Trying the ZR Acoustics Panels

cal3713

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So clearly the ZR panels do something to improve the bass - what, beyond what the manufacturer says I don't know. And I don't think Hanson Hsu is going to reveal any more than he already has. He seems to be very smart about protecting his trade secrets.
I'll just note that one can read reports of super-tweeters improving subjective bass performance (e.g., https://theartofsound.net/forum/showthread.php?46702-Supertweeters)... so it is possible for the perception of bass to be impacted by devices which only affect higher frequencies.
 
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MPS

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My motivation would be to show people who haven't experienced the product yet just how effective it is at dealing with room reflections, especially considering it's something that seems to defy common acoustical intuition in regards to bass absorption due to its svelte profile.
That would be really exciting, a slim, flat and attractive looking product that can supply effective LF absorption.
Where I live most rooms/houses suffer from excessive LF energy and room modes due to construction methods of local buildings.
In my system the low mode sits in at about 37Hz but anything under ~200Hz mostly needs absorption so such products are very welcome. Now if we could get some measurements...
 
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Cellcbern

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BTW I'm not trying to put down the product, all I know it might be excellent and suit multiple purposes. It's even very likely that those panels can be beneficial in typical untreated environment but at the same time it's impossible to say if they are the best or even relatively good. If anything, acoustic environments vary and that means there is no single one solution that suits all.
It's the lack of information that makes it very difficult to be useful for it's intended purpose. Acoustic designers need to stick to known items or design such for themselves.
It would be very welcome if one or more users could bring in their measurements treated/untreated, just to give a rough idea of the effects of the treatment.

No reflexions in the room would mean anechoic chamber and that definitely is not wanted. A smooth and reasonable 200-400ms RT60 values are in the ballpark for stereophonic music listening room.
I have no doubt that you are happy with the result and the treatment is working in your case but at the same time that's about all we know.
My experiences with the ZR panels are not "all we know". I have posted reviews from both consumer audio and pro audio publications, and provided the link to an extensive film/recording/mastering lab client list with project summaries and comments on each. There is additional information online and at the DHDI website including testimonials, interviews, and comparative musical performances with and without the ZR panels. The ZR panels reduce/eliminate reflections without creating a dead acoustic much less an anechoic chamber. That's clear from both my experiences with them and comments from DHDI's commercial clients. Not sure how relevant RT60 values (which are measures of reflected sound) are to a panel that eliminates reflections. Like most posters your comments are from the perspective of conventional acoustics which may limit their relevance. I can't help you with measurements and am not aware of any having been published. Anyone who has to have measurements before purchasing acoustical panels should probably look elsewhere.
 

Cellcbern

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My motivation would be to show people who haven't experienced the product yet just how effective it is at dealing with room reflections, especially considering it's something that seems to defy common acoustical intuition in regards to bass absorption due to its svelte profile.
That's your stated motivation - I'm not sure what motivation DHDI would have. They don't even market to the home audio market. Again, I stumbled on these, decided to try them, got great results, and shared my experiences. I didn't take or want any measurements, and wouldn't take any if I had to do it all over. My ears told me all I needed to know. Anyone who has to have measurements before trying/deploying acoustical treatments should probably look at something else.
 
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MPS

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My experiences with the ZR panels are not "all we know". I have posted reviews from both consumer audio and pro audio publications, and provided the link to an extensive film/recording/mastering lab client list with project summaries and comments on each. There is additional information online and at the DHDI website including testimonials, interviews, and comparative musical performances with and without the ZR panels. The ZR panels reduce/eliminate reflections without creating a dead acoustic much less an anechoic chamber. That's clear from both my experiences with them and comments from DHDI's commercial clients. Not sure how relevant RT60 values (which are measures of reflected sound) are to a panel that eliminates reflections. Like most posters your comments are from the perspective of conventional acoustics which may limit their relevance. I can't help you with measurements and am not aware of any having been published. Anyone who has to have measurements before purchasing acoustical panels should probably look elsewhere.
Point taken. I even went to see the manufacturer's web pages, didn't find any much information from there but I also failed to see any definitive claims as far as acoustic properties of the product is concerned. I actually don't have anything against their products, all I'm saying is that I don't understand their functioning or effects on room acoustics.
It may just be me and those who know better don't experience my limitations.
 

Cellcbern

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Point taken. I even went to see the manufacturer's web pages, didn't find any much information from there but I also failed to see any definitive claims as far as acoustic properties of the product is concerned. I actually don't have anything against their products, all I'm saying is that I don't understand their functioning or effects on room acoustics.
It may just be me and those who know better don't experience my limitations.
What's on the website is what DHDI is willing to share. I suspect that clients get more information if it exists, but Hanson Hsu has also been quoted as saying that they hadn't yet perfected techniques to measure what the ZR panels do. For me the extensive list of high profile clients provided all of the comfort I needed. Let's take just one client - McGill University in Montreal - which has one of the world's top programs in audio and acoustical engineering. It is inconceivable to me that McGill would be using DHDI's ZR technology if it did not work as advertised:

 

MPS

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What's on the website is what DHDI is willing to share. I suspect that clients get more information if it exists, but Hanson Hsu has also been quoted as saying that they hadn't yet perfected techniques to measure what the ZR panels do. For me the extensive list of high profile clients provided all of the comfort I needed. Let's take just one client - McGill University in Montreal - which has one of the world's top programs in audio and acoustical engineering. It is inconceivable to me that McGill would be using DHDI's ZR technology if it did not work as advertised:

Yes, I'm sure they do function as designed. DHDI will of course share the information which they wish, it's only that there is stark contrast in sharing compared to other well known manufacturers. Take RPG Acoustical Systems for example: https://www.rpgacoustic.com/data-sheet-library/
 

Cellcbern

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Yes, I'm sure they do function as designed. DHDI will of course share the information which they wish, it's only that there is stark contrast in sharing compared to other well known manufacturers. Take RPG Acoustical Systems for example: https://www.rpgacoustic.com/data-sheet-library/
Yep. On the other hand, RPG's room treatments are all conventional and lend themselves to conventional measurements, which means measurements of reflected sounds. If you outfit a whole room/studio with Zero Reflection panels it is possible that conventional measurements don't yield clear or meaningful information.
 
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Cellcbern

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I'll just note that one can read reports of super-tweeters improving subjective bass performance (e.g., https://theartofsound.net/forum/showthread.php?46702-Supertweeters)... so it is possible for the perception of bass to be impacted by devices which only affect higher frequencies.
Maybe. But keep in mind that the posters saying the ZR panels don't/can't impact the lower frequencies have no direct experience with them - they are speculating. However the ZR panels accomplishment it, my experience with them and the comments from reviewers and DHDI's clients confirm that they make significant improvements in the bass.
 
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MPS

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Maybe. But keep in mind that the posters saying the ZR panels don't/can't impact the lower frequencies have no direct experience with them - they are speculating. However the ZR panels accomplishment it, my experience with them and the comments from DHDI's clients confirm that they make significant improvements in the bass.
I need to agree that experience overrides speculation.
 

Tim Link

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That's your stated motivation - I'm not sure what motivation DHDI would have. They don't even market to the home audio market. Again, I stumbled on these, decided to try them, got great results, and shared my experiences. I didn't take or want any measurements, and wouldn't take any if I had to do it all over. My ears told me all I needed to know. Anyone who has to have measurements before trying/deploying acoustical treatments should probably look at something else.
Nothing wrong with that. As an end user there's no onus on you to make measurements. You can just enjoy the benefits that you readily perceive. Some of us are geeky about numbers. If we're curious enough we'll get the panels and measure them ourselves. If DHDI normally sells the panels under their consultation then there's no need for them to give specific details of their operation.
 
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Duke LeJeune

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Not that I have a dog in the fight, but imo one way the DHDI panels MIGHT work is by de-correlating the back-and-forth movements of the air molecules which normally oscillate in unison to create the compressions and rarefactions that make up a sound wave. I'm not acoustician enough to think through all the implications of this, but it seems to me that sufficient randomization of the movements of the air molecules would significantly decrease the net sound pressure reflected.
 
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Carlos269

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Not that I have a dog in the fight, but imo one way the DHDI panels MIGHT work is by de-correlating the back-and-forth movements of the air molecules which normally oscillate in unison to create the compressions and rarefactions that make up a sound wave. I'm not acoustician enough to think through all the implications of this, but it seems to me that sufficient randomization of the movements of the air molecules would significantly decrease the net sound pressure reflected.

Part of the issue with the technical claims of the panels is that coincident sound waves experience no absorption, reflections or diffusion, but are rather “deconstructed” through quantum methods. Based on the first law of thermodynamics, the law of conservation of energy, the sound waves’ energy needs to be accounted for and I doubt that it is all getting converted to heat or dark matter on these panels.
 
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Duke LeJeune

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Part of the issue with the technical claims of the panels is that coincident sound waves experience no absorption, reflections or diffusion, but are rather “deconstructed” through quantum methods. Based on the first law of thermodynamics, the law of conservation of energy, the sound waves’ energy needs to be accounted for and I doubt that it is all getting converted to heat or dark matter on these panels.
Notice that I made no attempt to explain what might be happening in terms that DHDI uses. I started out with this question in mind: "IF this geometry DOES have a significant beneficial effect, how MIGHT that happen?" Chances are I am wrong of course.
 
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Cellcbern

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Notice that I made no attempt to explain what might be happening in terms that DHDI uses. I started out with this question in mind: "IF this geometry DOES have a significant beneficial effect, how MIGHT that happen?" Chances are I am wrong of course.
If thousands of non-parallel surfaces per sf is what makes the ZR panels work (as per the manufacturer) then the geometry doesn't just have "a significant beneficial effect", the geometry is the entire story. Note that DHDI claims that the panels can be made much thinner (as long as the geometry is maintained?) and now features a 1.6mm thick version that can be embedded in window curtains:


ZR technology is either a complete snow job that has duped dozens of top film/recording/mastering engineers/labs/studios, or it is a completely new and different technology from conventional acoustical room treatment. In light of the client list, the reviews, and my own experience I would vote for the 2nd possibility. And if it is the 2nd possibility then you can't adequately describe/explain/measure how it works just using the concepts, terminology, and tools of conventional room acoustics as most people posting about it want to do. Keep in mind that DHDI is first and foremost an architectural practice. If a design/installation doesn't work as promised you don't get additional jobs.
 
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Cellcbern

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Part of the issue with the technical claims of the panels is that coincident sound waves experience no absorption, reflections or diffusion, but are rather “deconstructed” through quantum methods. Based on the first law of thermodynamics, the law of conservation of energy, the sound waves’ energy needs to be accounted for and I doubt that it is all getting converted to heat or dark matter on these panels.
The explanation from Hanson Hsu as I understand it is that energy is dissipated with each bounce (of an air molecule) off of a non-parallel surface, which would account for what happens to a sound wave's energy. With multiple bounces too much energy is dissipated for a reflected sound wave to form. That's pretty straightforward and makes sense to me. This excerpt, which provides a similar explanation, is from the 10/15/2008 ProSound News article, Review: Delta H.Design ZR Acoustics Treatment Philosophy:

"....To demonstrate the movement of a series of his algorithmically aimed, ever-diminishing reflections — the essence of ZR — Hanson deliberately and precisely draws virtual ray traces through the air, counting “one bounce — down 6dB. Two — down 12dB. Three — down 18dB. Four — down 24dB. Five — down 30 … And now we’re into the noise floor before it ever makes it back to your ears.....”
 
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Cellcbern

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The problem is the windows are directly behind the speakers. I have played with their placement and due to the dimensions of the room, adjusting the width of the speakers in either direction do not sound (or measure) as good. There is more flexibility in moving them forward or backward, but they sound best where they currently sit.

There are still some reflection issues but as I have added drapes and padding under the floor rug, it has made small improvements. Will try to keep playing with the panel placements and see how they sound directly (4 panels together) behind each speaker or all grouped in the center.
This is new - ZR technology embedded in window curtains. Might be a solution for your window issues:

 

Motoman

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I have a small dedicated room, 11x11x11, with a 3x3 window on one of the side walls. I have no treatment now, but have been looking, and I am going to try the ZR panels. I wonder how many I will need . . . two big ones, four 24x24 . . .? The explanation of how they work strikes me as plain old gobbledygook -- a bunch of complicated pseudo-scientific nonsense to confuse a reader -- reminds of the MIT "poles of articulation" nonsense -- which cables many like regardless of explanation. However, it seems as if, regardless of how they work, they do apparently "work," which is all that I care about. I don't need to know how the circuit boards in my Pass Labs X250.8 work, just that they do. I am interested to see what the ZR will do for my reflective room!
 
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cal3713

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This is new - ZR technology embedded in window curtains. Might be a solution for your window issues:

I would absolutely love it if these worked, although again, I just don't see how the physics of it is possible.

The demonstration I'd like to see is a youtube video of one of these curtains being draped over a playing speaker. If they do what they say, it should immediately mute the speaker, no? Or at least produce an XX db drop in sound...

This would be super persuasive and drive a ton of sales.
 

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