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Planar Magnetic

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There's nothing new about them, they've been around for years. They're supposed to very high fidelity for mid/upper range frequencies, their low frequency reproduction is horrible though unless their size is exceptionally large, so they're more often seen accompanying a dynamic woofer, at least for full range coverage.
 
There's nothing new about them, they've been around for years. They're supposed to very high fidelity for mid/upper range frequencies, their low frequency reproduction is horrible though unless their size is exceptionally large, so they're more often seen accompanying a dynamic woofer, at least for full range coverage.

Thanks Sceadwian for your reply,

But if there is nothing new about them, Plaese tell me how these focuced audio "MAD" devices do work regarding this teconlogy?!:
https://www.google.com/#sclient=psy...gc.r_pw.&fp=4f5d99df8e6c9a1d&biw=1440&bih=728
 
They're nothing more than massively scaled up versions of the speakers you're talking about. The reason they're useful as a crowd control is because they're output is dipole in nature, which means especially with a well designed phased array you can aim the acoustical beam itself to a VERY small area, effecting only a tiny portion of a group. The psycho acoustics themselves are beyond the scope of planar magnetics. Basically they just produce REALLY loud directional sounds signals that are so loud and distracting they override conscious action.

It's still a slightly controversial technology because up close it can kill or permanently deafen anyone it's aimed at and even at a distance there is a very fine line between an effective deterrent and permanently damaging the hearing of the target.
 
They're nothing more than massively scaled up versions of the speakers you're talking about. The reason they're useful as a crowd control is because they're output is dipole in nature, which means especially with a well designed phased array you can aim the acoustical beam itself to a VERY small area, effecting only a tiny portion of a group. The psycho acoustics themselves are beyond the scope of planar magnetics. Basically they just produce REALLY loud directional sounds signals that are so loud and distracting they override conscious action.

It's still a slightly controversial technology because up close it can kill or permanently deafen anyone it's aimed at and even at a distance there is a very fine line between an effective deterrent and permanently damaging the hearing of the target.

looks nice analysis.
 
They're nothing more than massively scaled up versions of the speakers you're talking about. The reason they're useful as a crowd control is because they're output is dipole in nature, which means especially with a well designed phased array you can aim the acoustical beam itself to a VERY small area, effecting only a tiny portion of a group. The psycho acoustics themselves are beyond the scope of planar magnetics. Basically they just produce REALLY loud directional sounds signals that are so loud and distracting they override conscious action.

It's still a slightly controversial technology because up close it can kill or permanently deafen anyone it's aimed at and even at a distance there is a very fine line between an effective deterrent and permanently damaging the hearing of the target.

OK thanks.
First I have to say that I am not sure if a Phased array is the right thing for sound focusing because of huygens principle limitation:
https://en.wikipedia.org/wiki/Huygens–Fresnel_principle

Bisedes they seem not to use any pased array for their MAD devices.
I am not sure how directional the device is itself.

Sorry but what do you mean by this:

""and even at a distance there is a very fine line between an effective deterrent and permanently damaging the hearing of the target. ""
 
Ok, actually I decided to make a planar or a line source to see how directional it could be, and if it obeys "huygens principle" by incrasing the audio opening or the audio sources?
I will let you know the results.
 
Many concert sound systems use a phased array of speakers to make them very directional which concentrates their sound to be much louder.

Years ago Yamaha invented and sold a way to produce bass from a small woofer by using positive feedback. It didn't work but they sold many of them anyway.

Many years ago I bought a Yamaha stereo receiver that still works perfectly (except for a switch that is intermittent because it has silver contacts instead of gold contacts that cost the same).
 
Many concert sound systems use a phased array of speakers to make them very directional which concentrates their sound to be much louder.

Years ago Yamaha invented and sold a way to produce bass from a small woofer by using positive feedback. It didn't work but they sold many of them anyway.

Many years ago I bought a Yamaha stereo receiver that still works perfectly (except for a switch that is intermittent because it has silver contacts instead of gold contacts that cost the same).

Well, Yea, but I meant no phased array is able to focus sound and KEEP it in a such manner. Make sense? So focusing sound for a MAD device is not so useful because (and even if it happened to use phased arrays) the focused sound will be spread out soon due to huygens principle.
 
The frequency the modern MAD arrays actually uses are far above audible, it's the constructive/destructive array that focuses them to the audible spectrum, far more directional than a simple planar magnetic array, the human acoustical arrays (speakers) simply use matrices along the same theme, but with less complexity, a single planar magnetic speaker behaves as I said as a dipole. 3db in front, decreased to null at a side lobe, and 3db behind as far as power goes.

Goes a long way to describe it.

and even at a distance there is a very fine line between an effective deterrent and permanently damaging the hearing of the target.
Work out the math.
 
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Transmitting and receiving antennas also use an array to gain directionality and sensitivity.
 

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What the heck kind of speaker array is that audioguru?
 
What the heck kind of speaker array is that audioguru?
I found it in Google Images. It has a bunch of woofers and electrostatic tweeters in a vertical array so it beams a narrow horizontal beam of sound that does not bounce off the floor and ceiling and it concetrates the sound making it louder if you are in the beam.
 
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