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Linux PCs Drive 74-Channel Pipe Organ
cyberman11 writes "According to the EE Times, Marshall & Ogletree LLC have created an electronic simulation of a classic Aeolian-Skinner pipe organ in the Trinity Church situated, just 600 feet from ground zero near the World Trade Center site in New York. The system consists of 10 Linux PCs that drive 74 Carver amplifiers and 74 Definitive Technology speakers, for a total of 15,000 watts."
...don't have amplifiers or computers but usually do have >100 pipes.
So this is a modern pipe organ?
Hate to point out the obvious, but without pipes it's not a pipe organ. In organ circles, these are known as "electronic" organs (crazy jargon, I know).
Looks like an interesting project though. Electronic organs have never sounded remotely as good as the real thing (and they've been making them since the 60s at least). For all the thought and work they've put into this, I wonder if it will sound significantly better.
PC-enabled tones rise from ruins of 9/11
By Ron Wilson
EE Times
December 3, 2003 (4:30 p.m. ET)
SAN MATEO, Calif. -- As the towers of the World Trade Center crumbled on that September day two years ago, the plume of debris they spewed claimed a victim that, although not human, was nonetheless irreplaceable to those who loved it: the mighty pipe organ in Trinity Episcopal Church at Broadway and Wall Street. Dust and detritus from the collapse rendered the church's 80-year-old Aeolian-Skinner organ unusable.
But that lesser tragedy opened the door to a unique story -- of musical skill, love of an instrument, insight into signal processing and innovation in electronic systems design -- that this year has brought about a resurrection of sorts. Today a new mighty organ plays at Trinity -- not a pipe organ, but perhaps the most innovative electronic instrument ever to fill a sacred space.
For Douglas Marshall and David Ogletree, principals of the Marshall & Ogletree LLC organ company in Needham Heights, Mass.), the loss at Trinity Church would transform what had been a hobby, perhaps an obsession, into a product development. It would be a unique chance to prove that the contrarian ideas they had formed over the course of a decade were correct, and that conventional wisdom about sampled-data electronic instruments was at best incomplete.
Vanished gloryThe story began long before terrorists boarded airplanes that late-summer morning in 2001. Marshall and Ogletree, who grew up 15 years apart in Westwood, Mass., and who both went on to careers as concert organists, in the early 1990s formed a company to represent major organ builders to the church market.
Along the way the two developed a love of the great Aeolian-Skinner pipe organs that are arguably the finest organs ever built in North America. With the Aeolian-Skinner Organ Co. gone, Marshall and Ogletree speculated about how the sounds -- and, more important, the playing experience -- of such instruments could be preserved.
They hit upon a project to record samples of existing instruments around the United States and experiment with them. "We had hoped that we could build some sort of addition to an electronic organ that would convey the real sound of these instruments," Ogletree explained.
The theory of sampling musical instruments is relatively straightforward. Depending on its physics, an instrument has an attack, a steady-state and a release, each of which has a different tonal signature. This complexity can be reduced substantially by a few approximations -- for instance, using the steady-state tone and simply modifying it with attack and release envelopes, perhaps throwing in some transients known to occur at the opening and closing of the "voice."
In this sort of approach, it's only necessary to get a good recording of a moment of the instrument's steady-state voice, and the rest is signal processing.
But Marshall and Ogletree ran into a problem: That approach didn't end up sounding like the real thing. "In 1997 or so, we were doing experiments with the digital sampling software that was just coming on the market," Ogletree said. "They were just starting to stream high-fidelity recording onto hard disks, and we were playing with it. We began to realize that the length of the recording made far more difference than we had believed."
It had been assumed, Ogletree explained, that the sonic content of an organ voice matched what most people reported hearing. There is an initial, transient period of a second or so, after which the human ear can identify a particular note and stop, and then the voice remains constant until the release.
But the data Marshall and Ogletree were collecting contradicted that. "The tone actually become steady a very long time after it seems to have settled," Ogletree said. "Recorded samples of the attack have to be as long as 15 to 20 seconds to capture the actual voice, because there are things going on during that entire period -- it's not a
litigious bastards
suck it sco!
If you've seen a large pipe organ they can consist of thousands of pipes spread over a rather large area. The acoustic effect of having different tones coming from totally different areas of an auditorium is completely different than placing a hundred speakers throughout and having every one of them replicating the same sound.
There's more to it than that...but that's all I feel qualified to bring up.
check out http://www.hauptwerk.co.uk/ some of the larger organs (sampled pipe-by-pipe) require up to 1.5GB of ram to work and sound really good (check the site for samples esp. the ones of the commercial organ vendors).
-- the cake is a lie
1% is if you're lucky
the new sony dream system and the new panasonic system both have 10% of THD. but they're 600watts tho so people will still buy them.
THD, along with wattage are still only small factors in the sound a speaker puts out. materials used to make the cone, sensitivity, and resistance influence the sound enough so that your ear can actually tell the difference.
This is pretty much why bose doesn't publish the specs for their speakers. they have great marketing, but their speakers are CRAP. Most bose speakers have an eq in that completely elimanates all the sound that the speakers just can't take....bose still uses paper cone speakers and foam in their "bass modules" (they ain't subwoofers, they're only 5 & 1/4in speakers, subwoofers start at 8in). The foam dry rots after a few years and you're left with a crappy set of overpriced speakers that throw away most of the sound.
Actually, it was coined by the New York Times. The guy who wrote the article about the Nagasaki bombing back in '46 added "ground" to the "zero" that they put at the middle of the maps they handed out to the reporters about the projected damage to make it sound like he was all "embedded" and shit. Talking about lighting-filled clouds rising thousands of feet above "zero" sounds kinda stupid, though, so he changed it to "Ground Zero" to make it sound more dramatic and jargon-y.
You also have to take into account that certain stops cover certain frequencies. Therefore your Piccolo on the Upper is not going to be coming out of the same speaker as the Tuba on the Swell, it would sound terrible.
I'd also wager that some channels are specifically for bass. Organs put out a lot of bass - most of it will also be felt rather than heard. That also goes some way to reproducing an organ sound live.
Ultimately, live sound is a totally different kettle of fish from recorded sound. That's why Britney doesn't sound like she's in your room when you turn it up loud, and also why The Rolling Stones don't tour with 2 speakers...
I'm noticing a fair amount of discussion here regarding "...why 74 amps/speakers?" As someone who has worked on pipe organs, here's what I am assuming:
- They have one for each stop (or subset of stops) on the original organ.
What is this "stop" I refer to? It's a collection of pipes with a specific sound... Vox Humana, Trumpet, etc., that the organist can choose and (in some cases) assign to a specific keyboard. An organ the size of the Trinity Church Aeolian-Skinner would have had dozens of stops. Even a small pipe organ has quite a few -- more than 10 is quite common.Each stop has a default keyboard with a specific name, related to which wind chest the pipes are located on ("Great", "Swell", "Choir"... though those are just starting points).
Along with the location of these pipes on certain wind chests comes other factors... only the set of pipes on a chest called 'swell' can have their volume controlled -- usually by way of a set of shutters that open and close. The rest of the organ pipes play at the same volume all. the. time.
Another thing about pipe organs... some of them (I don't know about this specific one) run on very high pressure. Normal for the pipe organs I worked on was 8 to 10 inches of water. I heard one that ran at 80 inches of water, and the 'attack' of the sound was like a gunshot. I have yet to hear a speaker that can duplicate that sound.
"...America's great minds of today, teaching America's great minds of tomorrow. Poor bastards." -- A Beautiful Min
Anyone who browses Slashdot with his/her family around should know better.
Use ISO 8601 dates [YYYY-MM-DD]
I like pipe organs; Bach on a big pipe organ is awesome. (Re-reading that sentence it occoured to me that's probably the only time I properly used the now-trivialized word "awesome".) But lets move on ...
...), the worshippers need to invite him into the fold to get that End Of The World thing going.
I'm not much of a church goer, but whenever I'm in a new city I try to find out if there are any good pipe organs in town (a big city might have none, one, or a couple) and I will spend a Sunday morning in church.
They all sound different, and the church itself is as much a part of the sound as anything. Pipe organs in general have lots of power, the kind you feel as much as you hear.
I've spend most of my life in Audio, and I can tell you without any reservation at all that I've never heard a pipe organ properly reproduced on any sound system, period. Cannons? Yep.
Full Orchestras? No problem.
Rock n Roll? I've sworn I could reach out and touch musicians.
Pipe Organ? I've heard it come close, but you always know.
So, these guys can't be faulted for lack of ambition.
A difficult concept to pull off; I would love to hear this attempt, which pretty much mandates that I go back and listen to the new organ when they rebuild it. My guess is the real deal will sound subtly better. It's a given that they will sound different, even though recreating a live insturment in the same room is less challenging than recreating something with a recording. But, since I've heard neither, that's just thinking out loud.
I was a bit suprised to learn they chose DT speakers because the wanted a bipolar; they make good gear but there are other bipolars I would have considered (maggies, for one; I've done church installs with them and they work very well in the typical acoustic space a church provides).
Having said that, I would have tried omnipolar speakers first; in my way of thinking they would have a better chance to reproduce the acoustic signature of pipes (omnipolar radiate 360 degrees, like an organ pipe does; bipolars radiate front + back but little to the sides).
The Carver amps were also a bit of a suprise; I've never found them to be top-notch although they're certainly better than average.
Of course, it all makes sense if go a bit crazy here and assume they were radical enough to have bought into some wild concept I've heard about called "A Budget".
I agree that Linux is the proper OS. If Bill IS the Antichrist (not to say he is, but
Better safe than sorry, I say.
Deutche Grammophon did an album by Bach that was recorded on the world's biggest pipe organ - Organ of the Jaegersborg Church, Copenhagen. The album, Famous Bach Organ Works from Karl Richter, is fantastic at tearing apart speakers :) The album, is available on CD now but mine is on an LP. If you have a great stereo, this will get you close to what a true pipe organ sounds like.
Banjo - The more I know about Windoze, the more I love *nix
I've heard it :) It's clearly unlike any other electronic organ. While it's not exactly the same as a real pipe organ, it comes remarkably close to the experience. The pipe sounds do in fact act like the real thing. If you have a chance to be in NYC it's definitely worth checking out.
k s like they mostly have links to other
Btw, I found the builder's site: http://www.organpower.com/html/m_o_home.html
Loo
news stories at this point.
The more wattage you feed into a given system, the louder it will play, until you reach teh speaker limits. If I feed 1 watt into each of my speakers, I get a nice normal listening level. If I feed 150 watts into each speaker (the limit of my amp) I'd blow my eardrums in short order.
Now, there are other factors that matter in loudness. The next one after wattage would be efficency. Given a watt of input, what kind of output does a speaker give? Obviously, the more efficient the speaker, the louder a system will be at a given wattage. I don't know how efficient most consumer speakers are, they don't usually list the stats. Good high end speakers (pro/audiophile) tend to be in the 88-90dB/watt @ 1 metre. A stage speaker can be in the 100-109dB range, maybe even higher though I've never heard of one.
Well then the @ 1 metre spec brings us to another component: distance of the listener. Loudness depends on proximity to the source of the sound. Thus a person sitting next to a speaker will hear a much different level than one across the room.
The room, yeat another problem. In an environment with no reflections, sound will decay much faster than an environment with lots of them. So depending on the kind of hall you are in. In a very dead hall, people in the back will hear much less sound in the front. In a properly designed hall, they'll still hear plenty.
Of course it doesn't end here, it depends on lots of other things like frequency range, which drivers are being used how much and so on.
Point is there are too many vairables to try and give a final number as to how loud something will be. None the less it IS desirable to have SOME kind of indication. Well wattage is a good one. Not a great one, not a final and all consuming one, but a good one. If I have a 1000 watt system, I can say with some confidence it is going to be pretty loud. IF I have a 10 watt system I can say with some confidence it will not be nearly as loud. I can't caluclate an absolute difference, but I can get a general feel, with one number. If you want a better loudness stat, the best you can reasonably do is a wattage stat and a sensitivity stat. Past that, it all comes down to specifically what you are using it for.
As a side note, 1% THD is quite acceptable for speakers, and you'd not notice it unless you knew what to listen for, and even then probably only on a sinewave test. My high end speakers (cost over $2000/pair) produce 1%THD (or even more) at high volume levels.
Which, of course, is another consideration, since you're being pickey about stats. THD at what volume level? Speakers' THD increases with volume. Also within what frequency range? A speak setup may have good THD over most of its range, but under or over a certian point it may increase quite a bit.
Stats aren't perfect. Deal with it.
good amps, and good speakers, there's no doubt that the efficency of the system is going to be very high,
In tweak gear--esp. speakers--efficency is lower. This is due to optimizations to gain linearity. Practical electro-magnetic systems are dreadfully nonlinear; to flatten the curves, power is wasted. what it is.