to those seeking the ultimate subwoofers !!
 
I have only two Seas LROY26 10" sealed woofers in my 30m2 living room and they are just fine. When they start cloncking I get some 110dB at 2OHz at spot. Enough for me, my typical listening level is below 90dB peak. Still, more Sd would be better for sure.
 
etalon90: It's not that stuff below 25-35hz is not important, there is most certainly a benefit from getting bass below these frequencies. But like with everything else for us with the "audio upgrade frenzy", be certain that you will actually gain something from delving deeper. Which is why I suggested actually analyzing the specific individuals music collection first, to get an idea of the potential benefit.

Just generalizing here, so there will be room for the ocassional oddball exception: House music does not gain anything from below 35hz. Rock/metal does not gain anything from below 35hz, maybe except a few live albums, or some studios that have no hp on the kick, then again other rock/metal recordings have little under 60hz even. Drum'n'bass, there are some very few that have good output to 30hz, but not many. There are some electronica genres that focus heavily on very low frequency sound, but I am seriously questioning the intent of this, is it really motivated from the urge to see speaker cones flap around? Not saying it's of no benefit, just questioning the intent behind the music.

The biggest benefit I've seen is with: Well done but rather basic setup jazz recordings. Full classical orchestra. Pipe organs. Piano. NOT from the sounds the instruments make, but it adds realism because you get a very profound sense of the SPACE.

Other than that, there is a number of recordings where vocalist technique can be very annoying, like when they say the letter "p" directly into the diaphragm of the microphone. Or just plain breathing into it. We all make mistakes, but this is not a problem on small speakers.
 
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Thanks guys for all the responses-it was illuminating but a bit confusing.I realize the PA460 can't give me what I want unless I make it work very hard through the active DSP and with distortion as well as the need for a huge box-260liter which I'm not keen on !

The UM18-22 is capable of going down to 20Hz ,but needs a very powerfull amp due to it's lack of efficiency and has some distortions .It's also quite competitive to SI 18HT and TC Sounds LMS-5400 which both models are not manufactured anymore(the latter brand is out of business at all) My wish is to use an internal tube amp class A but such an amp with 500w-1000watts might cost me arm and leg ,unless there are some Kits for sale that can deliver it at reasonable price accordingly-I'm clueless about it and appreciate any advice.

Furthermore,I prefer a reputable 18' or 15' driver from well known brand ,regardless the price,provided it corresponds the data and performance I'm looking for in such a driver.It must have a tight clean bass without any distortion through all it's frequency range from 20Hz and up with very good BMX and Fs and excellent Fs inside the box which must be not too big since the designated wall is 3.5meter with 2.7meter ceiling .

Any advice would be highly appreciated.
 
I must admit that I don't fully understand the difference between infinite baffle and sealed enclosure and pro's and con's of each one in comparison to the other.Regarding the AESpeakers you recommended-it's Xmax and efficiency are not to die for and it's frequency range is obscured like many speakers of this brand.
If I had a plan/sketch of some nice conical/exponential horns out ofwhich I could place the subwoofer driver with it-I'd do it instantly without any hesitation and would be grateful if someone could send me such a plan. The Mach 5 audio driver seems very capable driver ,although I've never heard it nor know it's cost.
 
I use the AE TD15S in 170lt 30hz BR and get a nice 24hz in room. I don't know what music or loudness you like but a 250watt SAE amp with heavy metal is too loud. The 15S would like a bigger box yet.

Depending on how high you like, one of the Faital pro 1.4 drivers with Eighteensound 1.4 horn crossed at 700hz would work very well and be simple but not cheap. Add a ribbon above for a nice three way and you may be done. I know I am. LOL

I like bass that doesn't need a sub. Makes the design much easier.