I didnt say it gives a plastic sound. Any material on the softer side will lack high frequencies thats why this isnt an ideal material.
Audiofrenzy.
I have never tried correx , the thicker proplex which is of a similar construction sounds very good.
But it is quite heavy.
It has a full frequency up to 20k and above.
With the low grade EPS you need to use my secret methods to increase the HF to 20k 😃
Steve.
I have never tried correx , the thicker proplex which is of a similar construction sounds very good.
But it is quite heavy.
It has a full frequency up to 20k and above.
With the low grade EPS you need to use my secret methods to increase the HF to 20k 😃
Steve.
I havent tried thick proplex maybe its denser then the correx?
Steve , you dont have any secrets, you post all your info on the forums. lol Soda can technique?
That is just one of the many factors involved in building a good sounding DML panel. The most important is the panel material. If you cant even get the foundation right nothing else will matter.
Audiofrenzy
The flutes on the thicker proplex are much stronger , not sure about the material used.
Correx is a lot thinner , but I think the thinner proplex might be similar to the correx?
I am in no hurry to try the thinner correx ,but will give it a try if I come across it in a bin 😄.
The coffee whizzer I used was for the harder panels, such as ply, and would be not suitable for EPS.
I think I might have posted the method I used for EPS, but I can't remember?
My memory is getting very bad, but it was never very good to start with 😊.
There is a lot of talk about bad echo on EPS , do your panels suffer from this ?
Steve.
The flutes on the thicker proplex are much stronger , not sure about the material used.
Correx is a lot thinner , but I think the thinner proplex might be similar to the correx?
I am in no hurry to try the thinner correx ,but will give it a try if I come across it in a bin 😄.
The coffee whizzer I used was for the harder panels, such as ply, and would be not suitable for EPS.
I think I might have posted the method I used for EPS, but I can't remember?
My memory is getting very bad, but it was never very good to start with 😊.
There is a lot of talk about bad echo on EPS , do your panels suffer from this ?
Steve.
That's the thing, and the problem, is the material for the DML panel. One at least knows the specifications of the exciter, but one never knows the specifications of the material, just some material picked from the rubbish bin or from the street. EPS or XPS producers don't give any specifications relevant to audio signals, but only relevant to heat transfer, such as thermal Conductivity, R-value and standard physical values needed for construction sector, such as the density and the weight/m2. So, the person sticking the exciter to found-in-the-rubbish-bin EPS sheet is like "a blind man in a dark room looking for a black cat which isn’t there." (Nothing against the blind people!)
Those companies, which used polystyrene panel for their flat panel speakers, never gave the specifications of that panel. They never even mentioned the material was EPS or XPS, or even why the depths and heights in the back of the panel, or any dimensions of those hills and valleys. All of these companies died away anyhow. (Sure, Tectonic and Amina Sound is still there.)
The so-called flat EPS panel is never fully flat on any side. You push a finger in, and the dip stays on the surface. For construction purposes, those surface irregularities is not a problem, but something good, the render, or the screed or the concrete will take care of that.
The thing is, if you want an EPS sheet to be the loudspeaker, you have to get the specifications needed for audio from the manufacturer of the sheets. I don't think any manufacturer would have any. Some might have some sound damping specifications, but that would be quite rare. For example, you can call Kay-Metzeller for EPS (tech. support: 01245 342104 UK), or Cellecta who does only XPS ((tech. support: 01634296677 UK). There's also Kingspan, Dow Chemicals, Polyfoam, Ravatherm, Soprema, Sundolitt etc for XPS. There's Springvale, Knauf, Bewi etc for EPS. That way, you'd get a EPS (or XPS) panel with specifications that can be used for experimentation.
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Chdsl.
You have as much chance at finding the best sounding panel in a skip as you have ordering expensive materials in a shop or on line.
Most materials need tweaking to get the best sound from them as well.
Good luck finding a panel with a spec sheet for the best possible sound .
Steve.
You have as much chance at finding the best sounding panel in a skip as you have ordering expensive materials in a shop or on line.
Most materials need tweaking to get the best sound from them as well.
Good luck finding a panel with a spec sheet for the best possible sound .
Steve.
Instead of finding EPS sheets at rubbish bins, why don't you call the technical support of the manufacturers? You have to know what is EPS to begin with. It is made for construction purposes. The packaging is made only on contract and on client's specifications.
You can't just go and stick the exciter on the back of any by-chance-found sheet and try to get the best sound out of it. The next by-chance-found-sheet might give better sound. No concrete ending of the process. 🙂
It is you, who is selling the EPS for DML idea, not me. EPS is made mainly for construction purposes. If you want to get an EPS sheet to work with your exciter, you have to get that sheet made for that. You have to give them the specifications and pay for it. If you are adamant in using EPS sheet for a DML, you can go for it, but you'd never get rid of the tunnel effect. To get rid of the tunnel effect, you have to get rid of the width of the sheet, which is pretty hard for EPS, as it would crack. The best sheet for a DML is a very thin, very light material, which would come back to its former position, once the force is taken off. There's whole lot of such materials at B&Q, have a look.
Chdsl.
I tried, but I can't listen to any more BS.
Now, where is that off button.
Steve.
I tried, but I can't listen to any more BS.
Now, where is that off button.
Steve.
Me too! 🙂
Learn about the material before talking about it. You don't know anything about EPS, how it is made, why it is made and so on. EPS is a thermal insulation and sound insulation material.
The crates I managed to find at the local shop were not 3ply .
I could have sworn they were .
Not that it would have been a problem, but the edges were not straight.
But they will make great kindling for the fire.
I think the 3 ply they use in the crates are some sort of flexible ply.
I need some more if I am going to make some canvas panels for my friend.
Steve.
I could have sworn they were .
Not that it would have been a problem, but the edges were not straight.
But they will make great kindling for the fire.
I think the 3 ply they use in the crates are some sort of flexible ply.
I need some more if I am going to make some canvas panels for my friend.
Steve.
If the flutes are thicker and much stronger on the proplex that is the reason it sounds better then the Correx.
No. Damping factors help reduce echo like the pva/water mixture , paint and foam around the edges of the panel.
Yes, polypropylene is indeed made of carbon and hydrogen. As is polystyrene. Chemically, PP is (C3H6)n, and PS is (C8H8)n. So both are made of exactly the same stuff, just arranged a different way.
And polypropylene is absolutely, positively, undeniably "plastic" (also just like PS in that respect). It's as "plastic" as a thing can be.
Did you mean PP is not foam? That is usually (but not always) true.
Eric
There are no specifications on EPS when it comes to using it as a diaphragm for a loudspeaker. EPS and XPS were made for construction use and packing.
Dr.Jose Bertagni has many patents you can read up on that tells about the diaphragm.
EPS may not be ruler flat but its flat enough. EPS is also very fragile depending on the grade/density of the EPS. Low grade EPS is to soft which I have mentioned many times before. This is the reason why I recommend the higher grades of EPS. But even the higher grades can still be damaged with little force. Even Magnepans diaphragm I am sure is fragile.
If one wants to use EPS as a loudspeaker diaphragm then one needs to ask those that actually built a good sounding DML loudspeaker and not the manufacturer.
No one is selling anything here. We do what sounds best to us. This is the reason I suggest sound clips/vids so others can get the gist of the sound and decide for themselves if they like that sound.
There are many ways to reduce the tunnel effect.
What is this "best sheet" called? Did you try it? If so what are the results?
Well, for those who wants to stick an exciter to a panel, a video from those who actually sell flat DML speakers,
(It is in Russian, so use subtitles)
This is more or less their latest product. In this video, he stands and covers the speaker with his body, but the sound comes through, just to prove a point. They have been making flat DML speakers for few years.
Here's one of their patents of an earlier product. The actual product image is in the patent. You'd have to use a translator read it. You'd be surprised to notice how detailed the description of the patent. Google translates pretty well, but to get the feeling, best read it in Russian. (I speak many languages.) The main sound transfer material (to air) is paper (30 to 125g/m2). To build that speaker, you get everything in that patent, length, breadth and whatnot. You'd have to spend some money build something. Try a few times, fail a few times until you get it going.
Aha, I'm not going to build it, well at least not yet, until I read all the patents. By the way, that guy in the video is the inventor.
You can find all their videos here.
This is more or less their latest product. In this video, he stands and covers the speaker with his body, but the sound comes through, just to prove a point. They have been making flat DML speakers for few years.
Here's one of their patents of an earlier product. The actual product image is in the patent. You'd have to use a translator read it. You'd be surprised to notice how detailed the description of the patent. Google translates pretty well, but to get the feeling, best read it in Russian. (I speak many languages.) The main sound transfer material (to air) is paper (30 to 125g/m2). To build that speaker, you get everything in that patent, length, breadth and whatnot. You'd have to spend some money build something. Try a few times, fail a few times until you get it going.
Aha, I'm not going to build it, well at least not yet, until I read all the patents. By the way, that guy in the video is the inventor.
You can find all their videos here.
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I have been watching them from around 5 years ago. They are called Sheet Control or Mescalito speakers.
Also if you dont want to DIY, they actually SELL there speakers.