Hi,
Quite simply :
if the diaphragm is made of unobtainium that is infinitely stiff,
rotation of the diaphragm will produce no bass whatsoever.
The claimed subwoofer applications for the operating principle, e.g. :
An externally hosted image should be here but it was not working when we last tested it.
simply will not work. There is nothing to discuss about the basic
physics in the bass, it is not a voltage to pressure transducer.
There is nothing here that reduces the need for boxes for bass.
rgds, sreten.
(I never said it won't make some noise, it will, but I'm not
interested in something so fundamentally misrepresented.)
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Mad? As in Dragoslav Colich? He lives and works a couple of miles from my home but I have never heard his designs. He now owns a consulting business in Irvine.
If you have seen my speaker system on this website, you will see that I'm a big fan of BG Radia Planar Magnetic drive units. The Mad designs look cosmetically very similar.
As far as the DDD and Walsh drivers go, I understand that they operate in a pistonic manner up to a point, then will start to bend at a critical frequency. Correct? Jordan controflex cones are somewhat similar? There just seems to be an element of chaos involved that the best math can't overcome..
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The DDD does not work pistonic but produces 'bending waves' that ripple from the voice coil through the material to the surround where they are absorbed. The bending wave causes sound to radiate radially in a horizontal plane.
The DDD looks superfically like a cone pointing downwards, but it is not a piston. The flare and angle is more like a mildly flaring cone than a piston in shape.
jan didden
The DDD looks superfically like a cone pointing downwards, but it is not a piston. The flare and angle is more like a mildly flaring cone than a piston in shape.
jan didden
Read this..
German Physiks - High End Technology Loudspeaker Manufactur - DDD Driver - The DDD Driver
Jordan cones are sort of like a DDD cone, but used conventionally. At a certain critical frequency, they start to bend and produce the higher frequencies in a somewhat even manner, instead of a rigid cone that has one big resonant peak..
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Hi,
The DDD driver inherently must have a pistonic region of operation at the low end.
rgds, sreten.
The DDD driver inherently must have a pistonic region of operation at the low end.
rgds, sreten.
An externally hosted image should be here but it was not working when we last tested it.
Yes, this is the driver I mentioned... Unfortunately, this guy never answers my request for a couple of this planar driver... The radia BG are unfortunatey poorly manufactured and you can easily spin the driver on his axis, this gives you an idea of its rigidity. If you have the opportunity to listen or try the MAD please let me know your feelings...
It's correct that the Walsh and the DDD have both a pistonic "range"... Then this is another difference with NXT/BMR drivers !...
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Maybe a nice subwoofer, if it's huge enough.
(damn, i already have a set of pivoting transducers and didn't know, only requires to raise the frequency setting
Quantum Stabilizers- Lambert Dinnissen explains rotary yacht stabilizers - YouTube )Maybe a nice subwoofer, if it's huge enough.
(damn, i already have a set of pivoting transducers and didn't know, only requires to raise the frequency setting
Since a simple and thin chord is able to deliver a sound like on a violin or a guitar, why a thin and light diaphragm wouldn't have a similar action ?... The unknow remains the high frequency cut-off of the system : if the actuator isn't correctly dimensioned, the diaphragm will stop its spining at a given frequency, then the system behaves like a low-pass filter !
Since a simple and thin chord is able to deliver a sound like on a violin or a guitar, why a thin and light diaphragm wouldn't have a similar action ?...
Yes that may be the case here - that it delivers a specific tone, with some overtones, but not a full spectrum.
jan
Are you sure of this statement ?... I definitely will give a try before any conclusion...
As sure as you were of your statement
Try is always good, but some things are pretty clear beforehand.
A violin string will never generate a flat full audio spectrum, no matter how hard you try, so if you think that this construction works like a string, good luck!
jan
As sure as you were of your statement
Try is always good, but some things are pretty clear beforehand.
A violin string will never generate a flat full audio spectrum, no matter how hard you try, so if you think that this construction works like a string, good luck!
jan
Precisely, I don't have any statement for the moment regarding this device... Only the required specs of the actuator. You have one instead.
And no Sir, I don't pretend and never wrote that this device works like a string neither. But, I learned long time ago that a vibration of a material will result in the vibration of the surrounding fluid, here the air. Since this diaphragm vibrates at several frequencies, there is a chance you are facing a driver...
What is the usefull frequency range of this device remain simply... unknown from yet! At least for us not for the inventor...
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OK, then I don't know what it is you were meaning with:
"Since a simple and thin chord is able to deliver a sound like on a violin or a guitar, why a thin and light diaphragm wouldn't have a similar action ?... "...
I mean, you seem to be saying that because a string can make a sound like on a violin, therefore a thin and light diaphragm could be a driver ... ? Hmmm. Maybe you meant: "anything that vibrates makes a sound"? I would agree to that.
jan
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Hi,
It not unknown at all and certain aspects are highly predictable.
One thing for sure is it produces no useful bass output whatsover,
and there is no reason to think the rest of the range resembles
hi-fidelity in any shape or form either. There is no theory and
so no real design, jut a load of hot air and not much else.
rgds, sreten.
What do you consider usefull bass? What would the 3db down point be in a typical living room?
I asked Julian Bunn about the bass issue. His response was that yes, it probably could produce bass, but only if you made the 'diaphragm' larger. Hmm..
This is now exactly what I meant... I have to add: if there is a surrounding fluid or material able to propagate this vibration. And again, I just ignore for now the exact frequency range of this device provided I get the adapted actuator to drive efficiently a diaphragm (to be complete, I have also to investigate on this part too...)
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