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Old 12th April 2012, 04:06 PM   #22171
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In any case, I wish the guy well, and I hope that he sold a few units and made a profit.
That is a major reason for this thread, which is to promote this kind of design approach, similar to what Charles Hansen and I do with our best efforts.
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Old 12th April 2012, 06:29 PM   #22172
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Quote:
Originally Posted by simon7000 View Post
(Note ref, Serbian or Croatian)

Scott, welcome to the "Diss'd" club. I have a French non-fan. But your's does seem quite a bit crazier!
One of my best friends in high school was Serbian, I got some first hand accounts. This thing was unfortunate, in retrospect I used words that were too harsh. Milan is obviously a very intelligent person and very well spoken in English more than I can say of my Serbo-Croatian.
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Old 12th April 2012, 08:57 PM   #22173
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Sy,

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Originally Posted by SY View Post
Why did Constantinople get the works? It's nobody's business but the Turks'.
With respect, the Turks are the aggressive occupiers in Constantinople, which is part of Christian Europe (including the Church of Saint Sophia).

Of course, it all happened so long ago that possession became the law and without the conquest and sack of Constantinople by Mehmet Europe may never had it's renaissance, may never have sucesfully settled the America's (after mostly doing to the natives what Mehmet's armies had done to the inhabitants of Constantinople) and thus industrial revolution and the internet may have never been invented...

Ciao T
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Old 12th April 2012, 09:27 PM   #22174
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Is that all? '-)
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Old 12th April 2012, 10:04 PM   #22175
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Originally Posted by john curl View Post
Is that all? '-)
No,

Entirely off topic and out of rules boundary would be the tale of why there are places that have Popes. But anyone interested can Wiki that,

We could discuss the Vatican sound systems, but not very surprisingly bribery was involved in the design of at least one of the systems I am aware of. (Along with a few respectable threats...)
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Old 12th April 2012, 11:51 PM   #22176
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Interesting spin off the houses of worship international PA systems info. I have seen very elaborate ones in reinforcement industry's brochures, websites. In usually equally elaborate acoustically treated huge spaces with interesting interior blending design. Are there any special acoustics crafted for such installations? Like some differentiated reverberation time bracket of client acceptance or different standards for the cabinets & mic arrays than for music halls? I know they would accept only AKG condensers & column array speakers in most local orthodox churches for instance and would pay one off and in cash if chuffed.
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Old 13th April 2012, 02:46 PM   #22177
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Interesting spin off the houses of worship international PA systems info. I have seen very elaborate ones in reinforcement industry's brochures, websites. In usually equally elaborate acoustically treated huge spaces with interesting interior blending design. Are there any special acoustics crafted for such installations? Like some differentiated reverberation time bracket of client acceptance or different standards for the cabinets & mic arrays than for music halls? I know they would accept only AKG condensers & column array speakers in most local orthodox churches for instance and would pay one off and in cash if chuffed.
At first in the US, RCA was the dominant force in public use sound systems. They built a central amplifier and would wire primarily schools with it and a switch bank. It could be used for a classroom intercom system, a school all page or even to provide sound just in the auditorium.

Altec Lansing started selling equipment to the electrical contractors through a national electrical equipment distributor (Graybar.) This lead to establishing specialty sound contractors. One Altec Vice President (Don Davis) developed a method for designing sound systems and spent enough time doing this that he upset the sound system consultants. So he went off on his own. (Probably not by entirely his choice!)

Well in the US, Don Davis used to give courses in how to design sound systems. He developed a method based on a central cluster system (point source) and lots of rules using scientific calculators and decibels. Basically he assumed that people spoke 2 feet away from a microphone and that the distance from the speaker to the microphone determined how much gain you could get before feedback. He modified this distance by a directivity factor called "Q." He also allowed for a gain reduction by the square root of the number of microphones or speakers in use. You also tossed in a safety factor of 3db. There also was an absolute limit of the maximum speaker to microphone distance due to reverberation. He used the critical distance for this.

When you produce a continuous sound from a source the reverberant field will build up to a steady level. At some point the direct field due to the inverse square law will diminish to that level. That is at the critical distance.

The idea was to place the cluster high and centered, calculate the coverage angles and pick a speaker with a "Q" that would meet the design goals. The design goal was for everyone to have a sound level equal to being 8 feet away from the person talking. He also had a formula for predicting speech recognition. You were supposed to do all of these calculations using decibels. When simplified to divided the length of the room by 8 and make sure the speaker is that far away from the microphones the method seemed to loose a bit of it's magic luster.

He was influential enough that most professional manufacturers listed "Q" values on their data sheets.

However in Europe there were far fewer church sound systems and they were just changing from having folks such as Phillips & Siemens do them to using smaller firms. The smaller firms only knowing the physics and not having been properly "trained" reverted to the older form of loudspeakers designed to project in reverberant fields. So they used sound columns, now called line arrays.

As these caught on worldwide there was controversy from the Davis camp. (I got really nasty letters from them for an article I did on Bruel & Kjaer's Rasti meter that not just said it was useful, but that the assumption of Davis that speaker throw increased by the square root of "Q" was not accurate.)

Around the same time Wolfgang Anhert (E. Germany) had developed a modeling program that was brought to the US by Renkus Heinz. (Some interesting stories there!)

Well since worldwide line arrays and prediction software were adopted sales of pro sound equipment that were basically stagnant have now tripled.

Now interestingly enough very few folks know how to apply sound absorption treatments and it is much easier to sell electronics, so only a few specialist consultants use acoustic treatments. Even when such treatments are done, after ten or twenty years the reason for them is forgotten and they get painted over ruining them. Even worse is the organist who "knows" more reverb is always better gets them removed.

So churches with bad sound systems will just buy new ones every few years hopping for some magical improvement.

Last edited by simon7000; 13th April 2012 at 02:51 PM.
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Old 13th April 2012, 02:57 PM   #22178
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I know of a church in St Paul that has been doing just that. Still can't get it right.
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Old 13th April 2012, 03:15 PM   #22179
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I know of a church in St Paul that has been doing just that. Still can't get it right.
Do they have money?
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Old 13th April 2012, 03:16 PM   #22180
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Interesting input, Ed. I knew Don, and most of the companies you talked about. We are an incestuous bunch! '-)
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