Surround sound on the top

[Hoerninger]

The Technische Universität Berlin (http://www.tu-berlin.de/) will offer an ear candy on tuesday, 29th august, in Hörsaal H 104 (http://www.pressestelle.tu-berlin.de/medieninformationen/2007/juni_nr_127-155/medieninformation_nr_129b2007/parameter/maxhilfe/) at 19:30.

There will be a life broadcast of an organ concert transmitted from the Kölner Dom (http://www.koelner-dom.de/index.php?id=2&L=1) to the TU Berlin.

The audience (650 seats) will hear a holographic reproduction from about 2700 speakers (yes, two thousand ..) which are on a band around the listeners in ear height with some extra speakers in the front and at the ceiling.

The applied technique is the wave field synthesis (http://en.wikipedia.org/wiki/Wave_field_synthesis) (WFS) which performes a synthesis of wave fronts out of loudspeaker arrays. The localization of virtual sources in WFS does not depend on or change with the listener's position. The speakers will be fed by digital lines from 832 independent sources, which are generated in a cluster consisting of 16 computers. The transmission from Köln to Berlin is provided by a broadband internet connection.

The organizer announced that this technique offers not only an authentic reproduction of the Kölner Doms acoustics but also the real perception of depth for the different organs within the Kölner Dom.

http://www.koelner-dom.de/typo3temp/pics/6747900734.jpg (http://www.koelner-dom.de/typo3temp/pics/3b91f7dad0.jpg) http://www.heise.de/bilder/113107/0/0 (http://www.heise.de/bilder/113107/0/1)
(click the pictures)
____________
Peter

[Bob Womack]

The Technische Universität Berlin (http://www.tu-berlin.de/) will offer an ear candy on tuesday, 29th august, in Hörsaal H 104 (http://www.pressestelle.tu-berlin.de/medieninformationen/2007/juni_nr_127-155/medieninformation_nr_129b2007/parameter/maxhilfe/) at 19:30.

There will be a life broadcast of an organ concert transmitted from the Kölner Dom (http://www.koelner-dom.de/index.php?id=2&L=1) to the TU Berlin.

The audience (650 seats) will hear a holographic reproduction from about 2700 speakers (yes, two thousand ..) which are on a band around the listeners in ear height with some extra speakers in the front and at the ceiling.

The applied technique is the wave field synthesis (http://en.wikipedia.org/wiki/Wave_field_synthesis) (WFS) which performes a synthesis of wave fronts out of loudspeaker arrays. The localization of virtual sources in WFS does not depend on or change with the listener's position. The speakers will be fed by digital lines from 832 independent sources, which are generated in a cluster consisting of 16 computers. The transmission from Köln to Berlin is provided by a broadband internet connection.

The organizer announced that this technique offers not only an authentic reproduction of the Kölner Doms acoustics but also the real perception of depth for the different organs within the Kölner Dom.

http://www.koelner-dom.de/typo3temp/pics/6747900734.jpg (http://www.koelner-dom.de/typo3temp/pics/3b91f7dad0.jpg) http://www.heise.de/bilder/113107/0/0 (http://www.heise.de/bilder/113107/0/1)
(click the pictures)
____________
PeterYeah, but how many spouses will allow THAT array in the living room? :D

Bob

[Andyoz]

Interesting,

I found this link which explains it well with videos. :)

http://www.syntheticwave.de/3D%20Wave-Field-Synthesis.htm

[syntheticwave]

Interesting,

I found this link which explains it well with videos. :)

http://www.syntheticwave.de/3D%20Wave-Field-Synthesis.htm

Hi Andyoz,

thanks for linking, its my website. Sorry for the bad english, we old east germans has only education in russian.:)

If any questions regarding the principle please post it.


Greetings from Germany

Helmut

[Hoerninger]

University of California at Santa Barbara, the AlloSphere

http://www.allosphere.ucsb.edu/ :
The AlloSphere is a unique, one-of-a-kind research instrument that can be described as a large, dynamically varying digital microscope connected to a super computer to examine N-dimensional data sets and mathematical equations. ...

The AlloSphere space consists of a 3-story cube that is treated with extensive sound absorption material making it one of the largest anechoic chambers in the world. Standing inside this chamber are two 5-meter-radius hemispheres constructed of perforated aluminum that are designed to be optically opaque and acoustically transparent.

http://www.allosphere.ucsb.edu/facilities.php?lab=sphere :
The loudspeaker real-time sound synthesis cluster (around 500 individual speaker elements plus sub-woofers) is/will be suspended behind the aluminum screen resulting in 3-D audio.

http://www.independent.com/news/2008/nov/06/enter-allosphere/ :
...three stories high, 2,000 square feet, engineered by sonic wizards to be acoustically neutral, making the sound in this round chamber equally good at any wavelength, anechoic. Right now, 16 four-inch speakers surround us, though eventually there will be 512. The sphere has two curved screens, suspended like floating mists in the semi-gloom. Only one side is currently operational, but soon spectators will be completely bombarded by sounds and sights of physical phenomena projected front and rear via supercomputer.

http://www.create.ucsb.edu/%7Estp/AlloSphereAudioSlides.pdf (page 8), see below.

A bit more than 5.1 ;) , Ambisonics as well :thmbsup: .
____________
Peter

[syntheticwave]

...but if we include the reflective surfaces of the playback room in synthesis, only 1296 loudspeakers remain for 3d WFS. See
http://www.holophony.net/WFS-Holophony.htm

[JBL 4645]

http://www.heise.de/bilder/113107/0/1


I’m wondering thou its more or less the same set-up arrangement as a regular cinema only six times as many lined along the sidewalls.

I never sat close to the sidewalls to watch a film from start to end. I might have only sat near to the wall in the upper stalls at the Empire around February 14th 1992 but then I was watching the same film 3 times and only once tried the side and was still able to hear the surrounds envelopment from Star Trek VI from inside the bird of prey.

I wonder how many of you would fight to get a centre line seat in cinema? Front and centre is good for total wild wide stereo front. The further you move back the sound gets lesser and less in db and that’s a fact as well as stereo becomes narrower and that too is a fact.

First row moving back to middle row stalls or circle is okay for fronts and surrounds.

Also I don’t like the circle in this cinema its got a stairway right in the middle and I don’t like cinemas with great hole in the middle so I wont sit anyway in the circle. Front stalls yes.

Another is cost and how well it would be to maintain the surrounds for spare parts over the years. I hope they the edge rubber surrounds for long durable reliability use.

[syntheticwave]

The further you move back the sound gets lesser and less in db and that’s a fact as well as stereo becomes narrower and that too is a fact.
...but with the loudspeaker rows not in the same degree. While point source decline at 6 dB for double distance, the cylinder waves of the loudspeaker rows only lose 3 dB. At the "acoustic curtain" from the Holophony approach, in theory the sound pressure remain constant at increasingly distance, actually.



Another is cost and how well it would be to maintain the surrounds for spare parts over the years. I hope they the edge rubber surrounds for long durable reliability use.
..the loudspeakers in the acoustic curtain needs no edge rubber. Because of the perfect air resistance adaption (http://www.syntheticwave.de/Speaker_Field_Adaption_for_WFS.htm) in the loudspeaker field, the diaphragm needs hardly excursion.

H.