Hi Chris,

Sorry; I do see MY lateral text description error.  The 2 ring mags are
common in that they are polarized
through the thickness, not the ring outer diameter, with the usual Internal
Diameter hole.  Each N - S represents
the poles of a single magnet, and they (the letters) are of course much
wider than the thickness.  The center
mag holes would be vertical per this view and are not seen.  They are not
diametrically magnetized (sideways
through the outer ring diameter....hmmmm....which might be also
interesting....ha.  Of course any coil/s would
drop down the center of this "stack".  Below is a stack of 2 ring magnets:

N
-
S
N
-
S

What Brett proposed is:

N
-
S
S
-
N

What might be mechanically more practical is to insert a non-magnetic
spacer, shown below with the letter "O".

N
-
S
O
S
-
N
Wish I had some large ring neo mags on hand to try it out and whomp up a
simple web photo page; but alas;
no; for the moment.  Of course its hard to match common round coils with the
internal diameter of ring magnets
to where their is some space for movement versus....too much space (too
small a coil for the mag ID).  They
might be interesting to check out...but...one can't adjust much here.

Of course, just using 4 square/rectangular neo's within 2 plates of iron
metal, gives quite excellent sensitivity with
using round coils.  Indeed; for dampening curiosity, I tried such recently,
and with the coil leads shorted, it had
quite a very pronounced eddy current drag, I've never seen before with other
magnet arrangements for the specific
2k resistance coil I used as a test coil.

Take care, Meredith

On Mon, Jun 2, 2008 at 5:52 PM,  wrote:

> In a message dated 2008/06/02, paleoartifact@......... writes:
>
> Hmmm, here is a new/old speaker/voice coil speculation idea, which I don't
> think has been covered before in PSN email.
>
>
>
> Hi Meredith,
>
>        I can't follow the construction proposed from your description. Can
> you make a sketch, please?
>        Are the ring Neo magnets magnetised along their length?
>
>        Regards,
>
>        Chris
Hi Chris,
 
Sorry; I do see MY lateral text description error.  The 2 ring mags are common in that they are polarized
through the thickness, not the ring outer diameter, with the usual Internal Diameter hole.  Each N - S represents
the poles of a single magnet, and they (the letters) are of course much wider than the thickness.  The center
mag holes would be vertical per this view and are not seen.  They are not diametrically magnetized (sideways
through the outer ring diameter....hmmmm....which might be also interesting....ha.  Of course any coil/s would
drop down the center of this "stack".  Below is a stack of 2 ring magnets:
 
N
-
S
N
-
S
 
What Brett proposed is:
 
N
-
S  
S
-
N
 
What might be mechanically more practical is to insert a non-magnetic spacer, shown below with the letter "O".
 
N
-
S
O
S
-
N

Wish I had some large ring neo mags on hand to try it out and whomp up a simple web photo page; but alas;
no; for the moment.  Of course its hard to match common round coils with the internal diameter of ring magnets
to where their is some space for movement versus....too much space (too small a coil for the mag ID).  They
might be interesting to check out...but...one can't adjust much here.
 
Of course, just using 4 square/rectangular neo's within 2 plates of iron metal, gives quite excellent sensitivity with
using round coils.  Indeed; for dampening curiosity, I tried such recently, and with the coil leads shorted, it had
quite a very pronounced eddy current drag, I've never seen before with other magnet arrangements for the specific
2k resistance coil I used as a test coil.
 
Take care, Meredith  
 
On Mon, Jun 2, 2008 at 5:52 PM, <ChrisAtUpw@.......> wrote:


In a message dated 2008/06/02, paleoartifact@......... writes:


Hmmm, here is a new/old speaker/voice coil speculation idea, which I don't think has been covered before in PSN email.


Hi Meredith,

       I can't follow the construction proposed from your description. Can you make a sketch, please?
       Are the ring Neo magnets magnetised along their length?

       Regards,


       Chris