Holophonics

[syntheticwave]

Hi,

anyone knows this principle?

http://www.holophony.net/

shoud it work better as surround?

regards H.

[russ.will]

I believe this technology was first shown by 1Ltd for circa £10k and has since trickled down to the Yamaha YSP Sound bars currently available for as little as £300.

The whole point of it is that you don't have surrounds - it directs the acoustic wavefront to bounce off a wall where the surround would normally be. That's the theory anyway.

Russell

[syntheticwave]

Originally Posted by russ.will

I believe this technology was first shown by 1Ltd for circa £10k and has since trickled down to the Yamaha YSP Sound bars currently available for as little as £300.

The whole point of it is that you don't have surrounds - it directs the acoustic wavefront to bounce off a wall where the surround would normally be. That's the theory anyway.

Russell

Hi Russell,

no, by my view it’s a huge difference regarding the sound projector technology. Yamahas YSP`s build virtually loudspeakers by the principle. That remains phantom source based, real spatial depiction isn’t possible. But the described holophony approach restores the sound source itself as a virtual source, not depend by the phantom source perception.

H.

[Mark.Yudkin]

Isn't the underyling "Wave Field Synthesis" a generalization of the virtual point source used on all Quad ESL's (such as my ESL-63's) since 1981? See page 8 of http://www.quad-hifi.co.uk/downloads/ESLBrochurelow.pdf.

One difference is the use of monopoles (at least within the room) as opposed to the dipolar radation in membrane speakers. Another is that by using multiple (real) point sources outside the room, these can be mixed at the membrane whilst retaining spatial information: hence the term holophonic. [This is of course a ludicrous over-simplification].

I doubt that the technology would be viable in a domestic environment. Most people can't even get 5.1 surround working properly due to room constraints: it's all about compromise.

[syntheticwave]

Originally Posted by Mark.Yudkin

Isn't the underyling "Wave Field Synthesis" a generalization of the virtual point source used on all Quad ESL's (such as my ESL-63's) since 1981? See page 8 of http://www.quad-hifi.co.uk/downloads/ESLBrochurelow.pdf.

Yes al lot of similarity. Unfortunately there isn’t a English translation for the German “Phantomschallquellen” link in the http://www.holophony.net/ site. It describes the reason, why ELS reproduction often much better as conventionally speakers. The reasons aren’t the better response or so, the reproduction becomes less influence of the playback room because of the directed radiation of the enlarged membranous surface. That’s the most important fact, hardly misguiding cues arise.

But one single ELS only able for produce one single such virtually source. The described Loudspeaker field behind the screen wall is able to produce a huge amount of such virtually sources, distributed on the same positions as in the recording room. That isn’t reproduction in the sense of the known playback procedures, it is a physically restore of the spatial sound field. The holophonics seems me to be the acoustic expression of the holography principle in the picture world. Both principles based by Huygens Principle. http://en.wikipedia.org/wiki/Huygens...snel_principle

[Mark.Yudkin]

To be honest, the English translation on the web site was so bad, I just gave up on it and read the German original.

The section you're refering to makes no mention of the virtual point source, which is far as I know has only been implemented by Quad in membrane speakers. Rather that section is a general discussion of membrane speakers in a near field position, with ESLs as an example. I do of course disagree violently with the claim in the second sentence below:

Weil das Bündelundsmass der Lautsprecher in den Hallradius eingeht, kann mit grossen Membranflächen, wie bei den Elektrostaten, auch unter Wohnzimmerverhältnissen Nahfeldwiedergabe erzielt werden. Das ist die Ursache für ihre Beliebtheit.

The low membrane mass with it resultant minimal inertia (ringing, transient responses), lack of crossover, absence of cabinet colouration, etc. are probably substantially more important than the radiation pattern in producing that quality of sound that I wouldn't want to lose.

I believe I concurred in my first post with the extension to multiple virtual sources as being the major feature.

[syntheticwave]

Yes it’s really better to read the German site, if you have the ability.

The phantom source- site only describes the problems, the solution depicted on the other sites. The animations possibly better as the text, show per example the single virtual acoustic source by the http://www.holophony.net/virtual%20a...c%20source.htm site.

Each point upon your ELS diaphragm may regard according Huygens Principle as such starting point of its own wave front. That generates the directed wave front, besides the other reasons you mentioned one of the most important facts for the perception, also by my opinion.

[syntheticwave]

Originally Posted by Mark.Yudkin

I do of course disagree violently with the claim in the second sentence below

I have seen now a english translation of the site:
http://www.syntheticwave.de/Phantom-sources.htm