Yes I did indeed put in a disclaimer that those were baffle simulations, not DML. I was simply pointing out the issues with comb-filtering in round baffles which may or may not apply to DML's.
@Andre Bellwood
And, here
the midrange are sunk in basins on the front 'baffle', tweeter is jutting out in an inverted horn like tube, long inside the box and the side woofer is also sunk in, but the tube in which it is, juts out. The so-called baffle, thin one in front and the side curvy one are made of such materials, so the so-called edge effects. All the 4 speakers are simply isolated from the 'baffles.' No surface is parralel to each other. That's why I said they have massive R&D departments. I collect somewhat unusual speakers. The shown speakers are placed few cms away from the wall as they have bass-reflex hole on the back. They have a 'sound stage' above the top of them and a bit away behind them and spread to sides. In other words, I don't hear them as coming from the speakers. Other listeners too.
This is quite an interesting pair. You may have noticed that the midrange doesn't appear to have any connection with the voice coil behind them. It is the same with the woofer. If you want, you can watch the dismantling of a newer version.
Looking at the membrane, doesn't it look like a DM membrane, but concave? Or, distributed Balanced Mode membrane? NXT patents also talk about curved membranes as DMLs. 🙂
And, here
the midrange are sunk in basins on the front 'baffle', tweeter is jutting out in an inverted horn like tube, long inside the box and the side woofer is also sunk in, but the tube in which it is, juts out. The so-called baffle, thin one in front and the side curvy one are made of such materials, so the so-called edge effects. All the 4 speakers are simply isolated from the 'baffles.' No surface is parralel to each other. That's why I said they have massive R&D departments. I collect somewhat unusual speakers. The shown speakers are placed few cms away from the wall as they have bass-reflex hole on the back. They have a 'sound stage' above the top of them and a bit away behind them and spread to sides. In other words, I don't hear them as coming from the speakers. Other listeners too.
This is quite an interesting pair. You may have noticed that the midrange doesn't appear to have any connection with the voice coil behind them. It is the same with the woofer. If you want, you can watch the dismantling of a newer version.
Looking at the membrane, doesn't it look like a DM membrane, but concave? Or, distributed Balanced Mode membrane? NXT patents also talk about curved membranes as DMLs. 🙂
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Under suspended? You mean the inverted surround material? If so there are speakers that utilize it. The interesting sound stage is from the drivers being placed on the side of the cabinet, its nothing new.
Kef's Blade speakers has side firing drivers.
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Hi TNT, (@TNT)
I must admit I'm not sure if you are agreeing or disagreeing! I can't be sure if you read my whole (long, sorry) post or not.
For sure I agree that with respect to a DML panel, it is the speed of the panel's bending waves that matter, as it is the bending waves in the plate (and not longitudinal waves) that generates the sound waves in the air.
But my point was that when most people talk about the "speed of sound" in a solid material, they are talking about the speed of longitudinal waves, not bending waves. But the two are quite different things.
Longitudinal wave speed is given by this equation:
While bending wave speed is given by this:
The one similarity is the dependance on E and rho. But the speed of longitudinal waves is simply a constant depending on the material properties, while the bending wave speed is a function of frequency and of the thickness of the plate.
But many people don't realize the two are (very) different things.
Eric
So would that be analogous to wave speed underwater vs wave speeds on the surface?
Further to post #8,655
Even though the exact words were not mentioned, BMR was invented by NXT, patent WO 2005/101899.
Interestingly, in that patent, NXT moved somewhat away from the asymmetric placing of one transducer on a flat rectangular panel, to symmetric placing of few transducers in regard of the centre of mass of the panel, vertically or diagonally, such as,
And, this one,
and this, 
confirms my thinking of using a conventional cone speaker with a thin quite stiff cone on the back of a thin under suspended membrane, whether circular or rectangular that membrane is.
Now, thinking about the LG's concave shallow speaker drivers (#8,683, #8,684), I might try to find another pair to dismantle them to get those drivers out to use them behind panels, maybe filled with some foam as Hitachi did once. 🙂
Even though the exact words were not mentioned, BMR was invented by NXT, patent WO 2005/101899.
Interestingly, in that patent, NXT moved somewhat away from the asymmetric placing of one transducer on a flat rectangular panel, to symmetric placing of few transducers in regard of the centre of mass of the panel, vertically or diagonally, such as,
And, this one,
and this, confirms my thinking of using a conventional cone speaker with a thin quite stiff cone on the back of a thin under suspended membrane, whether circular or rectangular that membrane is.
Now, thinking about the LG's concave shallow speaker drivers (#8,683, #8,684), I might try to find another pair to dismantle them to get those drivers out to use them behind panels, maybe filled with some foam as Hitachi did once. 🙂
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Take my advice or leave it I dont care what you do. You jump from one design to another DAILY, without doing anything at all. All talk no walk.
Further to post #8,691,
This,
gives credence to @Eucyblues99 Eucydome and what @spedge had been doing adding weights to stop distrotion in his panels.
This,
gives credence to @Eucyblues99 Eucydome and what @spedge had been doing adding weights to stop distrotion in his panels.
Be gentle
"True enthusiasm is a fine feeling whose flash I admire where-ever I see it."
Charlotte Bronte
😁👍
Eucy
Glad to hear you sorted out your stereo problems.
STEVE.
I am all for enthusiasm, but when one does nothing and does not accomplish anything time after time the enthusiasm turns into annoyance. If he is as smart as he thinks he is he should be able to build a better sounding DML panel then everyone here.
You got good ears and the sharpest tool in this shed. 🙂
This is a very interesting find! The cheaper ones with the thinner aluminium facings look like very good value. I do wonder how they would compare with my 2mm ceiba plywood panels though. £9.95 delivery charge for <£150 orders.
I will be rehousing my 15" Monacor PA drivers in H frames when the weather gets better (i.e. I can get the panels cut at B&Q and into the car without being rained/snowed on). I will then be in the market to replace my current 30x40cm ceiba panels with something a bit larger. My previous 55x40 poplar panels seemed to have better midrange detail, so 55x40 ceiba seems like a possibility.
With active crossovers & EQ, my current hybrid setup is +/-1.5db from 35hz to 18khz with a drop off above that. Whilst the overall tonality is fine, things seem to get a bit confused with complex orchestral passages. it is, however, very revealing of recording quality (and lack thereof).