I guesstimate needing more like 1/2" squares if this is to be done effectively with totally flat elements in an array. Yes, very limited. I think if curved segments are out, electrostats are out.
This was my primary concern before posting this.
I'm not sure I get what you're saying.. All you can get with a plasma driver is a 360° cylindrical wave, right? If I need to shape that into 1/8-sphere, that can be done more easily with more conventional drivers, unless you're talking about an array of plasma drivers, which I have never, and still haven't, even imagined as type this.
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Yes, but I think something of the correct shape moving as a piston might be sufficient for good results, and maybe even a fairly crude approximation of a piston. I may be wrong, and it would obviously depend on size and precision.
Quote~"I'm not sure I get what you're saying.. All you can get with a plasma driver is a 360° cylindrical wave, right?"
No, if you have a Plasma driver that has a point or a needle that is active, then it will emit the sound in a spherical form for 360 degrees all of the way around from any angle as it is a single point.
jer
No, if you have a Plasma driver that has a point or a needle that is active, then it will emit the sound in a spherical form for 360 degrees all of the way around from any angle as it is a single point.
jer
Actually, if you wanted to create a good approximation of an eighth of a sphere, you only need to make ESL panels the correct size & shape of a segment of a geodesic dome the size of the sphere you wish to approximate. Making modest sized hexagonal ESL panels shouldn't be too much harder than the "normal" square, or rectangular ones that are common. I'm not sure how much more effective that approach would be than just angled square panels, but I suppose it would come closer to the ideal. The real question is, would the human ear really be able to tell the difference?
Hi,
dumptruck, Your Q in itself was not offensive, but rather it's style.
No initial hello, no complimentary close, just a rudimentary Q and a short command. Well that might be perfectly suitable at the drill ground, or for a pet obedience school, but over here we usually appreciate a more civilian style.
Did You really expect a long elaborated answer to Your Q?
You got an A in a Wysiwyg style.
And it took till #15 for us to learn that sonic qualities don't matter, that the Q is just a principle one.
I'm sorry though, as I erred with the meaning of the word crude. I thought it had a much softer meaning (as the smiley at the end should have told).
Anyway, back to Q.
The stators for such a convex shape should give not too great problems.
Punched metal sheets could be formed into a convex shape for smaller sizes and arrays of smaller segments coud be used for larger structures.
The latter could be flat segments featuring simple flat membranes too.
Here one needs to deal with lobing and venetian blind effects.
The former would be more difficult, as the membrane needed to take up a convex shape also. This in turn would probabely rule out mechanical tensioning out of two reasons.
The major issue would be that mechanical tension would 'destroy' the convex shape.
The second reason could be, that if the membrane were kind of welded together from multipe stripes to achieve the domed shape, it' d probabey not strong enough any more to take sufficiently high tensioning forces.
Instead I assume a solution asked for a panel design that doesn't require mechanical tensioning. There have been ideas to achieve this aim and I've experimented in this field years ago also.
It'd require multiple spacers or standoffs that support the membrane at very many points. The free distance between adjacent spacers probabely spaced no more than 5-10mm apart.
If one used punched metal stators for example small enhanced dots/bumps positioned on each "cross" between the holes could keep the required d/s.
Alternatively a mesh made from thin foam with very high compliance and high epsilon value might be useable.
In theory a foam mesh even features quite a row of advantages for any ESL panel.
It'd allow for easy mounting, no mechanical tensioning rigs woud be needed.
It'd allow for higher efficiency and maximum SPL if foams of high epsilon would be used and due to increasing bias voltages.
It' d introduce alot of damping, which gives a clean HP-response without the usal very pronounced resonance. As such dynamic stability woud be no issue as well as other base resonance related issues could be omitted with.
The absence of mechanical tension and the damping would oppress partial movements of the diaphragm.
Heck, it would even allow for flexible panels
Unfortunately theory and praxis agreed to differ from each other.
jauu
Calvin
dumptruck, Your Q in itself was not offensive, but rather it's style.
No initial hello, no complimentary close, just a rudimentary Q and a short command. Well that might be perfectly suitable at the drill ground, or for a pet obedience school, but over here we usually appreciate a more civilian style.
Did You really expect a long elaborated answer to Your Q?
You got an A in a Wysiwyg style.
And it took till #15 for us to learn that sonic qualities don't matter, that the Q is just a principle one.
I'm sorry though, as I erred with the meaning of the word crude. I thought it had a much softer meaning (as the smiley at the end should have told).
Anyway, back to Q.
The stators for such a convex shape should give not too great problems.
Punched metal sheets could be formed into a convex shape for smaller sizes and arrays of smaller segments coud be used for larger structures.
The latter could be flat segments featuring simple flat membranes too.
Here one needs to deal with lobing and venetian blind effects.
The former would be more difficult, as the membrane needed to take up a convex shape also. This in turn would probabely rule out mechanical tensioning out of two reasons.
The major issue would be that mechanical tension would 'destroy' the convex shape.
The second reason could be, that if the membrane were kind of welded together from multipe stripes to achieve the domed shape, it' d probabey not strong enough any more to take sufficiently high tensioning forces.
Instead I assume a solution asked for a panel design that doesn't require mechanical tensioning. There have been ideas to achieve this aim and I've experimented in this field years ago also.
It'd require multiple spacers or standoffs that support the membrane at very many points. The free distance between adjacent spacers probabely spaced no more than 5-10mm apart.
If one used punched metal stators for example small enhanced dots/bumps positioned on each "cross" between the holes could keep the required d/s.
Alternatively a mesh made from thin foam with very high compliance and high epsilon value might be useable.
In theory a foam mesh even features quite a row of advantages for any ESL panel.
It'd allow for easy mounting, no mechanical tensioning rigs woud be needed.
It'd allow for higher efficiency and maximum SPL if foams of high epsilon would be used and due to increasing bias voltages.
It' d introduce alot of damping, which gives a clean HP-response without the usal very pronounced resonance. As such dynamic stability woud be no issue as well as other base resonance related issues could be omitted with.
The absence of mechanical tension and the damping would oppress partial movements of the diaphragm.
Heck, it would even allow for flexible panels
Unfortunately theory and praxis agreed to differ from each other.
jauu
Calvin
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