The vibration model of the panels must be the same as Chladni Plates I assume. I do not remember anyone making that analogy, my bad if it's mentioned before.
For reference: YouTube
There would be also interesting to treat panels as musical instruments. Like guitar body or piano soundboard.
For reference: YouTube
There would be also interesting to treat panels as musical instruments. Like guitar body or piano soundboard.
My first test pair done...
Hi all,
It's been a while but I've finally managed to finish my first test pair. They are small'ish carved XPS panels (350mm X 560mm) suspended within a hardwood frame, polyfill and cork backed because I want them to be wall mounted.
They sound very good paired with a small subwoofer but they did lose a tiny bit of magic when I closed up the back.
Attached is just a few quick pics and a REW measurement.
........on to the next panels
Hi all,
It's been a while but I've finally managed to finish my first test pair. They are small'ish carved XPS panels (350mm X 560mm) suspended within a hardwood frame, polyfill and cork backed because I want them to be wall mounted.
They sound very good paired with a small subwoofer but they did lose a tiny bit of magic when I closed up the back.
Attached is just a few quick pics and a REW measurement.
........on to the next panels
Attachments
Thank you, the measurement is with the back on. The panel is suspended by a bead of silicone on top and bottom tabs.
Attachments
Hi all,
It's been a while but I've finally managed to finish my first test pair. They are small'ish carved XPS panels (350mm X 560mm) suspended within a hardwood frame, polyfill and cork backed because I want them to be wall mounted.
They sound very good paired with a small subwoofer but they did lose a tiny bit of magic when I closed up the back.
Attached is just a few quick pics and a REW measurement.
........on to the next panels
Here are 2 tips.
1. you could of left the back open and put 1-2inch spacers (with foam) to get some of that bipolar magic back.
2. If the wood frame is touching the wall it will vibrate the wall so some type of foam damping can be used in the back on each corner.
Also is that Grill cloth? If so you are the first person that I've seen (besides myself) use grill cloth. Grill cloth can help in taming the sound of the panels making them sound less harsh.
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@JMatt - great looking panels and the measurements looks good too.
JMatt's panels certainly looks great with the grill cloth. I assume that grill cloth does not dampen the panels as much as canvas (OffGridKindaGuy's panels). DMLBES - do you actually glue the grill cloth to the panels?
Yes you are correct, grill cloth has WAY less dampening properties then canvas.
I just make framed grill cloth covers like most conventional boxed speakers use. You can glue the cloth directly to the panels but like I said before any adhesive you use can add more damping. Other options is to glue it to the panels frame. You can also make a sock like wrap around cloth cover used in (bipolar) speakers like Def Tech, Mirage, etc.
Hi,
I am getting confuse over the terms used describing DML speakers being bipolar?
If one says the speaker is bipolar then both the front surface and back surface have to be 180 degrees in or out of phase. How does the audio exciter accomplish this if the exciter is moving forward the front surface is generating a compression wave and the back surface is generating a reification wave is this not a dipole like a magnapan or electrostatic speaker? How do you move the front and back surface in opposite direction at the same time with one exciter?
I am getting confuse over the terms used describing DML speakers being bipolar?
If one says the speaker is bipolar then both the front surface and back surface have to be 180 degrees in or out of phase. How does the audio exciter accomplish this if the exciter is moving forward the front surface is generating a compression wave and the back surface is generating a reification wave is this not a dipole like a magnapan or electrostatic speaker? How do you move the front and back surface in opposite direction at the same time with one exciter?
Not to be argumentative but from what the literature is showing is a dipole have equal polar lobes but they are 180 degrees out of phase. The bipole has equal polar lobes just as a dipole but the lobes are in phase. So to create a bi pole speaker one would need two exciters that were on opposite side and wired opposite so that each side would be in phase or bipole. For panels that are driven by exciters on one side it would have to be a dipole and the side with the exciter would have a higher SPL than the opposing side since there would be attenuation going through the panel.
Tagis, you're correct. DMLBES is not. The DML is chaotic, it isn't phase coherent so it is not a bipole in the acoustic sense.
Are you sure about that? Tell me why he is correct and I am wrong? You just a troll want to start shiznit instead of trying to solve the problem with nothing to offer as usual. LOL
Even your Buddy Burnt says they are Bipolar. SMDH
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There's plenty of published stuff on DMLs about the chaotic nature of their radiation.
A bipolar is classically demonstrated by two moving coil drivers, one front, one back, both radiating in phase. Ie they both push or pull at the same time.
A dipole on the other hand can be as little as one driver on an open baffle. Front and back radiation in opposing phase. Front pushes while rear pulls.
The DML panel is excited by a random chaotic pattern of vibration. It is a completely different mode of operation.
Clearly whatever one side of the panel is doing, the other side will be doing the opposite, as the panel retains its thickness while vibrating. It behaves like a dipole at all points. At a low enough frequency it behaves as one large dipole. What it does, as a whole, at other frequencies I don't know.
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There are plenty of published stuff on DML's being bipolar just ask Burnt. lol
NO ****, that's what I said. Bipolar means sound is radiated from the front and back equally. Which means they are in phase. SMDH
Dipole means out of phase. SMDH
Tagis said they are dipoles.
You are saying they are neither. What mode of operation are they? and please don't say chaotic. LMAO
THis is what Burnt wrote>
WTH? So at low frequencies they are dipole but at other frequencies as a whole you don't know? SMDH that is far from being clear. LOL
This looks quite "not-quite-dipolar chaos" to me, but then again I do not know what I'm talking about.
An externally hosted image should be here but it was not working when we last tested it.
