This thread has been separated from the DIY sticky as it is an important discussion to have, but should not be retained within the sticky DIY thread until a satisfactory conclusion has been reached. HR


Corner absorption was patented and expired. I know this history rather well. The patent, who bought the license and how it was commercialized.

The chunks are a very typical extension on the acoustic concept of corner absorption, still hardly understood, by using the edges of the board in function of specific entrance impedance, and whatever yet undescribed effects.

I'm VERY interested in more details, but want more than vague references, but people wittingly applying it in function of the by them known and investigated specific corner absorption behavior. And I do know the original patent. I entered that reference myself on the net in groups.

Hence I want Max arguments detailed here, and references of people describing this behavior in function of chunks.

I know how labs react when they see this behavior for the first time. And that relates already to a Belgian, an Australien and 2 US labs.

And I do mean this question. I realy do.

I'm VERY interested to find more about this history. And I want yo hear Max arguments with exact references to people consiously using it, who studied/understood this behavior.
In the most recent Dr. Peter D'Antonio and Trevor Cox book about absorbers it's still open cell absorption is still described as an inefficient application contradicting acoustic. The Modex system of RPG is based on a typical membrane approach. The Pro-Corners of RPG date most likely from AFTER this text is written.
And I'm sure that Dr. Peter D'Antonio and Trevor Cox have as much access to Studio related literature than Max.

I know that lots of people on the net now act if they knew it all along for ages.

Hence I like details from Max, showing that the corner chunks with there typical design were a known and understood application.

This design are 'Studiotips Super Chunks' or SSCs until shown otherwise.

In the States aren't relatively that many commercial labs.
I recently talked with the Manager of Riverbanks (the only lab founded and designed by Sabine himself and the earliest established in the world in function of architectural acoustics) in Geneva/Illenois/US personally about this.
He confirmed that they only were confronted the last years with this phenomenon.
Another guy discussed this with an Australian Lab, exact the same story.
I know how surpriced the lab here was in function of this behavior, type of measurement they never saw before. I was the first in Belgium who ever measured that in a lab (I don't claim to be the inventer) and that includes 3 different University labs and 1 lab from an official research institute.
When we tried to mathematically explain this behavior, no literature was found describing this, and literature study is standard procedure in an Univ. They have very extensive access to literature via there libraries.

All those pro's even on academic levels in labs are surpriced, but in groups everybody acts as they knew it for ages as the most obvious common knowledge.

I'm still searching for studio groups messages about it predating Studiotips info in function of related research.
I welcome it with OPEN arms, since I'm really interested in the history of this, "so obvious common knowledge".
And I do remember quiet well my first related discussions here with Max about corner absorption, which wasn't that obvious or well known to him in those discussions.

Best regards
Eric

Edited by Hugh Robjohns (11/08/06 09:21 AM)

Quote EGAM:

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In the most recent Dr. Peter D'Antonio and Trevor Cox book about absorbers it's still open cell absorption is still described as an inefficient application contradicting acoustic. The Modex system of RPG is based on a typical membrane approach. The Pro-Corners of RPG date most likely from AFTER this text is written.
And I'm sure that Dr. Peter D'Antonio and Trevor Cox have as much access to Studio related literature than Max.

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Read as:
In the most recent Dr. Peter D'Antonio and Prof. Dr. Trevor Cox book about absorbers corner absorption based on open cell absorption is still described as an inefficient wrong application in function of acoustic wave behavior in corners.
The back then existing Modex system of RPG is based on a typical membrane approach. The Pro Corners of RPG date most likely from AFTER this text is written.
And I'm sure that Dr. Peter D'Antonio and Prof. Dr. Trevor Cox have as much access to Studio related literature than Max.

Edited by Hugh Robjohns (11/08/06 09:22 AM)

This thread isn't complete related to exact info and context.

The original message shown here is in reply to and triggered by a message of Hugh including his reference to Max. This post included related info, references and comments.
The neutal reference to that post is removed from my post. (Edit first message)

And the post with the historical correct description about the the LENRDs and the related acoustic effect in function of corner absorption is also gone.
That post relates directly to the historical context of the use of corner absorption in this studio world.

The post I clearly state my appreciation for the tutorials by Zukan to prevent any confusion is also gone.

I probably look wrong but I can't see what the edit in the second post is or refers to.

Eric

Good point. Here is my earlier contibution. It was only left off this thread initially because when I dissected the original debate not all the relevant posts had been sent as 'reply to' and thus 'fell off' the threaded chain. The relevant context of the discussion can still be found on the DIY sticky thread at the top of the page should anyone be interested.

Quote EGAM:

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Max knew very well how they were called and what the exact origin is of this design.

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Max is unable to post here himself at the moment as he is recovering from an operation.... but as I understand it, Max argues that while the NAME did originate at studio-tips, the core IDEA did NOT. The application of absorption material like this has been around for a long, long time -- certainly pre-dating the Internet, never mind studio-tips. This can be referenced with plenty of other respected and long serving studio designers and installers, Whitemark, Andy Munroe, and so on.... They have all used designs similar to this at one time or other...

I'm also sure that Max has never claimed to have invented either the idea or the name.... and 'super chunks' is a natural contraction and somewhat easier to say than Studiotips Super Chunks -- I don't think anyone means any disrespect by shortening the name for convenience.

Hope that clarifies things a little...

Hugh

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Technical Editor, Sound On Sound

Quote EGAM:

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I probably look wrong but I can't see what the edit in the second post is or refers to.

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There is no editing of your text. The message is simply there to reflect that fact that I dissected the post from the original DIY thread and re-posted here under a new topic title.

hugh

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Technical Editor, Sound On Sound

I am unable to move the original post into this thread, but for the sake of completeness, here is the unexpigated content of the two posts that Eric refers to above...

Quote EGAM:

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To prevent confusion.

I do like the clear and nice tutorials from Zukan, making them important to link to or make them a sticky.
I did not introduce Max's name in this thread.
And it's because that those tutorials are valuable, I believe they should be correct.

My original response was nothing else than related to the name used for those chunks.
http://www.soundonsound.com/forum/showthreaded.php?Number=336537

And I still believe Studiotips, the related contributors and its owner have the right to.
I shouldn't need to defend this.

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Quote EGAM:

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PS:
The eldest typical Corner absorbers and (pseudo) related measurments I found on the net (at least as far as I can judge) are the Auralex LENRDs. But back then when I was on the net it was clear to me that Auralex had Corner Absorbers without knowing or being aware of the typical acoustic behavior of corner absorption.
This becomes clear beyond any doubt by checking the constructive related discussions I had on the net with them
And that are also people long busy with Studio related acoustics no?
It's not because someone put some absorption in a corner because it is a practical or estethic place to put it as part of a bigger whole that they applied corner absorption.

The Modex of RPG was designed as corner absorber, but therefore specific designed as membrane absorber.

A wheel existed from the moment that people understood that a piece of this round tree could be used as a wheel to move things. Not from the moment the tree existed.

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Technical Editor, Sound On Sound

Edited by Hugh Robjohns (11/08/06 03:57 PM)