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is this "inverter" stuff a big deal? (see link)

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Anonymous
June 3, 2005 2:02:14 AM

Archived from groups: rec.audio.pro (More info?)

http://www.finalsound.com/design.html

opinions, Bueller, anyone? :-)

2004 seems pretty current for a "breakthough" patent in electrostatic
designs.

wondering if this company is making "Quad killers" either in overall
quality or in price vs. quality.
Anonymous
June 3, 2005 5:27:47 AM

Archived from groups: rec.audio.pro (More info?)

genericaudioperson@hotmail.com wrote:
> http://www.finalsound.com/design.html
>
> opinions, Bueller, anyone? :-)
>
> 2004 seems pretty current for a "breakthough" patent in electrostatic
> designs.
>
> wondering if this company is making "Quad killers" either in overall
> quality or in price vs. quality.

Insufficient information at the site to draw any
conclusions. Beyond saying that they "embed the signal
inside a sealed diaphragm" they give no information about
the technology. Technobabble.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein
Anonymous
June 3, 2005 9:24:15 AM

Archived from groups: rec.audio.pro (More info?)

On 2 Jun 2005 22:02:14 -0700, genericaudioperson@hotmail.com wrote:

>http://www.finalsound.com/design.html

>2004 seems pretty current for a "breakthough" patent in electrostatic
>designs.
>
>wondering if this company is making "Quad killers" either in overall
>quality or in price vs. quality.

Electrostatic speakers were being made before there were practical
permanent magnets of speaker size. Newness is questionable; ad copy
is bogus; not a deal-killer, but...

But, hey, most ad copy is offensive. If it's terrible, boycott; if
it's livable, hold your nose. And, yeah, this looks icky.

Good fortune,

Chris Hornbeck
Anonymous
June 3, 2005 9:26:23 AM

Archived from groups: rec.audio.pro (More info?)

Bob Cain wrote:
> genericaudioperson@hotmail.com wrote:
>> http://www.finalsound.com/design.html
>>
>> opinions, Bueller, anyone? :-)
>>
>> 2004 seems pretty current for a "breakthough" patent in
electrostatic
>> designs.
>>
>> wondering if this company is making "Quad killers" either
in overall
>> quality or in price vs. quality.
>
> Insufficient information at the site to draw any
> conclusions. Beyond saying that they "embed the signal
> inside a sealed diaphragm" they give no information about
> the technology. Technobabble.

I get the feeling that they are insulating the charged
surface from the environment by laminating it between two
sheets of plastic. The major challenge is doing that
without thickening the diaphragm to the point where it
becomes too acoustically non-ideal. However, if they do
that, they still end up with an electrostatic loudspeaker
with all the rest of the other problems with electrostatic
speakers.

I seem to recall, some years ago seeing similar prototype
electrostatic flat panel drivers that were made by the same
now-defunct Vancouver company that made those Monsoon
computer speakers that were based on electrodynamic flat
panel drivers. I don't recall too much about them except
that people who compared the electrodynamic version of the
drivers to the electrostatic version quickly settled on the
electrodynamic version.
Anonymous
June 3, 2005 9:51:07 PM

Archived from groups: rec.audio.pro (More info?)

<genericaudioperson@hotmail.com>

> http://www.finalsound.com/design.html
>
>
> 2004 seems pretty current for a "breakthough" patent in electrostatic
> designs.
>


** What dam patent - an application only is mentioned.


> wondering if this company is making "Quad killers" either in overall
> quality or in price vs. quality.


** The blurb reeks of snake oil bullshit from beginning to end.

A pic (or CGI ?? ) shows small ES panels mounted flat against a wall !!!!

The PDF that hopefully explained all would not download - while the PDFs
that explained nothing downloaded fine.


What do you learn from this ???





............. Phil
Anonymous
June 3, 2005 11:54:06 PM

Archived from groups: rec.audio.pro (More info?)

"Arny Krueger"

>
> I get the feeling that they are insulating the charged
> surface from the environment by laminating it between two
> sheets of plastic.


** Reading between the babble - the "inversion" is to drive the diaphragm
(as opposed to the stator panels) with the audio signal. This eliminates
the need for antiphase drive signals - hence the (dubious) lower drive
power claim.

This also means the diaphragm must be a highly conductive surface so the
audio frequency voltage will spread across the surface instantly - so a
metallised polyester film is likely, with a plain film layer on top. The
same stuff millions of caps are made from possibly.

Conventional ( since early 1950s) ESLs are NOT made this way as it allows
charge migration on the conducting surface and uneven drive forces across
the diaphragm - leading to the generation of harmonics.




.............. Phil
Anonymous
June 3, 2005 11:54:07 PM

Archived from groups: rec.audio.pro (More info?)

Phil Allison wrote:

> This also means the diaphragm must be a highly conductive surface so the
> audio frequency voltage will spread across the surface instantly - so a
> metallised polyester film is likely, with a plain film layer on top. The
> same stuff millions of caps are made from possibly.
>
> Conventional ( since early 1950s) ESLs are NOT made this way as it allows
> charge migration on the conducting surface and uneven drive forces across
> the diaphragm - leading to the generation of harmonics.

Since that time push-pull ESL devices have always utilized
_high_ resistance coating on the diaphragm to trap the
charge and prevent migration. The signal is applied across
the stators, one on each side, and the trapped charge on the
diaphragm between them receives the bidirectional motive force.

What configuration could apply signal to the diaphragm and
give bi-directional motive force? How could trapped charge
be used to prevent distortion?

I think they are blowing smoke.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein
Anonymous
June 4, 2005 3:21:22 AM

Archived from groups: rec.audio.pro (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:3gagfbFbcc8iU1@individual.net...
>
> <genericaudioperson@hotmail.com>
>
>> http://www.finalsound.com/design.html
>>
>>
>> 2004 seems pretty current for a "breakthough" patent in electrostatic
>> designs.
>>
>
>
> ** What dam patent - an application only is mentioned.
>
>
>> wondering if this company is making "Quad killers" either in overall
>> quality or in price vs. quality.
>
>
> ** The blurb reeks of snake oil bullshit from beginning to end.
>
> A pic (or CGI ?? ) shows small ES panels mounted flat against a wall !!!!
>
> The PDF that hopefully explained all would not download - while the PDFs
> that explained nothing downloaded fine.
>
>
> What do you learn from this ???

Quad Boi is a dumb ass?


>
>
>
>
>
> ............ Phil
>
>
>
>
>
Anonymous
June 4, 2005 5:06:21 AM

Archived from groups: rec.audio.pro (More info?)

On Fri, 03 Jun 2005 17:01:23 -0700, Bob Cain
<arcane@arcanemethods.com> wrote:

>Phil Allison wrote:

>> Conventional ( since early 1950s) ESLs are NOT made this way as it allows
>> charge migration on the conducting surface and uneven drive forces across
>> the diaphragm - leading to the generation of harmonics.
>
>Since that time push-pull ESL devices have always utilized
>_high_ resistance coating on the diaphragm to trap the
>charge and prevent migration. The signal is applied across
>the stators, one on each side, and the trapped charge on the
>diaphragm between them receives the bidirectional motive force.
>
>What configuration could apply signal to the diaphragm and
>give bi-directional motive force? How could trapped charge
>be used to prevent distortion?

The constant charge diaphragm also changes the voltage-vs-
excursion from square law to linear. This might be pretty tough
to work around.

Chris Hornbeck
Anonymous
June 4, 2005 5:22:56 PM

Archived from groups: rec.audio.pro (More info?)

"Bob Cain"
> Phil Allison wrote:
>
>> This also means the diaphragm must be a highly conductive surface so the
>> audio frequency voltage will spread across the surface instantly - so a
>> metallised polyester film is likely, with a plain film layer on top. The
>> same stuff millions of caps are made from possibly.
>>
>> Conventional ( since early 1950s) ESLs are NOT made this way as it
>> allows charge migration on the conducting surface and uneven drive forces
>> across the diaphragm - leading to the generation of harmonics.
>
> Since that time push-pull ESL devices have always utilized _high_
> resistance coating on the diaphragm to trap the charge and prevent
> migration. The signal is applied across the stators, one on each side,
> and the trapped charge on the diaphragm between them receives the
> bidirectional motive force.
>
> What configuration could apply signal to the diaphragm and give
> bi-directional motive force?


** The reciprocal one does - where the stators are held at equal and
opposite voltages and the diaphragm has a varying state of charge and
polarity.


> How could trapped charge be used to prevent distortion?


** What if the metallised coating on the diaphragm were applied in a
continuous spiral pattern ??

Might prevent charge migration ACROSS the surface.


> I think they are blowing smoke.


** Blowing something smelly at least.



............. Phil
Anonymous
June 4, 2005 5:22:57 PM

Archived from groups: rec.audio.pro (More info?)

On Sat, 4 Jun 2005 13:22:56 +1000, "Phil Allison"
<philallison@tpg.com.au> wrote:

>"Bob Cain"

>> What configuration could apply signal to the diaphragm and give
>> bi-directional motive force?

>** The reciprocal one does - where the stators are held at equal and
>opposite voltages and the diaphragm has a varying state of charge and
>polarity.

Yeah, but only assuming the linearity of the constant-charge
transfer characteristics. Otherwise the diaphragm would
simply migrate towards the randomly stronger charge.

Maybe the original thought was complete; dunno, but I've
seen it a lot. Some of these guys like P J Baxandall,
P J Walker, D T N Williamson, Blumlein, etc. have just
gotten so old that they're dead. Don't mean that they're
wrong.

>> I think they are blowing smoke.
>
>
> ** Blowing something smelly at least.

Happens.

Chris Hornbeck
"He thought so little they rewarded he,
By making him the ruler of the Queen's Navy".
Anonymous
June 4, 2005 5:22:57 PM

Archived from groups: rec.audio.pro (More info?)

Phil Allison wrote:

>>What configuration could apply signal to the diaphragm and give
>>bi-directional motive force?
>
>
>
> ** The reciprocal one does - where the stators are held at equal and
> opposite voltages and the diaphragm has a varying state of charge and
> polarity.

Can you try to draw that in ascii (crude is fine)? I can't
picture it or how it would be driven with a signal.

>>How could trapped charge be used to prevent distortion?
>
> ** What if the metallised coating on the diaphragm were applied in a
> continuous spiral pattern ??
>
> Might prevent charge migration ACROSS the surface.

Nah, light's too speedy unless there is an R in series with
a C. R has to be big in this case so that the time constant
is signifigantly less than the lowest frequency to be
reproduced.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein
Anonymous
June 4, 2005 5:22:58 PM

Archived from groups: rec.audio.pro (More info?)

Chris Hornbeck wrote:

> Some of these guys like...... Blumlein, etc. have just gotten so old that
> they're dead.

Well, Alan Blumlein died in an aircraft accident over Wales IIRC testing the
H2S terrain mapping radar circa 1942 or thereabouts. Not old at all.

Cheers, Graham
Anonymous
June 5, 2005 4:21:17 PM

Archived from groups: rec.audio.pro (More info?)

"Bob Cain"
> Phil Allison wrote:
>
>>>What configuration could apply signal to the diaphragm and give
>>>bi-directional motive force?
>>
>>
>>
>> ** The reciprocal one does - where the stators are held at equal and
>> opposite voltages and the diaphragm has a varying state of charge and
>> polarity.
>
> Can you try to draw that in ascii (crude is fine)? I can't picture it or
> how it would be driven with a signal.



** --------------------------------- +2KV rel to 0v.

___________________________ boosted audio rel to 0v.


---------------------------------- - 2KV rel to 0v




>>>How could trapped charge be used to prevent distortion?
>>
>> ** What if the metallised coating on the diaphragm were applied in a
>> continuous spiral pattern ??
>>
>> Might prevent charge migration ACROSS the surface.
>
> Nah,


** Just a top of the head thought.




............. Phil
Anonymous
June 8, 2005 3:33:24 AM

Archived from groups: rec.audio.pro (More info?)

Bob Cain <arcane@arcanemethods.com> wrote in
news:D 7qr0g02e9e@enews4.newsguy.com:


> I think they are blowing smoke.
> Bob


In light of the smoke that you blow on a regular basis, you certainly ought
to know.
Anonymous
June 9, 2005 12:18:53 AM

Archived from groups: rec.audio.pro (More info?)

Phil Allison wrote:
> "Bob Cain"
>
>>Phil Allison wrote:
>>
>>
>>>>What configuration could apply signal to the diaphragm and give
>>>>bi-directional motive force?
>>>
>>>
>>>
>>>** The reciprocal one does - where the stators are held at equal and
>>>opposite voltages and the diaphragm has a varying state of charge and
>>>polarity.
>>
>>Can you try to draw that in ascii (crude is fine)? I can't picture it or
>>how it would be driven with a signal.
>
>
>
>
> ** --------------------------------- +2KV rel to 0v.
>
> ___________________________ boosted audio rel to 0v.
>
>
> ---------------------------------- - 2KV rel to 0v
>

Had to think about this just a bit. Yes, it should work
fine. With the usual configuration you have a dynamic
electric field working on a static charge and with this
inversion you have a static electric field working on a
dynamic charge.

I haven't worked through the electrostatics, however, to
make sure the electroacoustic coupling is the same but it
seems like it should be at first blush.

You can solve the charge mobility problem in a fashion
similar to the usual configuration, use a high resistance
coating on an insulator as stators.

I don't see any advantage, though. It requires two bias
supplies instead of one and a metalized diaphragm. Having
stators made of an insulating material seems to be less
desirable than metal from a durability standpoint.


Thanks,

Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein
Anonymous
June 9, 2005 7:52:06 AM

Archived from groups: rec.audio.pro (More info?)

On Wed, 08 Jun 2005 20:18:53 -0700, Bob Cain
<arcane@arcanemethods.com> wrote:

>You can solve the charge mobility problem in a fashion
>similar to the usual configuration, use a high resistance
>coating on an insulator as stators.

Does this make the tranfer curve linear rather than square
law? Too late here and I'm not smart enough to be very
definitive...

At (very) first blush, I'd say no, but eagerly awaiting
your comments.

Chris Hornbeck
"For a change, she got out,
'Fore he hurt her bad.
Took her records and clothes,
And pictures of her boy." -Elliott Smith
Anonymous
June 9, 2005 7:52:07 AM

Archived from groups: rec.audio.pro (More info?)

Chris Hornbeck wrote:
> On Wed, 08 Jun 2005 20:18:53 -0700, Bob Cain
> <arcane@arcanemethods.com> wrote:
>
>
>>You can solve the charge mobility problem in a fashion
>>similar to the usual configuration, use a high resistance
>>coating on an insulator as stators.
>
>
> Does this make the tranfer curve linear rather than square
> law? Too late here and I'm not smart enough to be very
> definitive...
>
> At (very) first blush, I'd say no, but eagerly awaiting
> your comments.

I knew that as soon as I responded I'd have second thoughts.
Always works that way. For there to be a capacitor to
hold the opposite charge from what's on the diaphragm, the
stators must be conductive so we can forget about mitigating
charge migration by making them a high resistance. Any
diaphragm curvature will have a pronounced effect.

Now, in addition to the field created by the opposing DC
charge on the stators there is a field between the (signal
charged) diaphragm and each stator as well and the fields on
each side are different when the diaphragm is offset. Thus
we don't just have a dynamic charge in a static field as I
first thought and it could well be that the field assymetry
that is a function of position leaves the non-linearity as
you suspect. Something similar happens, however, with the
standard configuration so I'm not sure yet.

It isn't clear to me right now how this all works out in the
end. Need to find more time to analyze it in detail.
Please, someone, beat me to it. :-)


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein
!