wave field synthesis approach - Discussion

[helmut oellers]

Caruso was a mono sound source without all doubt. Therefore seems
sufficient the transfer of the assigned pure audio information in a
single mono channel. The spatial sound field becomes created in the
Milan Scala only by the fact that a large number of spatial dispersed
mirror sound sources occur. According her room positions arise signal
delays regarding the listener and the reflection factors by the
surfaces influencing the frequency response and level of these mirror
sound sources. Though the signal itself always is Caruso's mono
source.
The conventional methods are now seeking to reduce the spatial
distribution of those sound sources upon few audio channels by
psychoacoustic principles. This always caused a loss of spatial
information. Much more effective seems the synthesis by the rendition
side, by which in principle all sound sources in their correct
position can be mapped.
This " Wave Field Synthesis" approach is known since two decades,
depicted by

http://en.wikipedia.org/wiki/Wave_field_synthesis.

Let´s discus the advantages and disandvantages of this approach.

Regards Helmut
www.syntheticwave.de

[Clyde Slick]

On 9 Dec, 08:14, helmut oellers > wrote:



disandvantages of this approach.


$$$$$$$$$$$$$$$$$$$$$$$

and some of us actually have to live in our houses.

[helmut oellers]

On 9 Dez., 15:28, Clyde Slick > wrote:
> On 9 Dec, 08:14, helmut oellers > wrote:
>
> disandvantages of this approach.
>
> $$$$$$$$$$$$$$$$$$$$$$$


........yes, that's one of the formidable advantages of the procedure.
No investor would pay in a solution, if you can purchase the product
for a few bucks. You cannot achieve good commission by such
approaches.
The marked increasingly share into polarised groups worldwide yet, the
transistor radio users and the high end users. Early adapters would
surely pay $ 100.000 for a solution, if its reproduction hardly to
distinguish from the genuine sound field.
Later seems possibly a 2000 $ solution for mass production, because
the repeating structure of the elements fits perfect the automatic
production requirements.

H.

[helmut oellers]

> Nonsense:http://youtube.com/watch?v=8m8fbnShPcw, and you can use used
> paper plates. Start saving now.

:) Hi Bob,

I would not connect such speaker by my amplifier, but what you
describe is correct. Because of the amount of speakers for wfs the
membrane elevation of each remains very low. That decreases the cost
dramatically.

H.

[Clyde Slick]

On 9 Dec, 12:14, "Soundhaspriority" > wrote:
> "Clyde Slick" > wrote in message
>
> ...
>
> > On 9 Dec, 08:14, helmut oellers > wrote:
>
> > disandvantages of this approach.
>
> > $$$$$$$$$$$$$$$$$$$$$$$
>
> Nonsense:http://youtube.com/watch?v=8m8fbnShPcw, and you can use used
> paper plates. Start saving now.
>
>
>
> > and some of us actually have to live in our houses.
>
> They glue to the wall. You can still walk around.
>

Contrary to what Arny says, you need to use a better quality paper
plate and thicker gauge aluminum foils.
However, I would not recommend swapping out the penny for
a quarter. How many ohms is that speaker?

[helmut oellers]

> Yes, Helmut. I wonder if the math would allow substituting binary state
> transducers in a very large array? That would simplify greatly.
>
> Regards,
> Bob Morein
> (310) 237-6511


Hello Bob,

I think the common practice of speaker arrays hasn't future for wave
field synthesis in the home area. By my opinion becomes the " acoustic
curtain" approach much more possibilities. Have you shown the www.syntheticwave
site? That describes the advantages of such speaker field.


H.

[helmut oellers]

> May I have the link again? The extension is missing.
>
> Bob Morein
> (310) 237-6511- Zitierten Text ausblenden -
>
> - Zitierten Text anzeigen -

....sorry, i forgot i am a German ...

www.syntheticwave.de

is a animated depiction, easy to understand.


Regards Helmut

[helmut oellers]

On 9 Dez., 23:38, "Soundhaspriority" > wrote:
> "helmut oellers" > wrote in message
>
> ...
>
> >> May I have the link again? The extension is missing.
>
> >> Bob Morein
> >> (310) 237-6511- Zitierten Text ausblenden -
>
> >> - Zitierten Text anzeigen -
>
> > ...sorry, i forgot i am a German ...
>
> >www.syntheticwave.de
>
> > is a animated depiction, easy to understand.
>
> > Regards Helmut
>
> Yes, I understand. But I do not understand your differentiation between an
> array, and the operating principle of wavefield synthesis.
>
> The website animation depicts the reconstruction of a wavefront by Huygens
> virtual emitters. The Huygens concept is a visualization aid. In practice,
> the Huygens virtual emitters must be replaced by real emitters; hence, an
> array.
>
> Bob Morein
> (310) 237-6511

Hi Bob,

translation problems possibly, usually in connection to wave field
synthesis the word array describe the speaker rows, not a field. But I
know a array may also have two dimensions.

Of course must be the emitters real speakers, but you can use used
paper plates.


H.

[helmut oellers]

On 10 Dez., 01:14, "Soundhaspriority" > wrote:
> http://www.ece.cmu.edu/research/publications/2002/CMU-ECE-2002-001.pdf

...Super! That fits exactly what would be need for the perfect
rendition. Forgot aliasing, you can restore the soundfield genuine
like by a sufficicient amount of such speakers. I think it would be
possible to combine that by LEDs for picture screen!

Pow! Helmut

[helmut oellers]

> 2. The data is reduced according to wavelength (for lower frequencies, a
> larger block of elements can receive the same pulse than at high
> frequencies.)

That's the Idea of http://www.1limited.com/ Anthony Hooleys sound
projector and http://iem.at//index_html_en IEM Gratz works on the
topic. According to theory a constant directional characteristic,
during local continuous source distribution, adjusts itself if in each
spatial window finds place the same number of wavelengths.

But is the window sufficient large, possibly 3 meters diagonal, the
directive effects occur under frequencies of app. 150 Hz, no cues for
spatial perception.


H.

[helmut oellers]

On 10 Dez., 01:13, "Soundhaspriority" > wrote:
> Helmut, see this:http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel5/7726/21214/0098...
>
> Somewhere, I've seen a whole article. *Perhaps this would make the synthesis
> practical:
>
> 1. A two-dimensional array of binary elements.
> 2. The data is reduced according to wavelength (for lower frequencies, a
> larger block of elements can receive the same pulse than at high
> frequencies.)
>
> Bob Morein***************(310)*237-6511*******

Hi Bob,

by the last days I improved the animation for the transformation
principle. Think is quite easy to understand now:

http://www.syntheticwave.de/sound%20field%20transformation.htm

Anybody know another ways to restore the spatial soundfield entirely?


H.