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Giant Sub-Woofer
PuceBaboon sent us linkage to an amusing story about building a
gigantic custom sub woofer. I was about to yawn until I looked at the pictures of them excavating a 60 cubic meter hole, and laying bricks. This one might be a little outside the realm of reasonable, but it's damn impressive.
The question I have is, "why?" Is the guy making up for some other "shortcoming"?
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
Howard Stern would have a field day with this puppy!
Oh man.. that room with Motorhead's Boneshaker DVD and some Fort Garry Dark Ale.
All that'd be left are greasy, bloody smudges.
I can hardly wait for someone to put it in their car, and drive through my neighborhood at 3 am...
There in lies the secret to cold fusion
What those apparently puddles of yellowish brown liquid in the pics near the bottom are? Just how powerful is this thing anyway?
This MUST be old news. From the looks of the shwank pad, it must be the 70s. This is where pot will get you. Making giant subwoofers. Oh wait... pot will get you sleeping on the couch or laughing about things that aren't funny.
Nevermind.
...scientists are predicting Southern California could be in for a major earthquake this spring or summer.
Hotblack quated as saying, "You call that a woofer??"
Free Mac Mini Yeah, it's
...setting up for a "Disaster Area" gig!
----------------------------------- My Other Sig Is Hilarious -----------------------------------
I've built my own speakers before, and while you can do a good-enough job without too much hassle, making a first-rate product is very labor and math intensive. If this guy is putting that much money and effort into this project, I really hope he gets all the damping and power equations right. Otherwise this will all just be a publicity stunt (maybe that's what it is anyway). I'm thinking about the amplifier he needs to run it right now. That's a lot of juice! And juice = money. And worste of all, you'd never be able to use the thing! Even a store bought stereo goes well above the municipal noice ordinances. And bass carries the furthest! What is this guy thinking?
If he ever does use it, I bet he'll feel that really cool thumping sensation in his chest though.
Slashdot Syndrome: the sudden, extreme urge to correct someone in order to validate one's self.
The main question is, does it go to eleven?
The CB App. What's your 20?
where do i plug in my guit?!
this is awesome. really, incredibly oversized and inappropriate - but absolutely awesome.
I hope I didn't brain my damage.
The Hitch Hiker's Guide to the Galaxy notes that Disaster Area, a plutonium rock band from the Gagrakacka Mind Zones, are generally held to be not only the loudest rock band in the Galaxy, but in fact the loudest noise of any kind at all. Regular concert goers judge that the best sound balance is usually to be heard from within large concrete bunkers some thirty-seven miles from the stage, whilst the musicians themselves play their instruments by remote control from within a heavily insulated spaceship which stays in orbit around the planet - or more frequently around a completely different planet.
Their songs are on the whole very simple and mostly follow the familiar theme of boy-being meets girl-being beneath a silvery moon, which then explodes for no adequately explored reason.
Many worlds have now banned their act altogether, sometimes for artistic reasons, but most commonly because the band's public address system contravenes local strategic arms limitations treaties.
This has not, however, stopped their earnings from pushing back the boundaries of pure hypermathematics, and their chief research accountant has recently been appointed Professor of Neomathematics at the University of Maximegalon, in recognition of both his General and his Special Theories of Disaster Area Tax Returns, in which he proves that the whole fabric of the space-time continuum is not merely curved, it is in fact totally bent.
So what happends when this guy blows a subwoofer speaker? He has the speakers under 1 ton of marble if I read it right. That's not a very accessible configuration for maintenence.
A giant subwoofer made with a wooden speaker cone soaked in sake?
> As an audiophile myself ...
> I have competed in IIASCA sound competitions
You seem to be contradicting yourself.
All your BASS are belong to us
Isn't it interesting how you come to recognize posters based solely on their sigs???
Too many non-neutral colors for critical viewing. This is also impressive for people who believe tubes are the only way to go, yet tubes aren't known for neutral rendering or good bass response and horns aren't known for smooth response either. I'd say this may be the largest and most efficient home subwoofer (who knows) of its capability but I doubt it's the best. I use 12 18" BagEnd subs in a concrete chamber beneath my home theater. That a 3KW amp does the trick nicely and extends every bit as low as this job.
Speaker guy: Is there a problem officer?
Policeman: The neighbors are throwing up. Can you please turn down your gigantic, crater-filling sub-woofer?
Speaker guy: Huh?
"All great things are simple & expressed in a single word: freedom, justice, honor, duty, mercy, hope." --Churchill
Richard Clark's "Bread Truck" subwoofer
Here's a guy who designed and built a custom driver to compete in car stereo SPL competitions. The driver was built to be mounted in the box of an old bread truck. It was driven by 2 custom 10,000 watt amplifiers.
Unfortunately, one giant sub doesn't always work as well as several smaller ones, because he didn't win squat with this setup. However, it's not like he needed to prove anything to those in the car stereo world (check out some of the tech briefs on their Main Autosound2000 website)
Overrated / Underrated : Moderation
...like this?
the standing waveform that was once Nikola Tesla makes the harmonic that now passes as its smile.
I've heard Hotblack Desiato used a black hole as a subwoofer at the galaxy twist gig next saturday.
Fans whom have will heard it claims:
-It really rocked!
Warning: This sig contains a small bug. ==> *
The neighbors must be thrilled!
For every post, there is an equal and opposite re-post.
Would you dare sit at this listening point? Is this where the Spanish Inquisition positions the comfy chair?
proof, n. A demonstration that a conclusion is implied by certain premises and axioms.
Yea, I'm pretty sure Ellisons old lap pool beats those guys: http://sanfrancisco.bizjournals.com/sanfrancisco/s tories/2003/07/21/focus1.html?t=printable
A candidate for the "bored with extreme wealth" category, though not yet a grandpa, is Oracle CEO Larry Ellison. When he revamped his Pacific Heights home a few years ago and wanted to eliminate a lap pool on the bottom level, Green convinced him to turn it into a massive subwoofer instead.
Green said that when he and Ellison played Jurassic Park to test the system "the part with the dinosaur stomping actually lifted us up out of our seats. (The sound) was moving eight inches of concrete" on the floor.
This text is filler, because apparently my per line character rating is too low. Hopefully it's an average, so this fluff will bring it up. Please fix Slashcode so that this crap isn't a problem. I have sincere doubts that it does any good to stop the trolls (browse at -1 if you don't believe me). So why torture your other readers/posters by making them jump through the troll hoops?
Overrated / Underrated : Moderation
For having the gigantic subwoofer and having mandolin music on the giant TV screen.
A far better screenshot would have been "Apocalypse Now" or even a "Quake" game.
bun-fhuinneog agam!
I hate to nit-pick, but it's a large, elaborate enclosure and not a huge subwoofer itself. Slightly more practical is the "Cult of the Infinitely Baffled".
y .h tml
http://home.comcast.net/~ttriff//page2IB-Galler
No shit!
RTFA. It's a horn subwoofer, not a cone. Compression is achieved using 8 10" woofers - not one big one. I do agree with you though - I can't imagine how this could sound good.
Negative feedback is used in transistor amplifiers to eliminate even harmonics (2X 4X 6X) that your ear hears as distortion. The downside is that it also eliminates odd harmonics (1X 3X 5X) that pianos and acoustic guitars produce naturally. Tube amplifiers don't generate the even harmonics, so they have no need for the negative feedback.
The early 70's Marketing pushed the THD (Total Harmonic Distortion) measurment as a indication of superior design of the trasistor amplifiers. A good tube amp may have as much as 5% THD compared to a 0.001% transistor amp, but any true audiophile would rather the tube.
Of course, if all you listen to is rock, the distortion is already in the recording, and you probably won't be able to tell the difference other than the transistor will be able to produce more Watts/$. I had to have this pointed out to me while working at a Hi-Fi shop (all I listened to was rock at the time)
It will just sound like an aural pool of mud.
Seems that you didn't RTFA. This was built by a company who does sound engineering, and is their own showcase system. For some reason, I think that they probably have a better handle on what will sound good or not than you could get from looking at some pictures of their design.
Further, the "attack" you mention that it won't produce for bass drums and explosions, are high-frequency components of those sounds, which are handled by the other speakers. TFA doesn't say this is the only speaker in the system, and TFPictures show what else is in use. The highs get handled by those, the lows get handled by this.
This has been done before- The "New York Experience" Theatre in New York City had a 26 foot horn Sub-woofer built beneath the floor of the audience.
It no longer exists, but was on 5th avenue in the basement of the office building for a book publisher. In the 70's I was given a tour by the operators. The theatre was housed in space that had been built to be used as a small planetarium, but had not been completed. A seating floor was built at the base of the dome, and the speaker was built in the space below. The show was a multi-screen multi-media production giving a virtual tour of NY, with physical props included.
The speaker was an exponential horn, 26 foot in length, and used twice during the show (once was during a subway station scene, I forget the other). The cones of the drivers would only last for about 4 hours of operation, so would have to be reconed every few so many shows. The was built of wood, and curved so that the opening pointed up towards the feet of the attendees.
Having attended the show many times, (early geek destination in NY), I can attest that it was an intense experience, sitting in the opening of such a speaker.
It's a horn. A horn is an acoustic transformer, which matches the impedence of the cone to the impedence of the air, giving a very effecient energy transfer. That means very, very fast bass, with more attack than any brute force method you describe. Your speakers are the equivalent of hitting a feather (the light air) with a golf club (heavy cone). The feather won't go far as there's a big impedence mis-match. The horn gradually makes the air the cone is trying to move match with the weight of the cone, so to speak, like replacing the feather with a golf ball in the above analogy. When the cone moves the air now, it moves easily because of the matched impedence.
To give you an example, my small horn speakers with a 7.5 watt amp go as loud as my brother's PA speakers on his 750watt amp. Do the logarithms and that means that my speakers are 20db more sensitive than his - because of the horns! (actually about 6db of that is due to bigger magnets, but the rest of the increase is down to the horns)
So, the end result is many, many times superiour, with louder sound, with less distortion than your "box" speakers.
-- oldthinkers unbellyfeel ingsoc
It's horn loaded. Ever heard a trumpet or a tuba?
folks like me walk in and say that I can't hear anything different from my $30 walkman.
First plenty of people have explained here that hes only using 6Watts of power to do this. Your puny JL's will not do this. (These guys are using JBL style drivers...look at the cones you can tell :) ) These are not car type devices which tend to be very low efficiency. These are PRO SOUND drivers (not to be confused with the aftermarket car guys claiming they are PRO Sound. The term refers to Professional Sound Reinforcement ie Concert type speakers. JL does not do this nor does any car sub company.) These drivers are close to 100dB/1w1m sensativitey not 85dB/1w1m. Also they are most likely 16 ohm drivers giving him a 4 ohm load to his amp. Beyond all of these differences the major difference is that he has distortion in the UNMEASUREABLE RANGE.....where as IIASCA pretty much is just measureing distortion. IIASCA may make a lot of money playing to the booming kiddies out there but as far as serious acoustics and sound quality they are a friggin joke.
If you cant tell this thing must sound incredible. It has some very serious acoustics behind it and the designer has chosen to not compromise on the setup. I bet it can make your skin crawl :)
I have experienced 4 18" Pro subs in a horn loaded design (Klipsch did this a few years ago at CES). It was fantastic. They used 3 watts of power to drive the subs :)
Braggin about how many watts you speakers take is sorta like bragging about how much gas you car burns per mile. Less is more....not the other way round.
. I love the sound of burning women and screaming rubber....
and you wern't limited to sake, either 8)
It takes 40+ muscles to frown, but only four to extend your arm and bitchslap the motherfucker
Horn don't result in "faster bass". That's an absurd concept, as frequencies only "travel" as fast as they need to. Transients include high frequency components that aren't handled by the subwoofer. The original poster didn't know what he was talking about but you didn't do any better.
Horns do indeed provide great efficiency benefits as well as vastly improved harmonic distortion, but overall they do not exhibit less distortion that "box" speakers. Horns have terrible directivity issues and have very poor frequency response. In this much more important measure of distortion horns don't measure up. For high volume applications horns are desirable and are commonly used, but for near field listening they blow.
Let's break out the mandolin. I don't think the mandolin is the best thing to test out the bass with. Maybe if they were building a giant tweeter.
'Same speed C but faster'
I'm sorry to contradict you but the attack of a sound has nothing to do with frequency, at all.
Likewise, I am loath to contradict you, but I believe you don't quite have it right either.
Sound, as reproduced by speakers in this example, can be described as a combination of amplitudes of varying frequencies. If you put the sound through a Fast Fourier Transform, you can visually see the different frequencies which make up what you think of as the sound. A 20 Hz sound is going to have a slope which is, by definition, constrained by the shape of a 20-Hz sine wave. If the attack of the sound is faster than the slope of that line, that difference is made up by another sine wave (or waves) of higher frequencies, the sum of which add up to the resultant sine wave. A FFT ('an fft?') will show the components of the sound graphically, here is one example. If you took an FFT of, say, a cannon blast, you'd see the low frequency component you expect, but the initial attack would show up as a higher frequency component which is, in this case, handled by the non-subwoofer speakers.
In other words, to get the A of the ADSR to the slope necessary, higher frequencies have to be added to the low frequency to get there. A fast attack, by definition, has to come from higher frequency sounds; it's the only way to get the sum from one place to another quickly.
I think their wrong, but at this level, it's all about taste (or lack of).
I wouldn't say that any true audiophile would rather have the tube. I've heard a one or two good tube amps in my day along with a few bad ones, but nothing touches my Levinsons. I'm certain there is other good equipment but I'm also certain that solid state is competitive with tubes.
It also doesn't matter what you listen to. Absolute fidelity should be the goal every step of the way and my experience is that "audiophile" equipment frequently fails to measure up to that ideal. This is especially true of equipment that needs certain musical forms to "appreciate" it.
Marty, you might not want to hook up to the amplifier. There's a slight possibility of overload.
Purity. Negative feedback is never quite phase coherent with initial signal, you get filtering effects and so on. AFAIR, Bob Carver's wonderful Phase Linear power ampflifiers ran on a similar principal - they sounded terrific, which is why Pink FLoyd's techs chose them as PA power for the Wall tour 25 years ago. We did an A-B test blindfold between these and some MOSFET power amps years ago - and could tell the difference in a matter of seconds. The Phasies won hands down, of course.
Yep, that's correct. I worked with a professional DAT player that went all the way down to DC. Of course not all DAT players will do this, and many people would consider it a flaw (since, for music, a DC offset doesn't produce any sound, but will make the A/D clip at a much lower volume).
We used it to record serial data, either as analog from the satellite, or digital after we'd sampled it, and both worked. Of course, to record RS232, we needed to keep the level in check, but the output looked square on an oscilliscope.
HIV Crosses Species Barrier... into Muppets
"Royal Device has on its own developped and built the biggest subwoofer of the world... SUBWOOFER horns are built underneath the floor in a cavity of 1 meter deep. Each horn is driven by 8 x 18" (47 cm) woofers. "
18"? That's a pretty common size, nothing special there.
Only thing this guy did different was dig a pit and put them in there, making a giant enclosure for the subwoofers.
A subwoofer is defined as a "A subwoofer is a loudspeaker device which reproduces sub-bass frequencies below about 80-100 Hertz" and a loudspeaker is defined as a "a fibrous semi-rigid cone and attached to the apex of the cone is a coil of fine wire (usually copper), called the voice coil or moving coil." So according to the definition of "subwoofer" all he has is 18" subs, not the "biggest subwoofer of the world" by far.
What he has is the largest enclosure, and I'm not even sure if that's right because there are many theaters and amphitheaters designed from the ground up to amplify and direct the sound of bass frequencies which is really all that his enclosure does.
They guy also claims to have the "the biggest AUDIO ROOM for private music listening of the world", but at 6.95 x 8.70 meters (22.8 x 28.5 feet, ~650 sq ft) I have my doubts about that claim too, especially since it has a lcd projector in there so it would have to compete with all those privately owned theaters. I've read that Bill Gate's house has a 1,500 sq ft theater, triple the size of this guy's "the biggest AUDIO ROOM for private music listening of the world".
my karma will be here long after I'm gone
(the 70's was fraught with disaster movies..)
:( There must have been $1,000 worth of hardwood plywood in those boxes...
and the theaters installed super huge sub-woofers for the effect. When the quake hit, they lit off the sub-woofers with sub-sonics that literally made you shit your pants in terror, not expecting it of course, and no one had ever experianced sub sonics like that before. It was awesome. The speakers were trucked from theater to theater in a semi along with the reels.
A few years ago, one of the local theaters folded and they tore it down. They still had a set of the "Earthquake" speakers there and they THREW THEM OUT. I would have picked them up and brought them home but I didn't have a truck at the time
Damn...