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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 horn is an acoustic transformer that links the cone to the air in the room very effectively. For good results, a bass horn has to be very large, on the scale of the wavelength of the notes it's reproducing.
The bass you hear on your home hi-fi is most likely produced by resonance, something you should avoid if you really want to hear what those bass notes are sounding like. But resonance is cheap! Large bass horns are neither cheap, nor easy, but they sound so much better...
-- oldthinkers unbellyfeel ingsoc
these guys build custom home cinema installations so this was either for a client or I think their own demo to show off what they can do....
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.
this might seem odd to you, but some people design listening systems for sound quality, not volume. if you'll RTFA, you find that the amp is only delivering 6W to each of 2 horns (despite total power handling capacity of 6400 watts).
full-sized church pipe organs are specially tuned. Each pipe plays exactly one note, and the pipe's length determines the wave length. The high ceilings in a church also help.
Why read the article when I can just make up a snap judgement?
FYI, Church organs go to 32 foot pipes. The good ones go one rank further to 64 feet. These are the big folded pipes in back. You won't get to see these unless they have a viewing window to the real pipes. They are not the pretty pipes in front. The 64 footers are almost always folded double or triple (like most brass insturments) because the pipe loft isn't that tall. Due to the shape of the pipe, it's throat, and other attributes, most pipes don't play exactly one pitch. That's why they don't all sound like sine waves or have a flute sound. Some pipes have brass and trumpet sounds instead of flute sounds. This is due to the harmonics generated by many pipes to give them rich fat sounds by design.
The truth shall set you free!
32 foot pipes are the largest commonly found, and even then only on very large instruemts. A 64' pitched rank is exceedingly rare. The only instrument I'm aware of (in the US) with real 64' pipes is the one at the Atlantic City Convention Hall (website: http://www.acchos.org/ ).
The Washington National Cathedral, in DC, has a 64' pitched rank, but if I recall correctly it's electronic (using speakers), not with actual 64' long lengths of pipe.
Bear in mind, a 32' pitch C is already below 20Hz, well below what most people can hear. A 64' pitch is more of an impressive "special effect" than anything else.
Actually, if anyone else can cite another pipe organ with a 64' pitch (US or otherwise), I'd love to hear about it, so I could hear that monster!
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Much like a newborn puppy...