Hi guys,
I would like to build a homemade speaker from scratch using a 1'' by 1'' neodymium magnet. The voice coil will be wound on a former outside the magnet. Assuming that there will be no pole pieces attached to the magnet, what type of magnet would be suitable to achieve the strongest surface magnetic field? Should it be axially or diametrically magnetized?
It is my understanding that in order to increase magnetic flux/motor strength, the voice coil should be moving perpendicularly to the magnetic field of the permanent magnet. Doesn't this suggest a diametrical magnet?
I would like to build a homemade speaker from scratch using a 1'' by 1'' neodymium magnet. The voice coil will be wound on a former outside the magnet. Assuming that there will be no pole pieces attached to the magnet, what type of magnet would be suitable to achieve the strongest surface magnetic field? Should it be axially or diametrically magnetized?
It is my understanding that in order to increase magnetic flux/motor strength, the voice coil should be moving perpendicularly to the magnetic field of the permanent magnet. Doesn't this suggest a diametrical magnet?
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A) definitely won't work, you'll have the right half of the voice coil pulling "down" when other half pulls "up" and vice versa and there's no way to correct that.
B) is the same, top of VC pulls opposite to what bottom does, but it can be corrected by moving magnet up or down so most or all of it sits outside the VC.
The useful field is that which passes through wire turns perpendicular to VC axis.
Efficiency will be very poor, that's why we use magnetic circuits to drive lines of force where we need them, not all over the place.
B) is the same, top of VC pulls opposite to what bottom does, but it can be corrected by moving magnet up or down so most or all of it sits outside the VC.
The useful field is that which passes through wire turns perpendicular to VC axis.
Efficiency will be very poor, that's why we use magnetic circuits to drive lines of force where we need them, not all over the place.
Hi,
You need axial, to start off with, and pole pieces for a concentrated gap,
which will contain far more flux than any open field arrangements.
Ceramics cannot support the flux levels of pole pieces hence they
they are wide and flat, but Neo's are much more like AlNiCo's
with similar flux capability so you need a similar arrangement.
Look at centre slug AlNiCo speakers, not outside ring.
Its not hard to optimise the gap with basic modelling.
rgds, sreten.
You need axial, to start off with, and pole pieces for a concentrated gap,
which will contain far more flux than any open field arrangements.
Ceramics cannot support the flux levels of pole pieces hence they
they are wide and flat, but Neo's are much more like AlNiCo's
with similar flux capability so you need a similar arrangement.
Look at centre slug AlNiCo speakers, not outside ring.
Its not hard to optimise the gap with basic modelling.
rgds, sreten.
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Hi,
Neo designs tend to be underhung and have thicker polepieces
than ceramic or Alnico. The fact is once you start getting into
the details the idea of a home built driver it makes little sense.
Not that it can't be done, it can, but very hard for it to be
anything than a fairly useless curiosity with no purpose.
rgds, sreten.
Neo designs tend to be underhung and have thicker polepieces
than ceramic or Alnico. The fact is once you start getting into
the details the idea of a home built driver it makes little sense.
Not that it can't be done, it can, but very hard for it to be
anything than a fairly useless curiosity with no purpose.
rgds, sreten.
no, it is possible to get sets of curved magnets that in unity forms a circle
but would be better to machine surface to use ordinary small block magnets
do not ask me where the magnet field is optimal, its just a silly drawing
just a weird one
Hi,
And very poor use of the magnets, or any comprehension of any basic
magnetic principles, file under utterly pointlessly very wrong , not weird.
Its so cluelessly wrong in all respects, appallingly wrong.
Where are you getting such bad designs / ideas from ?
rgds, sreten.
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